iOS Browsers

(default settings)
brave logo
brave
1.64
chrome logo
chrome
124.6367
duckduckgo logo
duckduckgo
7.116
edge logo
edge
124.2478
firefox logo
firefox
125.2
focus logo
focus
125.0
opera logo
opera
4.6
safari logo
safari
17.4
vivaldi logo
vivaldi
6.3287
yandex logo
yandex
2404.3
State Partitioning testsWhich browsers isolate websites to prevent them from sharing data to track you?
A common vulnerability of web browsers is that they allow tracking companies to 'tag' your browser with some data ('state') that identifies you. When third-party trackers are embedded in websites, they can see this identifying data as you browse to different websites. Fortunately, it is possible for this category of leaks to be fixed by partitioning all data stored in the browser such that no data can be shared between websites.
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
blob
A 'blob URL' is a local reference to some raw data. Trackers can use a blob URL to share data between websites.
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
BroadcastChannel
A BroadcastChannel is designed to send messages between tabs. In some browsers it can be used for cross-site communication and tracking.
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })
result, same first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
ab578407-370d-4f49-b646-146a5387984b,
1a009336-8fc6-4c29-9156-8b7703d81ecb,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
aaafbb05-7196-4933-bb52-b72db6df608a,
d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1,
a7f946cf-faa8-4c53-becc-c6519f6bba4f,
ee2fce28-59db-4014-a550-5b43f289183d,
f882e270-5804-4f67-be63-599dba30cc12,
8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
c846cb44-12d2-41b3-b2a6-38ca1a4518ed,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9,
81902166-5563-4879-b345-eb7a086625ea,
8f539dfe-0634-42b6-8409-acef00b99289,
679ab034-ba16-4437-935c-e64f06433be9,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff,
6d3e0086-b2ae-468d-b231-683355928a4d,
28ad0d17-5e84-40ee-af86-a5c9175e415d,
1c564983-4c6a-4bea-be2a-dcccb8295bef,
638188b4-c2fc-4133-8b65-797114180f04
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36,
9194ae03-b335-40f3-af6f-718e7be9c8ae,
f1c5e294-1695-4474-9704-2d549880ce28,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
c8baedb9-0082-4eec-9aca-059c23d731c5,
73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159,
fdbdfe87-3692-40b7-bc31-76b969b98541,
f84e10ce-2813-440f-bda8-0a17d63d0c90,
c602aba9-2920-4010-a515-bd9d1c8539d8,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
52d604c6-2ce9-4838-934f-3e90c4bcda12,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
76391515-fb72-4c62-a581-0a8c545f276b
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
ab578407-370d-4f49-b646-146a5387984b_http,
1a009336-8fc6-4c29-9156-8b7703d81ecb_http,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_http,
aaafbb05-7196-4933-bb52-b72db6df608a_http,
d0134525-2c97-46f5-a372-2e6c225c3019_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1_http,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_http,
ee2fce28-59db-4014-a550-5b43f289183d_http,
f882e270-5804-4f67-be63-599dba30cc12_http,
8bb057b5-ccc8-478a-8d42-5651ab499e89_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627_http,
528a685d-63c8-4a8c-88ec-037d368af791_http,
30d559cc-0031-4a5b-a870-4f11b6a100a0_http,
b2c792f8-1b1a-493f-8388-fe17cfc99931_http,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9_http,
81902166-5563-4879-b345-eb7a086625ea_http,
8f539dfe-0634-42b6-8409-acef00b99289_http,
679ab034-ba16-4437-935c-e64f06433be9_http,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff_http,
6d3e0086-b2ae-468d-b231-683355928a4d_http,
28ad0d17-5e84-40ee-af86-a5c9175e415d_http,
1c564983-4c6a-4bea-be2a-dcccb8295bef_http,
638188b4-c2fc-4133-8b65-797114180f04_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_http,
ffeb2f66-c77b-474f-a305-a04f4afc87af_http,
b2954dd3-3942-497b-9059-edc1f51db921_http,
294cc579-3da1-4084-9f1f-59c61c553cf9_http,
02e3522b-e907-4849-98dd-593d197989e0_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36_http,
9194ae03-b335-40f3-af6f-718e7be9c8ae_http,
f1c5e294-1695-4474-9704-2d549880ce28_http,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_http,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af_http,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_http,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_http,
c8baedb9-0082-4eec-9aca-059c23d731c5_http,
73afc3df-3d35-4c5c-8056-96142486ae81_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159_http,
fdbdfe87-3692-40b7-bc31-76b969b98541_http,
f84e10ce-2813-440f-bda8-0a17d63d0c90_http,
c602aba9-2920-4010-a515-bd9d1c8539d8_http,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b_http,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_http,
52d604c6-2ce9-4838-934f-3e90c4bcda12_http,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_http,
76391515-fb72-4c62-a581-0a8c545f276b_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
ab578407-370d-4f49-b646-146a5387984b_js,
1a009336-8fc6-4c29-9156-8b7703d81ecb_js,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_js,
aaafbb05-7196-4933-bb52-b72db6df608a_js,
d0134525-2c97-46f5-a372-2e6c225c3019_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1_js,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_js,
ee2fce28-59db-4014-a550-5b43f289183d_js,
f882e270-5804-4f67-be63-599dba30cc12_js,
8bb057b5-ccc8-478a-8d42-5651ab499e89_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627_js,
528a685d-63c8-4a8c-88ec-037d368af791_js,
30d559cc-0031-4a5b-a870-4f11b6a100a0_js,
b2c792f8-1b1a-493f-8388-fe17cfc99931_js,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9_js,
81902166-5563-4879-b345-eb7a086625ea_js,
8f539dfe-0634-42b6-8409-acef00b99289_js,
679ab034-ba16-4437-935c-e64f06433be9_js,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff_js,
6d3e0086-b2ae-468d-b231-683355928a4d_js,
28ad0d17-5e84-40ee-af86-a5c9175e415d_js,
1c564983-4c6a-4bea-be2a-dcccb8295bef_js,
638188b4-c2fc-4133-8b65-797114180f04_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_js,
ffeb2f66-c77b-474f-a305-a04f4afc87af_js,
b2954dd3-3942-497b-9059-edc1f51db921_js,
294cc579-3da1-4084-9f1f-59c61c553cf9_js,
02e3522b-e907-4849-98dd-593d197989e0_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36_js,
9194ae03-b335-40f3-af6f-718e7be9c8ae_js,
f1c5e294-1695-4474-9704-2d549880ce28_js,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_js,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af_js,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_js,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_js,
c8baedb9-0082-4eec-9aca-059c23d731c5_js,
73afc3df-3d35-4c5c-8056-96142486ae81_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159_js,
fdbdfe87-3692-40b7-bc31-76b969b98541_js,
f84e10ce-2813-440f-bda8-0a17d63d0c90_js,
c602aba9-2920-4010-a515-bd9d1c8539d8_js,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b_js,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_js,
52d604c6-2ce9-4838-934f-3e90c4bcda12_js,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_js,
76391515-fb72-4c62-a581-0a8c545f276b_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_1848542379774103,
fake_7398072826743334,
fake_06392173246936816,
fake_07771287326284781,
fake_6721438418644574
result, different first party:
fake_736453250728863,
fake_9704474979766653,
fake_707329639671437,
fake_3200860435174271,
fake_937987710202524
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_27665288587912773,
fake_02059469346552234,
fake_01889809061892045,
fake_8140825921556132,
fake_31714671228183233
result, different first party:
fake_3849396275560435,
fake_4520929023854392,
fake_17794429395290456,
fake_5121198502169451,
fake_46762925656211163
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_1898534355513677,
fake_07970978685769925,
fake_34786423059160954,
fake_7266259549614043,
fake_4544479978826952
result, different first party:
fake_5671638220092201,
fake_15695590198371967,
fake_7460172047964446,
fake_5690346344887207,
fake_4358211815349322
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_7541703367328865,
fake_15972928864288294,
fake_7502125085379359,
fake_021499525167693045,
fake_4685723002433584
result, different first party:
fake_16064838337638299,
fake_41970144185508373,
fake_5160500607645977,
fake_9349758573555382,
fake_08726835325167182
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_4658309934897229,
fake_10047834252457766,
fake_8153862115947261,
fake_40424992284164274,
fake_4090717620922155
result, different first party:
fake_9895745305696886,
fake_18927174914573963,
fake_9425741088526536,
fake_8928556068231122,
fake_10272208452352127
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_1496749168515028,
fake_7967961955678713,
fake_40711849100395314,
fake_6869232966916097,
fake_0183371827387242
result, different first party:
fake_748520847204001,
fake_8305335033569683,
fake_3095404431030446,
fake_3842787673529129,
fake_08825406509754008
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_49924241778418144,
fake_47953622216012204,
fake_6929838334377174,
fake_11462918745309403,
fake_8029721546353565
result, different first party:
fake_2962435675190265,
fake_7543757389439103,
fake_26095787119048564,
fake_10557213722876302,
fake_3469993685874633
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_2765366187102658,
fake_7514415245265396,
fake_03163360231045376,
fake_7636295448845725,
fake_5306016402053304
result, different first party:
fake_8556768644484816,
fake_958641906064188,
fake_9325032045781196,
fake_7013643952960076,
fake_12528511984176882
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_09445011855553331,
fake_4906325710039394,
fake_7556188269556683,
fake_3728371028869877,
fake_1904428224512582
result, different first party:
fake_26217338557069914,
fake_39307713981213577,
fake_384675651939685,
fake_5822495813874289,
fake_5938976957748454
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_6525803124657266,
fake_788081692078022,
fake_13019819886825323,
fake_8761958195518573,
fake_9115700768023305
result, different first party:
fake_43450828413890497,
fake_9335859248711977,
fake_04562849806702962,
fake_776479775647448,
fake_4393521851407658
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 2, 2, 2
result, different first party: 1, 1, 2, 2, 2
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
getDirectory
navigator.storage.getDirectory exposes a location for storing files to web content. In some cases, these files may be shared across tabs.
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party: , , , ,
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
H1 connection
HTTP/1.x are the classic web connection protocols. If these connections are re-used across websites, they can be used to track users.
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
ab578407-370d-4f49-b646-146a5387984b,
1a009336-8fc6-4c29-9156-8b7703d81ecb,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
aaafbb05-7196-4933-bb52-b72db6df608a,
d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1,
a7f946cf-faa8-4c53-becc-c6519f6bba4f,
ee2fce28-59db-4014-a550-5b43f289183d,
f882e270-5804-4f67-be63-599dba30cc12,
8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627,
,
,
b2c792f8-1b1a-493f-8388-fe17cfc99931,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true
test failed: false, true, true, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9,
81902166-5563-4879-b345-eb7a086625ea,
8f539dfe-0634-42b6-8409-acef00b99289,
679ab034-ba16-4437-935c-e64f06433be9,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff,
6d3e0086-b2ae-468d-b231-683355928a4d,
28ad0d17-5e84-40ee-af86-a5c9175e415d,
1c564983-4c6a-4bea-be2a-dcccb8295bef,
638188b4-c2fc-4133-8b65-797114180f04
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2,
ffeb2f66-c77b-474f-a305-a04f4afc87af,
b2954dd3-3942-497b-9059-edc1f51db921,
294cc579-3da1-4084-9f1f-59c61c553cf9,
02e3522b-e907-4849-98dd-593d197989e0
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36,
9194ae03-b335-40f3-af6f-718e7be9c8ae,
f1c5e294-1695-4474-9704-2d549880ce28,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
c8baedb9-0082-4eec-9aca-059c23d731c5,
73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159,
fdbdfe87-3692-40b7-bc31-76b969b98541,
f84e10ce-2813-440f-bda8-0a17d63d0c90,
c602aba9-2920-4010-a515-bd9d1c8539d8,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
52d604c6-2ce9-4838-934f-3e90c4bcda12,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
76391515-fb72-4c62-a581-0a8c545f276b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
H2 connection
HTTP/2 is a web connection protocol introduced in 2015. Some browsers re-use HTTP/2 connections across websites and can thus be used to track users.
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
ab578407-370d-4f49-b646-146a5387984b,
1a009336-8fc6-4c29-9156-8b7703d81ecb,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
aaafbb05-7196-4933-bb52-b72db6df608a,
d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1,
a7f946cf-faa8-4c53-becc-c6519f6bba4f,
ee2fce28-59db-4014-a550-5b43f289183d,
f882e270-5804-4f67-be63-599dba30cc12,
8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627,
528a685d-63c8-4a8c-88ec-037d368af791,
30d559cc-0031-4a5b-a870-4f11b6a100a0,
b2c792f8-1b1a-493f-8388-fe17cfc99931,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9,
81902166-5563-4879-b345-eb7a086625ea,
8f539dfe-0634-42b6-8409-acef00b99289,
679ab034-ba16-4437-935c-e64f06433be9,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff,
6d3e0086-b2ae-468d-b231-683355928a4d,
28ad0d17-5e84-40ee-af86-a5c9175e415d,
1c564983-4c6a-4bea-be2a-dcccb8295bef,
638188b4-c2fc-4133-8b65-797114180f04
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2,
ffeb2f66-c77b-474f-a305-a04f4afc87af,
b2954dd3-3942-497b-9059-edc1f51db921,
294cc579-3da1-4084-9f1f-59c61c553cf9,
02e3522b-e907-4849-98dd-593d197989e0
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36,
9194ae03-b335-40f3-af6f-718e7be9c8ae,
f1c5e294-1695-4474-9704-2d549880ce28,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
c8baedb9-0082-4eec-9aca-059c23d731c5,
73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159,
fdbdfe87-3692-40b7-bc31-76b969b98541,
f84e10ce-2813-440f-bda8-0a17d63d0c90,
c602aba9-2920-4010-a515-bd9d1c8539d8,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
52d604c6-2ce9-4838-934f-3e90c4bcda12,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
76391515-fb72-4c62-a581-0a8c545f276b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
H3 connection
HTTP/3 is a new standard HTTP connection protocol, still in draft but widely supported by browsers. If it is not partitioned, it can be used to track users across websites.
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , eb61ef6d439aa70fa55453ebcc51d280, f1a2872ccde7bb78f9502d2c149dae2c, 81fc2475480fed298b69a5989daa592b, 835e2654b5bdbc6b5c7bc800103c9967
result, different first party: , 0177df2385f347957bc1ca8eb89e3cf1, ff59861ba6e5e17d72f8a95498f7ad63, 88179034f0522444a8bf3bfd6e153213, 907452996ff21e2123950952ea99d5e7
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , cf32d0b2b10a923e60584d909588b2b7, 5b2cdedbc2f8a70b59ded642d23e3006, 77396ec0c99a95c01fa4db2e5c68c844, fc033a62253f378508ccb072d46540de
result, different first party: , 92d18b66f68bf12248f277e797193cee, 0ae9062ef67206aeece4cd404e49f4d3, 063e234a7c691f0afa33b174a048d5e5, e065d5940c4d4b8e093ca58aa3e47263
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , 4290555463ef6e3e64ff30685fd1b689, 44cbe7536773c31107779bceadfab5fd, 7fc3d0f794c5a059b71d6093db8deee0, 2811c27e9726978a086f296aec02563a
result, different first party: , 26c4731f88b729fe29036c0f63cb005c, 140f4172cd2da2d57714a76fa8a6cf78, c4b2c136a46374730417b15fd0d7c04d, d86c0692889645023f3af5b915e4be18
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , 15b50e5df7960c2fc29d5318e14e4098, 59037b73c01f7f5f2086841a3063efcd, 928bbf732eb9d08d80ec03566339dd6f, 77706d687b8085b9d934a8005bc33dc8
result, different first party: , ac330d5d7d3d60bf9a678629c236c088, 47f0c072d1cfc92b6f6eced4f5f47285, 3ba3c896b276e80cc2310ed0d6b3cddb, f123b53f65fccf0cb1a1f740ceab7fae
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , 557a77a3980fd46885d80b587b8b6472, 510ecc4544310b9b537c37b99887ce88, 5996f106beb42c9bed0ed6a47b6a834d, a6861dc909d4b252a07cb82336652d46
result, different first party: , 92b473553dd763471259766ab5490603, d5fb7e4757697684203a08f006132962, e9eed8e00a73a416e8668b34daf7c745, 013aeceee7e8a4e0c7b5aec14e3410c6
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , 2cd00d22d43cd25667a212ac58149dbb, 071b13db86a0cc6ef8fc237c3c325f0d, 354a0ad0b9b3461c5070c1a4c472da57, 2f6d11dc6f6ba47c12b29ece9eaf5e3f
result, different first party: , 9c8d80865d63e42e11285d2e2e5ffc30, ee9394586d80f59d8c257e22212ec70f, 076a5ce902e6105c4151a45677aec77c, 6b421bb4e36f2170de77cfd6de0ef8e3
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , 868011b80fdbf4bcefaccb46dc15c64f, 1a92923a19596b7e28eff9a57bba72ae, eef43c6df9501a4066a65eed39570b72, dceea1b39db157c1cd861971e9752efb
result, different first party: , af5b4e64e6b13f6cc71abb5f0bbc8811, 6a7cb90a4c13d90f8e9732700988af8e, 6d68827b2a964b12209df90a27a81e2d, 240ccabd7664a7e5a0525c255e4d6780
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , c01d4de0323df504100686f6d31a9d74, 15c6d0ead417ac5020dfe9519741edd9, 0de67f6e9974089b284ade10a6cb3d65, 9ed651f80ebc423e0de62861ad38d106
result, different first party: , 1561312fb0ff59677718069c3b85ae74, 469058648454066f0da3c1fda318e386, 959794c1bcac4b0b278fb6f620f69f60, de24fdfed38ca083380282fbe18bf365
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
HSTS cache
The HTTP Strict-Transport-Security response header allows a website to signal that it should only be accessed via HTTPS. The browser remembers this directive in a database, but if this database is not partitioned, then it can be used to track users across websites."
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
HSTS cache (fetch)
The HTTP Strict-Transport-Security response header allows a website to signal that it should only be accessed via HTTPS. The browser remembers this directive in a database, but if this database is not partitioned, then it can be used to track users across websites."
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
ab578407-370d-4f49-b646-146a5387984b,
1a009336-8fc6-4c29-9156-8b7703d81ecb,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
aaafbb05-7196-4933-bb52-b72db6df608a,
d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1,
a7f946cf-faa8-4c53-becc-c6519f6bba4f,
ee2fce28-59db-4014-a550-5b43f289183d,
f882e270-5804-4f67-be63-599dba30cc12,
8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627,
528a685d-63c8-4a8c-88ec-037d368af791,
30d559cc-0031-4a5b-a870-4f11b6a100a0,
b2c792f8-1b1a-493f-8388-fe17cfc99931,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9,
81902166-5563-4879-b345-eb7a086625ea,
8f539dfe-0634-42b6-8409-acef00b99289,
679ab034-ba16-4437-935c-e64f06433be9,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff,
6d3e0086-b2ae-468d-b231-683355928a4d,
28ad0d17-5e84-40ee-af86-a5c9175e415d,
1c564983-4c6a-4bea-be2a-dcccb8295bef,
638188b4-c2fc-4133-8b65-797114180f04
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2,
ffeb2f66-c77b-474f-a305-a04f4afc87af,
b2954dd3-3942-497b-9059-edc1f51db921,
294cc579-3da1-4084-9f1f-59c61c553cf9,
02e3522b-e907-4849-98dd-593d197989e0
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36,
9194ae03-b335-40f3-af6f-718e7be9c8ae,
f1c5e294-1695-4474-9704-2d549880ce28,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
c8baedb9-0082-4eec-9aca-059c23d731c5,
73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159,
fdbdfe87-3692-40b7-bc31-76b969b98541,
f84e10ce-2813-440f-bda8-0a17d63d0c90,
c602aba9-2920-4010-a515-bd9d1c8539d8,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
52d604c6-2ce9-4838-934f-3e90c4bcda12,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
76391515-fb72-4c62-a581-0a8c545f276b
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
ab578407-370d-4f49-b646-146a5387984b,
1a009336-8fc6-4c29-9156-8b7703d81ecb,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
aaafbb05-7196-4933-bb52-b72db6df608a,
d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1,
a7f946cf-faa8-4c53-becc-c6519f6bba4f,
ee2fce28-59db-4014-a550-5b43f289183d,
f882e270-5804-4f67-be63-599dba30cc12,
8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627,
528a685d-63c8-4a8c-88ec-037d368af791,
30d559cc-0031-4a5b-a870-4f11b6a100a0,
b2c792f8-1b1a-493f-8388-fe17cfc99931,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9,
81902166-5563-4879-b345-eb7a086625ea,
8f539dfe-0634-42b6-8409-acef00b99289,
679ab034-ba16-4437-935c-e64f06433be9,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff,
6d3e0086-b2ae-468d-b231-683355928a4d,
28ad0d17-5e84-40ee-af86-a5c9175e415d,
1c564983-4c6a-4bea-be2a-dcccb8295bef,
638188b4-c2fc-4133-8b65-797114180f04
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2,
ffeb2f66-c77b-474f-a305-a04f4afc87af,
b2954dd3-3942-497b-9059-edc1f51db921,
294cc579-3da1-4084-9f1f-59c61c553cf9,
02e3522b-e907-4849-98dd-593d197989e0
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36,
9194ae03-b335-40f3-af6f-718e7be9c8ae,
f1c5e294-1695-4474-9704-2d549880ce28,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
c8baedb9-0082-4eec-9aca-059c23d731c5,
73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159,
fdbdfe87-3692-40b7-bc31-76b969b98541,
f84e10ce-2813-440f-bda8-0a17d63d0c90,
c602aba9-2920-4010-a515-bd9d1c8539d8,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
52d604c6-2ce9-4838-934f-3e90c4bcda12,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
76391515-fb72-4c62-a581-0a8c545f276b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
locks
navigator.locks (only supported in some browsers) allows scripts on multiple tabs to coordinate. If this API is not partitioned, it can be used for cross-site tracking.
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
script cache
Caching of scripts in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
ServiceWorker
The ServiceWorker API allows websites to run code in the background and store content in the browser for offline use. If a ServiceWorker can be accessed from multiple websites, it can be abused to track users across sites.
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
SharedWorker
The SharedWorker API allows scripts from multiple tabs to share a background thread of computation. If SharedWorker is not partitioned, then it can be abused to shared data between websites in your browser.
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
TLS Session ID
The TLS protocol is used by HTTPS to make connections secure. If the browser were to re-use a TLS session, then the session ID could be used to track users across websites.
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
071d784d3f95e8f56e7bc96c5454ebd84efe8621a61b4777648bf505c9ae7d61,
d0c2a3d40588eba0c4a1b6b113530fd10831e589f94e1be13f1de45d75226118,
325323d8c5b84518f177680bd30da9a5bf532ee4ea98c998f0dadb3fd82afc64,
776c14905fa7a72a208ba9c2d072258044090c242d2f50963db08c3011dcec1e,
c0b815364eb46fe877effb42b816524d2d75413670f32d174ce9a0c950097275
result, different first party:
0086a65b766d826e870d120aa623cc063cc27268f7f73078e39c81af5224964b,
f8a31113bd7fdabde4da96980428976d6439151b544154f96caa2cb4f340a9e2,
ce1592585cc6324d721bf973bbe4b13ac1fcfb96caeb3ae3bcd7108594e2e32b,
1ed8d331e80f21b72e3011b211c848adc815b975869c80feff27420be72339de,
df2509e4fd35ea9ad4c52abfb5f702e5f89168f4835d6a62dc75edd30c259c76
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
e4237df0a75fd2c88b91958ae30288bf8ca4af452f92e2b324765872b9c5a86b,
723d5af223c11450cbdba771a9f90ea419b2728954be7c21bab8cb93e240bb5f,
7f8dd2dd49a853b1173e12dbbc086e8e10592bde39c1079a1508615b1f9efe7c,
a93a5aaa98b8e560446911fb480366fb59e0d6e41560994f38d5bac88278797c,
03632b08c587012a7a760d12d7cd9e50b3ed6397a626e447560f346745b8e3bc
result, different first party:
100ce9722990c5199e39a1fe096ebb6c981237e86144c653881521538f13cb02,
4ce88a9aa3bdb7d766ed0cd7055c58d6811892cdd5994fb4754d519043d5c7df,
96933a30144bfea06041785dc5938ddab76a791ff8bb4a665aeed6347149196f,
8eebcaf7a864d38ed8267b569ba56db6098a08f5afad7451d5172bc4ea599feb,
241d325a82a8c175a1dfc6f38f74fd0f5f4871e148b10f962611da9d382f595a
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
c4a82fac7c9bb33bbe7016c7bc83e9e0c64df1ef0f11aceaa89918a6f77fe13b,
46c738048dced169f567c2fe0f5e74a80a1f9aa743b5ef5ba0fbf82acf6773e0,
903ee1b851c212de0c71776dfbdc8f7123bbddee8fb6ad980ae47153a5c9b24b,
45a6a7383041c82b1729902fb31de45a43f27a7209bd3856591d4393af6138f2,
b4b2300f9acaa363113819d178f1887cf70d0a1e54b67917d91ac3ce3de37988
result, different first party:
128f65bd39c44e5c2bbb3adf12c6f40c7884800a3492078df9cc2ae88cc285da,
24bf276d07afcde9ee5aa80e56e3d43faccbf980be2e270239268733555d79ba,
72cd5f7a923bf295d2f1314b8b066d9eac6b0b81082c6957a5404d43ec231566,
9584854207f9fc690dfae47371b4c079df65a12d5958dce1e7451decc4cf2c08,
4bd3e8ac1e15af9f1c3561fe5067d68ae478383e647b5484d938189317a75835
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
46097bbdbd3bdec3d4a01a190c2b3060d705406019e1bb810358b84d8af91986,
8347d78d090f5e72c3df6257d5c7407da9c092cd36077d9b43dc0d92bc4ae874,
f5f417de31659ec335574e2a2afffd130788250058428512b083ac468c3e357a,
90610461bb20bd48f8a809cc984f9613da6ee9fe95152d66c79e505f4aecc93d,
4aee45cc6ee69d7b1c449c26a744269e613d72dc30331851aff8c26b26008b1e
result, different first party:
1ce6f5c776b9465d59894af98a6a3f96f7d9e2a71e9b28c41dc907021a947dbb,
f040d1718621405bcf5577f8780a0e2fcf379c0dbcf0ef830dfe4eec1a31b941,
46c0f92e6c1d0a9f78768d4df0ef97810535f914bdd3dc207bf11a78127571b5,
b2729034aca37987584849e799ec3b978010c338b86b405f50b823b715354686,
ae797e5ff16349de67d96882cf0ff633075b8b675ac81fd14c754e180d0550bc
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
1058e5c1fe4ff4b2eb3ef09bb27c4c3b27562bbe8c41df5256d0f799fbb5bea0,
c575412ddf35f5790125b65fbc2178cc59d553874683699e158176f8db4f6748,
f3e2c61ed16589859c0403606b5df6f5e3773dc44d0ccfcac9a1b3209a8f963b,
1328b1f4dfd9f54f3bc9f5d4af4f13e1e857c9dd70b569ffc4a40d41c09802ba,
752573328ce2ba33cb45f8ffddc47958b2da76dfe0bef4e4a407f94d4192cc27
result, different first party:
d9675dd103e8efa95a183e8bff12c11a87379d68afc551eacb4c28f8f75ce567,
1e3228142730b120965ef67cd1d65030f08530451c54b61880c32b18d6fd29a4,
161117fd9c08a0ac1f90f4d7f389446a130512221ad453638075c65d5c2b784e,
3d5fbda2a6828effe5f07bbbc489a3cce3cec10d72bd0a0dc9c4c743b8ec4516,
bcb3b0d7a4ca5d9b8f4eb2eaa5d89beffb494f560d4c317b33719d78851bf2bb
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
ec9c980ebe3861e6d63bfe08b7f30d516d1fe504a092076b6d76a093b5b2f17f,
ac8bda4e1d443889295fe421c9fcbb513f52d3b90d3da2bcfef9229f9898a354,
bd715f80f1ffa7eaeee3d59ce82ce15247432924474c0e21cde7e18c7d3cafd8,
cb4502f1a41a504b01e0056a51a628047cb83040c11e8e9969d3f2e89a3bdb4f,
4ea708503505650e8cee3abbc4767ecda9218d37d7a29c3e52a6464c9d4b94c7
result, different first party:
52a8bf023c09cd3e5713bc93c78a70f6f38f6e5b7339301df94948a8c4e0aa50,
d06c546e140ed6b6bdb0e78f5067fae53fff5ca03de21d99d01814225b92aede,
d4709ba5cd7daf1f248cb6f7f51e100a78cf87e940d02f4173d3a3925b7e2666,
a18abd740f296f0a31f34204322ae0d36f6010061966248240c4b98939981a94,
09d59561cb1c014881c69c16e674e91c1b1ade8197eb47372baea42369a213a2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
d53999331567cc58331f5f2c49e0efb980bc081a498e2722a1c93829cf868888,
4ac2f99518a606afd026c4564708dc7b3d4d47d31a66a365472bf408ba169faf,
0fbec65814d7b8ceb810c62dab91fff7e2340f0bdbd2ebce41ebfbc15ba24496,
89005aaf860b2c3199b2e06020d832f2cd63ae4051478a2e640499284e40daf9,
77f1ef902b7151726bfe3438ecea00338d2fc989ea60bfbbca0d1c55e74cf103
result, different first party:
7489f5a011e0070ea8ca72d5deaa98e0066d10a8ab997b5d9f84579823ba5204,
15d2a62b4d22b015c6cc97a71f883601d452ac4d4954f734682e10661fde896a,
40cec8532b43a0001ba49a458fe45a4f45423659d5940479ca805071f7800c48,
4a083d7c49c52ec3a51f54eb8bcf192b183ead05186fd8257dc176a306ac5750,
cbce89e2fbae5b2a457e21a511fdfbd2357a986c0ef949ede40e1229555f3db4
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
aea2b8126f8e38fbc24241461188d4fe455c1921a65d0519eb3000b46cb37529,
fb75565fa7c76383a4a347969b7af2712ffe23be84ee3384e09b16e088e0edf2,
19420396877aeed6beedd107a8559a46ef3f309ab4ef2a874fc21407b529112f,
a26f672f8d31a66d48c49d0cdd4a43ca93364b8dab8f30a3d79298b7092e84f7,
05f33395e69978fcec77b2df5eb0f96197f2316ca3427de5a74115c508099d1f
result, different first party:
2436116e72876673a4f7a9a61cec762d6a2fc464577df0e1699b12bea06598f1,
921f8e268cca850ed3d5f83db9c1485ab94d59965208d27f67c66040ac6873f2,
a4b0f1a34c2f693fc40d6e8b1a2b3af273659a159edec598c6d174959d864536,
ca63ed0f9c3da4615793a13dfb64271c97ab62a638d279f9cfeb14f738acc97b,
a17968cb24e4bc37321bd5a049493b62f5f7945e0b2a155224bbf56112ecbc97
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
049a5d0384759c669e8410609801902b8681c8d160cd7b64746300b5fc6d3fe5,
6646d25ea238706308d9f9006cdf3356a4f0f74756516dbc8afa59b91305fe0a,
9067b3be76dbe19922f0f5eafc4d82f4862e63d44d47ac240ff3f12ec9623c61,
09b8ba50a20c3adf0cb282bd539461164c49836492066c472822980fbc42bdf1,
e7fec1433fc484aef030f2cd71e59a9d97b4cc49e19c12f7d3e5745861e6b3ed
result, different first party:
5a2b35ddc76570c5966c2a54b470290887f426b4aab8658d6b7cdff8d192c721,
6d94053adaa098c434185d9b3d58c255f3b822ff984412cc25b6b525196306b5,
45b8622d491e126c21232a7efd09fa4ea1b901aac8ce396ae6152b617747a3d1,
43e66c8f66d62bc43ae73df87b70c3db6ee238ccdf84a566e769d1a5d9cfe611,
4f94b4d6c038c9bc94a839ac28e84572d2098c358bd6fcd7b666de76c217f999
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
6c2bb03452744b63693722a1e293f827d2fc47ede5e7f671b3250979e588aa05,
4a18706020192306aa7e285574253e260db7dfa3436d9cb7f5f183201ff7082a,
198d6bcfcfa9648ca9b12c274a59a777d5253a4ef16b5c810137b755c50bad75,
8bad0a42276a5a7a24049e5d7c8da5a9abf6fb4d27a09dd2395ad4828ecbf105,
13dab34232788707d52c8b0b71c48b4a0e94d6058838134b264d1372304507b0
result, different first party:
131f807985762966f4532c2f54d42bb3168f271e553b413f5e305cb0bdc622d1,
017e7805f226a88efb2fe08ab522c8a82db47c5f4adfca58f68fb48abc614b05,
aa6292ad7302c9b2eae26d48dd35ecf44e072281e1bc491abe5f8b3204424d2d,
14f9ed21159308caff23ea24cee8294190650a78923555e995a7cc0aa5d91db7,
55be26e083c91b3655a7a8d9e1b3b590ac253b7b367ac43748c63608595c1dec
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 2, 2, 2, 2, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Navigation testsWhich browsers prevent websites from sharing tracking data when you click on a link?
When you click a hyperlink to navigate your browser from one site to another, certain browser APIs allow the first site to communicate to the second site. These privacy vulnerabilities can be fixed by introducing new limits on how much data is transfered between sites.',
document.referrer
The Referer [sic] request header is a mechanism used by browsers to let a website know where the user is visiting from. This header is inherently tracking users across websites. In recent times, browsers have switched to a policy of trimming a referrer to convey less tracking information, but Referer continues to convey cross-site tracking data by default.
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
sessionStorage
The sessionStorage API is similar to the localStorage API, but it does not persist across tabs or across browser sessions. Nonetheless, it can be used to track users if they navigate from one website to another. This tracking can be thwarted by partitioning sessionStorage between websites.
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
ab578407-370d-4f49-b646-146a5387984b,
1a009336-8fc6-4c29-9156-8b7703d81ecb,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
aaafbb05-7196-4933-bb52-b72db6df608a,
d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
bc961a97-730f-4b98-9434-da4795a8b0f1,
a7f946cf-faa8-4c53-becc-c6519f6bba4f,
ee2fce28-59db-4014-a550-5b43f289183d,
f882e270-5804-4f67-be63-599dba30cc12,
8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
aeb5290e-1534-4281-92c9-893e65c28627,
528a685d-63c8-4a8c-88ec-037d368af791,
30d559cc-0031-4a5b-a870-4f11b6a100a0,
b2c792f8-1b1a-493f-8388-fe17cfc99931,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
46ab308c-e44d-4c84-9b89-8630607096f9,
81902166-5563-4879-b345-eb7a086625ea,
8f539dfe-0634-42b6-8409-acef00b99289,
679ab034-ba16-4437-935c-e64f06433be9,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
62bd2dbc-8547-43c4-8387-ef38495a10ff,
6d3e0086-b2ae-468d-b231-683355928a4d,
28ad0d17-5e84-40ee-af86-a5c9175e415d,
1c564983-4c6a-4bea-be2a-dcccb8295bef,
638188b4-c2fc-4133-8b65-797114180f04
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2,
ffeb2f66-c77b-474f-a305-a04f4afc87af,
b2954dd3-3942-497b-9059-edc1f51db921,
294cc579-3da1-4084-9f1f-59c61c553cf9,
02e3522b-e907-4849-98dd-593d197989e0
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
83fe9d03-30ee-4948-a9bc-5218672c2c36,
9194ae03-b335-40f3-af6f-718e7be9c8ae,
f1c5e294-1695-4474-9704-2d549880ce28,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
df92863b-7453-462d-8fab-f15094cfe5af,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
c8baedb9-0082-4eec-9aca-059c23d731c5,
73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
0091eaa4-d94b-4aae-890d-20215c2fb159,
fdbdfe87-3692-40b7-bc31-76b969b98541,
f84e10ce-2813-440f-bda8-0a17d63d0c90,
c602aba9-2920-4010-a515-bd9d1c8539d8,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
9226d658-d9dc-43e4-b613-949c8e04ec0b,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
52d604c6-2ce9-4838-934f-3e90c4bcda12,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
76391515-fb72-4c62-a581-0a8c545f276b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
window.name
The window.name API allows websites to store data that will persist after the user has navigated the tab to a different website. This mechanism could be partitioned so that data is not allowed to persist between websites.
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_ab578407-370d-4f49-b646-146a5387984b,
name_1a009336-8fc6-4c29-9156-8b7703d81ecb,
name_9ffac5bb-9da0-47c4-b155-fdfcafab4e9d,
name_aaafbb05-7196-4933-bb52-b72db6df608a,
name_d0134525-2c97-46f5-a372-2e6c225c3019
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_bc961a97-730f-4b98-9434-da4795a8b0f1,
name_a7f946cf-faa8-4c53-becc-c6519f6bba4f,
name_ee2fce28-59db-4014-a550-5b43f289183d,
name_f882e270-5804-4f67-be63-599dba30cc12,
name_8bb057b5-ccc8-478a-8d42-5651ab499e89
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_aeb5290e-1534-4281-92c9-893e65c28627,
name_528a685d-63c8-4a8c-88ec-037d368af791,
name_30d559cc-0031-4a5b-a870-4f11b6a100a0,
name_b2c792f8-1b1a-493f-8388-fe17cfc99931,
name_3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_46ab308c-e44d-4c84-9b89-8630607096f9,
name_81902166-5563-4879-b345-eb7a086625ea,
name_8f539dfe-0634-42b6-8409-acef00b99289,
name_679ab034-ba16-4437-935c-e64f06433be9,
name_7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_62bd2dbc-8547-43c4-8387-ef38495a10ff,
name_6d3e0086-b2ae-468d-b231-683355928a4d,
name_28ad0d17-5e84-40ee-af86-a5c9175e415d,
name_1c564983-4c6a-4bea-be2a-dcccb8295bef,
name_638188b4-c2fc-4133-8b65-797114180f04
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_18670d8e-7445-4b90-b5b9-a6fc14ac99c2,
name_ffeb2f66-c77b-474f-a305-a04f4afc87af,
name_b2954dd3-3942-497b-9059-edc1f51db921,
name_294cc579-3da1-4084-9f1f-59c61c553cf9,
name_02e3522b-e907-4849-98dd-593d197989e0
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_83fe9d03-30ee-4948-a9bc-5218672c2c36,
name_9194ae03-b335-40f3-af6f-718e7be9c8ae,
name_f1c5e294-1695-4474-9704-2d549880ce28,
name_1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0,
name_e0a5ca1a-9191-45e9-933b-b7e7101632e6
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_df92863b-7453-462d-8fab-f15094cfe5af,
name_2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5,
name_91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e,
name_c8baedb9-0082-4eec-9aca-059c23d731c5,
name_73afc3df-3d35-4c5c-8056-96142486ae81
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_0091eaa4-d94b-4aae-890d-20215c2fb159,
name_fdbdfe87-3692-40b7-bc31-76b969b98541,
name_f84e10ce-2813-440f-bda8-0a17d63d0c90,
name_c602aba9-2920-4010-a515-bd9d1c8539d8,
name_23ae349e-b48f-4fb7-afbf-4f7ea763b7c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_9226d658-d9dc-43e4-b613-949c8e04ec0b,
name_bf58860c-17d5-42df-b2cb-8eb3c2b042a4,
name_52d604c6-2ce9-4838-934f-3e90c4bcda12,
name_fdfe4f16-304a-4cb6-81a3-a7e55edf2817,
name_76391515-fb72-4c62-a581-0a8c545f276b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
HTTPS testsWhich browsers prevent unencrypted network connections?
HTTPS is the protocol that web browsers use to connect securely to websites. When HTTPS is being used, the connection is encrypted so that third parties on the network cannot read content being sent between the server and your browser. In the past, insecure connections were the default and websites would need to actively request that a browser use HTTPS. Now the status quo is shifting, and browser makers are moving toward a world where HTTPS is the default protocol.`
Insecure website warning
Checks to see if the browser stops loading an insecure website and warns the user before giving them the option to continue. Known as HTTPS-Only Mode in some browsers.
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Upgradable address
Checks to see if an insecure address entered into the browser's address bar is upgraded to HTTPS whenever possible.
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Upgradable hyperlink
Checks to see if the user has clicked on a hyperlink to an insecure address, if the browser upgrades that address to HTTPS whenever possible.
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Upgradable image
Checks to see if the browser attempts to upgrade an insecure address for an image to HTTPS whenever possible.
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Failed
passed: false, false, false, false, false
result:
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Failed
passed: false, false, false, false, false
result:
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Failed
passed: false, false, false, false, false
result:
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Failed
passed: false, false, false, false, false
result:
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Failed
passed: false, false, false, false, false
result:
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Failed
passed: false, false, false, false, false
result:
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Upgradable script
Checks to see if the browser attempts to upgrade an insecure address for an script to HTTPS whenever possible.
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Misc testsWhich browsers provide additional assorted privacy protections?
This category includes tests for the presence of miscellaneous privacy features
ECH enabled
Encrypted Client Hello (ECH) is a new protocol that hides the website you are visiting from third-party network eavesdroppers.
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
GPC enabled first-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a website not to sell the user's personal data to third parties. This test checks to see if the GPC header is sent by default to the top-level website.
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
GPC enabled third-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a visited website not to sell the user's personal data to other parties. This test checks to see if the GPC header is sent to third-party elements on the web page.
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
IP address leak
IP addresses can be used to uniquely identify a large percentage of users. A proxy, VPN, or Tor can mask a user's IP address.
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Stream isolation
Browsers that use Tor can use a different Tor circuit per top-level website.
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Tor enabled
The Tor network sends the browser's web requests through a series of relays to hide a user's IP address, thereby helping to mask their identity and location. This test checks to see if the Tor network is being used by default.
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Fingerprinting resistance testsWhich browsers hide what's unique about your device?
Fingerprinting is a technique trackers use to uniquely identify you as you browse the web. A fingerprinting script will measure several characteristics of your browser and, combining this data, will build a fingerprint that may uniquely identify you among web users. Browsers can introduce countermeasures, such as minimizing the distinguishing information disclosed by certain web APIs so your browser is harder to pick out from the crowd (so-called 'fingerprinting resistance').`,
Media query screen height
Height of the user's screen in pixels.
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Media query screen width
Width of the user's screen in pixels.
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
outerHeight
Height of the browser window in pixels, including browser chrome.
Failed
expression: outerHeight
desired expression: undefined
actual value: 543,543,543,543,543
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 546,546,546,546,546
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 561,561,561,561,561
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 526,526,526,526,526
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 547,547,547,547,547
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 555,555,555,555,555
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 508,508,508,508,508
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
screen.height
Height of the user's screen, in pixels.
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 667,667,667,667,667
desired value: undefined
passed: false,false,false,false,false
screen.width
Width of the user's screen, in pixels.
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 375,375,375,375,375
desired value: undefined
passed: false,false,false,false,false
screenX
Position, in pixels, of the left edge of the browser window on screen.
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
screenY
Position, in pixels, of the top edge of the browser window on screen.
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Tracking query parameter testsWhich browsers remove URL parameters that can track you?
When you browse from one web page to another, tracking companies will frequently attach a 'tracking query parameter' to the address of the second web page. That query parameter may contain a unique identifier that tracks you individually as you browse the web. And these query parameters are frequently synchronized with cookies, making them a powerful tracking vector. Web browsers can protect you from known tracking query parameters by stripping them from web addresses before your browser sends them. (The set of tracking query parameters tested here was largely borrowed from Brave.)`
__hsfp
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
__hssc
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
__hstc
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
__s
Drip.com email address tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
_hsenc
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
_openstat
Yandex tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
dclid
DoubleClick Click ID (Google)
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
fbclid
Facebook Click Identifier
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
gclid
Google Click Identifier
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
hsCtaTracking
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
mc_eid
Mailchimp Email ID (email recipient's address)
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
mkt_tok
Adobe Marketo tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
ml_subscriber
MailerLite email tracking
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
ml_subscriber_hash
MailerLite email tracking
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
msclkid
Microsoft Click ID
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
oly_anon_id
Omeda marketing 'anonymous' customer id
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
oly_enc_id
Omeda marketing 'known' customer id
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
rb_clickid
Unknown high-entropy tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
s_cid
Adobe Site Catalyst tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
vero_conv
Vero tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
vero_id
Vero tracking parameter
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
wickedid
Wicked Reports e-commerce tracking
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
yclid
Yandex Click ID
Passed
passed: true, true, true, true, true
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Failed
value: 9128313973981925
passed: false, false, false, false, false
Tracker content blocking testsWhich browsers block important known tracking scripts and pixels?
When you visit a web page, it frequently has third-party embedded tracking content, such as scripts and tracking pixels. These embedded components spy on you. Some browsers and browser extensions maintain list of tracking companies and block their content from being loaded. This section checks to see if a browser blocks 20 of the largest trackers listed by https://whotracks.me.`
Adobe
Tests whether the browser blocks the page from loading the tracker at https://munchkin.marketo.net/munchkin.js
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Adobe Audience Manager
Tests whether the browser blocks the page from loading the tracker at https://dpm.demdex.net/ibs
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Amazon adsystem
Tests whether the browser blocks the page from loading the tracker at https://s.amazon-adsystem.com/dcm
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
AppNexus
Tests whether the browser blocks the page from loading the tracker at https://ib.adnxs.com/px?id=178248&t=1
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Bing Ads
Tests whether the browser blocks the page from loading the tracker at https://bat.bing.com/bat.js
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Chartbeat
Tests whether the browser blocks the page from loading the tracker at https://static.chartbeat.com/js/chartbeat.js
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Criteo
Tests whether the browser blocks the page from loading the tracker at https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
DoubleClick (Google)
Tests whether the browser blocks the page from loading the tracker at https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Facebook tracking
Tests whether the browser blocks the page from loading the tracker at https://connect.facebook.net/en_US/fbevents.js
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Google (third-party ad pixel)
Tests whether the browser blocks the page from loading the tracker at https://www.google.com/pagead/1p-user-list/
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Google Analytics
Tests whether the browser blocks the page from loading the tracker at https://google-analytics.com/urchin.js
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Google Tag Manager
Tests whether the browser blocks the page from loading the tracker at https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Index Exchange
Tests whether the browser blocks the page from loading the tracker at https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
New Relic
Tests whether the browser blocks the page from loading the tracker at https://js-agent.newrelic.com/nr-1212.min.js
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Quantcast
Tests whether the browser blocks the page from loading the tracker at https://pixel.quantserve.com/pixel
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Scorecard Research Beacon
Tests whether the browser blocks the page from loading the tracker at https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Taboola
Tests whether the browser blocks the page from loading the tracker at https://trc.taboola.com/futureplc-tomsguide/trc/3/json
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Twitter pixel
Tests whether the browser blocks the page from loading the tracker at https://t.co/i/adsct
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Yandex Ads
Tests whether the browser blocks the page from loading the tracker at https://yandex.ru/ads/system/header-bidding.js
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Cross-session first-party tracking testsWhich browsers prevent websites from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow websites ("first parties") to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h3, h2, h3, h2
result, different session: h3, h2, h3, h2, h3
unsupported: true, false, true, false, true
passed: , true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
ab578407-370d-4f49-b646-146a5387984b_1p,
1a009336-8fc6-4c29-9156-8b7703d81ecb_1p,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_1p,
aaafbb05-7196-4933-bb52-b72db6df608a_1p,
d0134525-2c97-46f5-a372-2e6c225c3019_1p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p
result, different session:
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p,
c8862fe6-10af-4325-82d5-bc125ac58827_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p
result, different session:
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p
result, different session:
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p,
18747aa0-a493-4b2f-8684-a70dc7fadf6a_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_1p,
6d3e0086-b2ae-468d-b231-683355928a4d_1p,
28ad0d17-5e84-40ee-af86-a5c9175e415d_1p,
1c564983-4c6a-4bea-be2a-dcccb8295bef_1p,
638188b4-c2fc-4133-8b65-797114180f04_1p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_1p,
9194ae03-b335-40f3-af6f-718e7be9c8ae_1p,
f1c5e294-1695-4474-9704-2d549880ce28_1p,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_1p,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_1p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
df92863b-7453-462d-8fab-f15094cfe5af_1p,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_1p,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_1p,
c8baedb9-0082-4eec-9aca-059c23d731c5_1p,
73afc3df-3d35-4c5c-8056-96142486ae81_1p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_1p,
fdbdfe87-3692-40b7-bc31-76b969b98541_1p,
f84e10ce-2813-440f-bda8-0a17d63d0c90_1p,
c602aba9-2920-4010-a515-bd9d1c8539d8_1p,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_1p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_1p,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p,
52d604c6-2ce9-4838-934f-3e90c4bcda12_1p,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_1p,
76391515-fb72-4c62-a581-0a8c545f276b_1p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
ab578407-370d-4f49-b646-146a5387984b_1p_http,
1a009336-8fc6-4c29-9156-8b7703d81ecb_1p_http,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_1p_http,
aaafbb05-7196-4933-bb52-b72db6df608a_1p_http,
d0134525-2c97-46f5-a372-2e6c225c3019_1p_http
result, different session:
ab578407-370d-4f49-b646-146a5387984b_1p_http,
1a009336-8fc6-4c29-9156-8b7703d81ecb_1p_http,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_1p_http,
aaafbb05-7196-4933-bb52-b72db6df608a_1p_http,
d0134525-2c97-46f5-a372-2e6c225c3019_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p_http,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p_http,
ee2fce28-59db-4014-a550-5b43f289183d_1p_http,
f882e270-5804-4f67-be63-599dba30cc12_1p_http,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p_http
result, different session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p_http,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p_http,
ee2fce28-59db-4014-a550-5b43f289183d_1p_http,
f882e270-5804-4f67-be63-599dba30cc12_1p_http,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
aeb5290e-1534-4281-92c9-893e65c28627_1p_http,
528a685d-63c8-4a8c-88ec-037d368af791_1p_http,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p_http,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p_http,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p_http
result, different session:
aeb5290e-1534-4281-92c9-893e65c28627_1p_http,
528a685d-63c8-4a8c-88ec-037d368af791_1p_http,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p_http,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p_http,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p_http,
81902166-5563-4879-b345-eb7a086625ea_1p_http,
8f539dfe-0634-42b6-8409-acef00b99289_1p_http,
679ab034-ba16-4437-935c-e64f06433be9_1p_http,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p_http
result, different session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p_http,
81902166-5563-4879-b345-eb7a086625ea_1p_http,
8f539dfe-0634-42b6-8409-acef00b99289_1p_http,
679ab034-ba16-4437-935c-e64f06433be9_1p_http,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_1p_http,
6d3e0086-b2ae-468d-b231-683355928a4d_1p_http,
28ad0d17-5e84-40ee-af86-a5c9175e415d_1p_http,
1c564983-4c6a-4bea-be2a-dcccb8295bef_1p_http,
638188b4-c2fc-4133-8b65-797114180f04_1p_http
result, different session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_1p_http,
6d3e0086-b2ae-468d-b231-683355928a4d_1p_http,
28ad0d17-5e84-40ee-af86-a5c9175e415d_1p_http,
1c564983-4c6a-4bea-be2a-dcccb8295bef_1p_http,
638188b4-c2fc-4133-8b65-797114180f04_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_1p_http,
ffeb2f66-c77b-474f-a305-a04f4afc87af_1p_http,
b2954dd3-3942-497b-9059-edc1f51db921_1p_http,
294cc579-3da1-4084-9f1f-59c61c553cf9_1p_http,
02e3522b-e907-4849-98dd-593d197989e0_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_1p_http,
9194ae03-b335-40f3-af6f-718e7be9c8ae_1p_http,
f1c5e294-1695-4474-9704-2d549880ce28_1p_http,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_1p_http,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_1p_http
result, different session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_1p_http,
9194ae03-b335-40f3-af6f-718e7be9c8ae_1p_http,
f1c5e294-1695-4474-9704-2d549880ce28_1p_http,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_1p_http,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
df92863b-7453-462d-8fab-f15094cfe5af_1p_http,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_1p_http,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_1p_http,
c8baedb9-0082-4eec-9aca-059c23d731c5_1p_http,
73afc3df-3d35-4c5c-8056-96142486ae81_1p_http
result, different session:
df92863b-7453-462d-8fab-f15094cfe5af_1p_http,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_1p_http,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_1p_http,
c8baedb9-0082-4eec-9aca-059c23d731c5_1p_http,
73afc3df-3d35-4c5c-8056-96142486ae81_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_1p_http,
fdbdfe87-3692-40b7-bc31-76b969b98541_1p_http,
f84e10ce-2813-440f-bda8-0a17d63d0c90_1p_http,
c602aba9-2920-4010-a515-bd9d1c8539d8_1p_http,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_1p_http
result, different session:
0091eaa4-d94b-4aae-890d-20215c2fb159_1p_http,
fdbdfe87-3692-40b7-bc31-76b969b98541_1p_http,
f84e10ce-2813-440f-bda8-0a17d63d0c90_1p_http,
c602aba9-2920-4010-a515-bd9d1c8539d8_1p_http,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_1p_http,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p_http,
52d604c6-2ce9-4838-934f-3e90c4bcda12_1p_http,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_1p_http,
76391515-fb72-4c62-a581-0a8c545f276b_1p_http
result, different session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_1p_http,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p_http,
52d604c6-2ce9-4838-934f-3e90c4bcda12_1p_http,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_1p_http,
76391515-fb72-4c62-a581-0a8c545f276b_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
ab578407-370d-4f49-b646-146a5387984b_1p_js,
1a009336-8fc6-4c29-9156-8b7703d81ecb_1p_js,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_1p_js,
aaafbb05-7196-4933-bb52-b72db6df608a_1p_js,
d0134525-2c97-46f5-a372-2e6c225c3019_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p_js,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p_js,
ee2fce28-59db-4014-a550-5b43f289183d_1p_js,
f882e270-5804-4f67-be63-599dba30cc12_1p_js,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p_js
result, different session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p_js,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p_js,
ee2fce28-59db-4014-a550-5b43f289183d_1p_js,
f882e270-5804-4f67-be63-599dba30cc12_1p_js,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
aeb5290e-1534-4281-92c9-893e65c28627_1p_js,
528a685d-63c8-4a8c-88ec-037d368af791_1p_js,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p_js,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p_js,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p_js
result, different session:
aeb5290e-1534-4281-92c9-893e65c28627_1p_js,
528a685d-63c8-4a8c-88ec-037d368af791_1p_js,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p_js,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p_js,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p_js,
81902166-5563-4879-b345-eb7a086625ea_1p_js,
8f539dfe-0634-42b6-8409-acef00b99289_1p_js,
679ab034-ba16-4437-935c-e64f06433be9_1p_js,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p_js
result, different session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p_js,
81902166-5563-4879-b345-eb7a086625ea_1p_js,
8f539dfe-0634-42b6-8409-acef00b99289_1p_js,
679ab034-ba16-4437-935c-e64f06433be9_1p_js,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_1p_js,
6d3e0086-b2ae-468d-b231-683355928a4d_1p_js,
28ad0d17-5e84-40ee-af86-a5c9175e415d_1p_js,
1c564983-4c6a-4bea-be2a-dcccb8295bef_1p_js,
638188b4-c2fc-4133-8b65-797114180f04_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_1p_js,
ffeb2f66-c77b-474f-a305-a04f4afc87af_1p_js,
b2954dd3-3942-497b-9059-edc1f51db921_1p_js,
294cc579-3da1-4084-9f1f-59c61c553cf9_1p_js,
02e3522b-e907-4849-98dd-593d197989e0_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_1p_js,
9194ae03-b335-40f3-af6f-718e7be9c8ae_1p_js,
f1c5e294-1695-4474-9704-2d549880ce28_1p_js,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_1p_js,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
df92863b-7453-462d-8fab-f15094cfe5af_1p_js,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_1p_js,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_1p_js,
c8baedb9-0082-4eec-9aca-059c23d731c5_1p_js,
73afc3df-3d35-4c5c-8056-96142486ae81_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_1p_js,
fdbdfe87-3692-40b7-bc31-76b969b98541_1p_js,
f84e10ce-2813-440f-bda8-0a17d63d0c90_1p_js,
c602aba9-2920-4010-a515-bd9d1c8539d8_1p_js,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_1p_js,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p_js,
52d604c6-2ce9-4838-934f-3e90c4bcda12_1p_js,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_1p_js,
76391515-fb72-4c62-a581-0a8c545f276b_1p_js
result, different session: , bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p_js, , ,
unsupported: false, false, false, false, false
passed: true, false, true, true, true
test failed: false, false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_6276468469586456,
fake_5575180433264999,
fake_9876938708169847,
fake_8634549414351658,
fake_938271301212894
result, different session:
fake_6276468469586456,
fake_5575180433264999,
fake_9876938708169847,
fake_8634549414351658,
fake_938271301212894
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3660781155115522,
fake_12992420863492016,
fake_4242569475835569,
fake_5701419047798999,
fake_5033211610928006
result, different session:
fake_3660781155115522,
fake_12992420863492016,
fake_4242569475835569,
fake_5701419047798999,
fake_5033211610928006
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3942560852393462,
fake_5274250761054557,
fake_939401108941267,
fake_6304388276038109,
fake_496283027674842
result, different session:
fake_3942560852393462,
fake_5274250761054557,
fake_939401108941267,
fake_6304388276038109,
fake_496283027674842
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_1858619812877289,
fake_8414830562713584,
fake_5373127056319169,
fake_05109101724808074,
fake_31008943602340233
result, different session:
fake_1858619812877289,
fake_8414830562713584,
fake_5373127056319169,
fake_05109101724808074,
fake_31008943602340233
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_7146720320452604,
fake_8736776310785113,
fake_05808116539250796,
fake_4072016497872193,
fake_9432015870562929
result, different session:
fake_7146720320452604,
fake_8736776310785113,
fake_05808116539250796,
fake_4072016497872193,
fake_9432015870562929
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3436919621795842,
fake_722704752723129,
fake_3990004318384295,
fake_19309788720467402,
fake_49311635186073177
result, different session:
fake_48592702595632553,
fake_8507668378873599,
fake_308380124321304,
fake_8138809552350719,
fake_012422560965752227
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_5715362054581736,
fake_9745573955152791,
fake_6928431968134712,
fake_04991620663422225,
fake_33929661750594287
result, different session:
fake_5715362054581736,
fake_9745573955152791,
fake_6928431968134712,
fake_04991620663422225,
fake_33929661750594287
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3581128841627881,
fake_579101952840454,
fake_15893828783634834,
fake_6307426457970329,
fake_796161698457214
result, different session:
fake_3581128841627881,
fake_579101952840454,
fake_15893828783634834,
fake_6307426457970329,
fake_796161698457214
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_5168440405623642,
fake_13254652791538812,
fake_004556596189603246,
fake_6554395455657989,
fake_25532034382336666
result, different session:
fake_5168440405623642,
fake_13254652791538812,
fake_004556596189603246,
fake_6554395455657989,
fake_25532034382336666
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_5143628727050273,
fake_33310420880310243,
fake_13402692053981125,
fake_7674178642074407,
fake_3452272441936428
result, different session:
fake_6646550163590736,
fake_8371594510782927,
fake_22565469375254454,
fake_941851889766377,
fake_22175474605946954
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 2, 2, 2, 2, 2
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 2, 2, 2, 2, 2
result, different session: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
ab578407-370d-4f49-b646-146a5387984b_1p,
1a009336-8fc6-4c29-9156-8b7703d81ecb_1p,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_1p,
aaafbb05-7196-4933-bb52-b72db6df608a_1p,
d0134525-2c97-46f5-a372-2e6c225c3019_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p,
ee2fce28-59db-4014-a550-5b43f289183d_1p,
f882e270-5804-4f67-be63-599dba30cc12_1p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p
result, different session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p,
ee2fce28-59db-4014-a550-5b43f289183d_1p,
f882e270-5804-4f67-be63-599dba30cc12_1p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
aeb5290e-1534-4281-92c9-893e65c28627_1p,
528a685d-63c8-4a8c-88ec-037d368af791_1p,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p
result, different session:
aeb5290e-1534-4281-92c9-893e65c28627_1p,
528a685d-63c8-4a8c-88ec-037d368af791_1p,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p,
81902166-5563-4879-b345-eb7a086625ea_1p,
8f539dfe-0634-42b6-8409-acef00b99289_1p,
679ab034-ba16-4437-935c-e64f06433be9_1p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p
result, different session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p,
81902166-5563-4879-b345-eb7a086625ea_1p,
8f539dfe-0634-42b6-8409-acef00b99289_1p,
679ab034-ba16-4437-935c-e64f06433be9_1p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_1p,
6d3e0086-b2ae-468d-b231-683355928a4d_1p,
28ad0d17-5e84-40ee-af86-a5c9175e415d_1p,
1c564983-4c6a-4bea-be2a-dcccb8295bef_1p,
638188b4-c2fc-4133-8b65-797114180f04_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_1p,
ffeb2f66-c77b-474f-a305-a04f4afc87af_1p,
b2954dd3-3942-497b-9059-edc1f51db921_1p,
294cc579-3da1-4084-9f1f-59c61c553cf9_1p,
02e3522b-e907-4849-98dd-593d197989e0_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_1p,
9194ae03-b335-40f3-af6f-718e7be9c8ae_1p,
f1c5e294-1695-4474-9704-2d549880ce28_1p,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_1p,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
df92863b-7453-462d-8fab-f15094cfe5af_1p,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_1p,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_1p,
c8baedb9-0082-4eec-9aca-059c23d731c5_1p,
73afc3df-3d35-4c5c-8056-96142486ae81_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_1p,
fdbdfe87-3692-40b7-bc31-76b969b98541_1p,
f84e10ce-2813-440f-bda8-0a17d63d0c90_1p,
c602aba9-2920-4010-a515-bd9d1c8539d8_1p,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_1p,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p,
52d604c6-2ce9-4838-934f-3e90c4bcda12_1p,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_1p,
76391515-fb72-4c62-a581-0a8c545f276b_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
ab578407-370d-4f49-b646-146a5387984b_1p,
1a009336-8fc6-4c29-9156-8b7703d81ecb_1p,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_1p,
aaafbb05-7196-4933-bb52-b72db6df608a_1p,
d0134525-2c97-46f5-a372-2e6c225c3019_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p,
ee2fce28-59db-4014-a550-5b43f289183d_1p,
f882e270-5804-4f67-be63-599dba30cc12_1p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p
result, different session:
bc961a97-730f-4b98-9434-da4795a8b0f1_1p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_1p,
ee2fce28-59db-4014-a550-5b43f289183d_1p,
f882e270-5804-4f67-be63-599dba30cc12_1p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
aeb5290e-1534-4281-92c9-893e65c28627_1p,
528a685d-63c8-4a8c-88ec-037d368af791_1p,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p
result, different session:
aeb5290e-1534-4281-92c9-893e65c28627_1p,
528a685d-63c8-4a8c-88ec-037d368af791_1p,
30d559cc-0031-4a5b-a870-4f11b6a100a0_1p,
b2c792f8-1b1a-493f-8388-fe17cfc99931_1p,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p,
81902166-5563-4879-b345-eb7a086625ea_1p,
8f539dfe-0634-42b6-8409-acef00b99289_1p,
679ab034-ba16-4437-935c-e64f06433be9_1p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p
result, different session:
46ab308c-e44d-4c84-9b89-8630607096f9_1p,
81902166-5563-4879-b345-eb7a086625ea_1p,
8f539dfe-0634-42b6-8409-acef00b99289_1p,
679ab034-ba16-4437-935c-e64f06433be9_1p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_1p,
6d3e0086-b2ae-468d-b231-683355928a4d_1p,
28ad0d17-5e84-40ee-af86-a5c9175e415d_1p,
1c564983-4c6a-4bea-be2a-dcccb8295bef_1p,
638188b4-c2fc-4133-8b65-797114180f04_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_1p,
ffeb2f66-c77b-474f-a305-a04f4afc87af_1p,
b2954dd3-3942-497b-9059-edc1f51db921_1p,
294cc579-3da1-4084-9f1f-59c61c553cf9_1p,
02e3522b-e907-4849-98dd-593d197989e0_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_1p,
9194ae03-b335-40f3-af6f-718e7be9c8ae_1p,
f1c5e294-1695-4474-9704-2d549880ce28_1p,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_1p,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
df92863b-7453-462d-8fab-f15094cfe5af_1p,
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_1p,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_1p,
c8baedb9-0082-4eec-9aca-059c23d731c5_1p,
73afc3df-3d35-4c5c-8056-96142486ae81_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_1p,
fdbdfe87-3692-40b7-bc31-76b969b98541_1p,
f84e10ce-2813-440f-bda8-0a17d63d0c90_1p,
c602aba9-2920-4010-a515-bd9d1c8539d8_1p,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_1p,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_1p,
52d604c6-2ce9-4838-934f-3e90c4bcda12_1p,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_1p,
76391515-fb72-4c62-a581-0a8c545f276b_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
script cache
Caching of scripts in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Cross-session third-party tracking testsWhich browsers prevent third-party trackers from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow third-party trackers to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
ab578407-370d-4f49-b646-146a5387984b_3p,
1a009336-8fc6-4c29-9156-8b7703d81ecb_3p,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_3p,
aaafbb05-7196-4933-bb52-b72db6df608a_3p,
d0134525-2c97-46f5-a372-2e6c225c3019_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_3p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_3p,
ee2fce28-59db-4014-a550-5b43f289183d_3p,
f882e270-5804-4f67-be63-599dba30cc12_3p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p
result, different session:
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p,
c846cb44-12d2-41b3-b2a6-38ca1a4518ed_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_3p,
81902166-5563-4879-b345-eb7a086625ea_3p,
8f539dfe-0634-42b6-8409-acef00b99289_3p,
679ab034-ba16-4437-935c-e64f06433be9_3p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_3p,
6d3e0086-b2ae-468d-b231-683355928a4d_3p,
28ad0d17-5e84-40ee-af86-a5c9175e415d_3p,
1c564983-4c6a-4bea-be2a-dcccb8295bef_3p,
638188b4-c2fc-4133-8b65-797114180f04_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_3p,
9194ae03-b335-40f3-af6f-718e7be9c8ae_3p,
f1c5e294-1695-4474-9704-2d549880ce28_3p,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_3p,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_3p,
91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_3p,
c8baedb9-0082-4eec-9aca-059c23d731c5_3p,
73afc3df-3d35-4c5c-8056-96142486ae81_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_3p,
fdbdfe87-3692-40b7-bc31-76b969b98541_3p,
f84e10ce-2813-440f-bda8-0a17d63d0c90_3p,
c602aba9-2920-4010-a515-bd9d1c8539d8_3p,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_3p,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_3p,
52d604c6-2ce9-4838-934f-3e90c4bcda12_3p,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_3p,
76391515-fb72-4c62-a581-0a8c545f276b_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_6197750246799332,
fake_7493224717173224,
fake_39690080878812295,
fake_3499302914876783,
fake_6376099017152208
result, different session:
fake_6197750246799332,
fake_7493224717173224,
fake_39690080878812295,
fake_3499302914876783,
fake_6376099017152208
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_8459815888397944,
fake_6322265984597493,
fake_09055315168966094,
fake_48241871461750896,
fake_19993217590295775
result, different session:
fake_8459815888397944,
fake_6322265984597493,
fake_09055315168966094,
fake_48241871461750896,
fake_19993217590295775
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_0948578769211601,
fake_2854228076073999,
fake_9265517333925468,
fake_7568815368413837,
fake_2876874309361317
result, different session:
fake_0948578769211601,
fake_2854228076073999,
fake_9265517333925468,
fake_7568815368413837,
fake_2876874309361317
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_792273987993489,
fake_9184511528284913,
fake_2660063938862911,
fake_9197925666775417,
fake_38737757938956574
result, different session:
fake_792273987993489,
fake_9184511528284913,
fake_2660063938862911,
fake_9197925666775417,
fake_38737757938956574
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_09895228659586008,
fake_6192312077915223,
fake_6647081292400963,
fake_5126908318592047,
fake_5306748032910467
result, different session:
fake_09895228659586008,
fake_6192312077915223,
fake_6647081292400963,
fake_5126908318592047,
fake_5306748032910467
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_11128483167182512,
fake_535925231151301,
fake_35694103762681073,
fake_549161632597974,
fake_7828872582445763
result, different session:
fake_49129262113345606,
fake_8763345258305821,
fake_8224548025916925,
fake_6718312604470744,
fake_5140525353185299
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_010642839346747257,
fake_8556111773620505,
fake_022109047826261108,
fake_07475326890063694,
fake_0688721200965301
result, different session:
fake_010642839346747257,
fake_8556111773620505,
fake_022109047826261108,
fake_07475326890063694,
fake_0688721200965301
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_23476179971009103,
fake_8829897398962219,
fake_1556339292549127,
fake_5316202696245025,
fake_7070792652376605
result, different session:
fake_23476179971009103,
fake_8829897398962219,
fake_1556339292549127,
fake_5316202696245025,
fake_7070792652376605
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_09696218067491036,
fake_8302695643015641,
fake_7504670805823608,
fake_3602932056316026,
fake_41237752993550614
result, different session:
fake_09696218067491036,
fake_8302695643015641,
fake_7504670805823608,
fake_3602932056316026,
fake_41237752993550614
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_855061683402975,
fake_005183482725160671,
fake_7892878654952777,
fake_09958558834898978,
fake_4914196552905674
result, different session:
fake_2919120881469379,
fake_9565964494655534,
fake_8726650733294565,
fake_7451107966279966,
fake_7642062781640866
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 2, 2, 2, 2, 2
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 2, 2, 2, 2, 2
result, different session: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
ab578407-370d-4f49-b646-146a5387984b_3p,
1a009336-8fc6-4c29-9156-8b7703d81ecb_3p,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_3p,
aaafbb05-7196-4933-bb52-b72db6df608a_3p,
d0134525-2c97-46f5-a372-2e6c225c3019_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_3p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_3p,
ee2fce28-59db-4014-a550-5b43f289183d_3p,
f882e270-5804-4f67-be63-599dba30cc12_3p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
aeb5290e-1534-4281-92c9-893e65c28627_3p,
528a685d-63c8-4a8c-88ec-037d368af791_3p,
30d559cc-0031-4a5b-a870-4f11b6a100a0_3p,
b2c792f8-1b1a-493f-8388-fe17cfc99931_3p,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_3p,
81902166-5563-4879-b345-eb7a086625ea_3p,
8f539dfe-0634-42b6-8409-acef00b99289_3p,
679ab034-ba16-4437-935c-e64f06433be9_3p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_3p,
6d3e0086-b2ae-468d-b231-683355928a4d_3p,
28ad0d17-5e84-40ee-af86-a5c9175e415d_3p,
1c564983-4c6a-4bea-be2a-dcccb8295bef_3p,
638188b4-c2fc-4133-8b65-797114180f04_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_3p,
ffeb2f66-c77b-474f-a305-a04f4afc87af_3p,
b2954dd3-3942-497b-9059-edc1f51db921_3p,
294cc579-3da1-4084-9f1f-59c61c553cf9_3p,
02e3522b-e907-4849-98dd-593d197989e0_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_3p,
9194ae03-b335-40f3-af6f-718e7be9c8ae_3p,
f1c5e294-1695-4474-9704-2d549880ce28_3p,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_3p,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session: , 2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_3p, 91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_3p, c8baedb9-0082-4eec-9aca-059c23d731c5_3p, 73afc3df-3d35-4c5c-8056-96142486ae81_3p
result, different session: undefined
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_3p,
fdbdfe87-3692-40b7-bc31-76b969b98541_3p,
f84e10ce-2813-440f-bda8-0a17d63d0c90_3p,
c602aba9-2920-4010-a515-bd9d1c8539d8_3p,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_3p,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_3p,
52d604c6-2ce9-4838-934f-3e90c4bcda12_3p,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_3p,
76391515-fb72-4c62-a581-0a8c545f276b_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
ab578407-370d-4f49-b646-146a5387984b_3p,
1a009336-8fc6-4c29-9156-8b7703d81ecb_3p,
9ffac5bb-9da0-47c4-b155-fdfcafab4e9d_3p,
aaafbb05-7196-4933-bb52-b72db6df608a_3p,
d0134525-2c97-46f5-a372-2e6c225c3019_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
bc961a97-730f-4b98-9434-da4795a8b0f1_3p,
a7f946cf-faa8-4c53-becc-c6519f6bba4f_3p,
ee2fce28-59db-4014-a550-5b43f289183d_3p,
f882e270-5804-4f67-be63-599dba30cc12_3p,
8bb057b5-ccc8-478a-8d42-5651ab499e89_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
aeb5290e-1534-4281-92c9-893e65c28627_3p,
528a685d-63c8-4a8c-88ec-037d368af791_3p,
30d559cc-0031-4a5b-a870-4f11b6a100a0_3p,
b2c792f8-1b1a-493f-8388-fe17cfc99931_3p,
3ffb6ed0-4892-40c0-8471-5be4cd2a8f7b_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
46ab308c-e44d-4c84-9b89-8630607096f9_3p,
81902166-5563-4879-b345-eb7a086625ea_3p,
8f539dfe-0634-42b6-8409-acef00b99289_3p,
679ab034-ba16-4437-935c-e64f06433be9_3p,
7c39ebbf-bd54-4764-a1ee-adfcbbf2a4fb_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
62bd2dbc-8547-43c4-8387-ef38495a10ff_3p,
6d3e0086-b2ae-468d-b231-683355928a4d_3p,
28ad0d17-5e84-40ee-af86-a5c9175e415d_3p,
1c564983-4c6a-4bea-be2a-dcccb8295bef_3p,
638188b4-c2fc-4133-8b65-797114180f04_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
18670d8e-7445-4b90-b5b9-a6fc14ac99c2_3p,
ffeb2f66-c77b-474f-a305-a04f4afc87af_3p,
b2954dd3-3942-497b-9059-edc1f51db921_3p,
294cc579-3da1-4084-9f1f-59c61c553cf9_3p,
02e3522b-e907-4849-98dd-593d197989e0_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
83fe9d03-30ee-4948-a9bc-5218672c2c36_3p,
9194ae03-b335-40f3-af6f-718e7be9c8ae_3p,
f1c5e294-1695-4474-9704-2d549880ce28_3p,
1e2b7240-1a2b-4a43-ad0c-8d84a4cd84c0_3p,
e0a5ca1a-9191-45e9-933b-b7e7101632e6_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session: , 2bdcb7d1-5867-4ecc-bd72-5d4ce02353c5_3p, 91c23d76-0123-4dfa-b1ee-9d9ea8f19d8e_3p, c8baedb9-0082-4eec-9aca-059c23d731c5_3p, 73afc3df-3d35-4c5c-8056-96142486ae81_3p
result, different session: , , , ,
unsupported: true, false, false, false, false
passed: , true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0091eaa4-d94b-4aae-890d-20215c2fb159_3p,
fdbdfe87-3692-40b7-bc31-76b969b98541_3p,
f84e10ce-2813-440f-bda8-0a17d63d0c90_3p,
c602aba9-2920-4010-a515-bd9d1c8539d8_3p,
23ae349e-b48f-4fb7-afbf-4f7ea763b7c1_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
9226d658-d9dc-43e4-b613-949c8e04ec0b_3p,
bf58860c-17d5-42df-b2cb-8eb3c2b042a4_3p,
52d604c6-2ce9-4838-934f-3e90c4bcda12_3p,
fdfe4f16-304a-4cb6-81a3-a7e55edf2817_3p,
76391515-fb72-4c62-a581-0a8c545f276b_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
script cache
Caching of scripts in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false