Nightly Builds

(default settings)
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brave
1.77
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chrome
135.0
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duckduckgo
1.127
edge logo
edge
135.0
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firefox
137.0a1
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opera
118.0
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safari
18.2
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tor
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vivaldi
7.2
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.
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 first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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 first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: h2, h2, h2, h2
unsupported: true, true, true, true
passed: undefined
test failed: 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 first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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 first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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 first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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 first party:
Error: Unsupported,
h3,
h3,
Error: Unsupported
result, different first party: h2, h2, h2, h2
unsupported: true, false, false, true
passed: , true, true
test failed: 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
result, different first party: h2, h2, h2, h2
unsupported: true, true, true, true
passed: undefined
test failed: 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 first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party:
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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 first party:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
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')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party:
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
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')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_http,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_http,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_http,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_http
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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 first party:
0924fe4a-d12e-4351-8776-0578cfc20dba_http,
3c23ace0-158e-452e-bd97-8e1b2e653552_http,
9ac4ca03-961e-43fc-9d79-14910801fe63_http,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_http
result, different first party:
0924fe4a-d12e-4351-8776-0578cfc20dba_http,
3c23ace0-158e-452e-bd97-8e1b2e653552_http,
9ac4ca03-961e-43fc-9d79-14910801fe63_http,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
4604fca6-7d8f-4577-bd1b-a621e735382e_http,
26908635-2334-4e48-931b-f5d48df5803b_http,
67988fb5-2e66-422c-8f7b-ef888011c2af_http,
8730beff-ff90-4dcd-8a0d-2beb31a52758_http
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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 first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f_http,
9c32f38b-eaf8-43c2-984a-1651d0915a05_http,
d081ea16-47e7-45ff-917f-28932d814377_http,
7131a853-b4e8-4015-9d30-8f7458942210_http
result, different first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f_http,
9c32f38b-eaf8-43c2-984a-1651d0915a05_http,
d081ea16-47e7-45ff-917f-28932d814377_http,
7131a853-b4e8-4015-9d30-8f7458942210_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
7b84532e-f084-44e3-aa09-ae363cdf0d98_http,
f2a168b9-8331-4566-9610-e21bb2e22f49_http,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_http,
3fff33a4-7253-453a-984b-da801d2908c7_http
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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 first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_http,
2c6db9eb-51b1-4d20-a720-4683792abdd8_http,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_http,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_http
result, different first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_http,
2c6db9eb-51b1-4d20-a720-4683792abdd8_http,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_http,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
e562b156-0446-4843-b127-bdb747121163_http,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_http,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_http,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_http
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_http,
d98cf9ec-ee64-41cf-b856-434139cd9692_http,
834e1991-6732-4c97-96a7-3e96c7c393f8_http,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_http
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_http,
c42e2e78-39cf-4511-988d-2adcabe85a3a_http,
4cb85808-a298-427e-a095-2112f89a0ebe_http,
7c6616f8-ff31-44a0-a933-a053ccfd8281_http
result, different first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_http,
c42e2e78-39cf-4511-988d-2adcabe85a3a_http,
4cb85808-a298-427e-a095-2112f89a0ebe_http,
7c6616f8-ff31-44a0-a933-a053ccfd8281_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_js,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_js,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_js,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_js
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
0924fe4a-d12e-4351-8776-0578cfc20dba_js,
3c23ace0-158e-452e-bd97-8e1b2e653552_js,
9ac4ca03-961e-43fc-9d79-14910801fe63_js,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_js
result, different first party:
0924fe4a-d12e-4351-8776-0578cfc20dba_js,
3c23ace0-158e-452e-bd97-8e1b2e653552_js,
9ac4ca03-961e-43fc-9d79-14910801fe63_js,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
4604fca6-7d8f-4577-bd1b-a621e735382e_js,
26908635-2334-4e48-931b-f5d48df5803b_js,
67988fb5-2e66-422c-8f7b-ef888011c2af_js,
8730beff-ff90-4dcd-8a0d-2beb31a52758_js
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f_js,
9c32f38b-eaf8-43c2-984a-1651d0915a05_js,
d081ea16-47e7-45ff-917f-28932d814377_js,
7131a853-b4e8-4015-9d30-8f7458942210_js
result, different first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f_js,
9c32f38b-eaf8-43c2-984a-1651d0915a05_js,
d081ea16-47e7-45ff-917f-28932d814377_js,
7131a853-b4e8-4015-9d30-8f7458942210_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
7b84532e-f084-44e3-aa09-ae363cdf0d98_js,
f2a168b9-8331-4566-9610-e21bb2e22f49_js,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_js,
3fff33a4-7253-453a-984b-da801d2908c7_js
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_js,
2c6db9eb-51b1-4d20-a720-4683792abdd8_js,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_js,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_js
result, different first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_js,
2c6db9eb-51b1-4d20-a720-4683792abdd8_js,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_js,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
e562b156-0446-4843-b127-bdb747121163_js,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_js,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_js,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_js
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_js,
d98cf9ec-ee64-41cf-b856-434139cd9692_js,
834e1991-6732-4c97-96a7-3e96c7c393f8_js,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_js
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_js,
c42e2e78-39cf-4511-988d-2adcabe85a3a_js,
4cb85808-a298-427e-a095-2112f89a0ebe_js,
7c6616f8-ff31-44a0-a933-a053ccfd8281_js
result, different first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_js,
c42e2e78-39cf-4511-988d-2adcabe85a3a_js,
4cb85808-a298-427e-a095-2112f89a0ebe_js,
7c6616f8-ff31-44a0-a933-a053ccfd8281_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
Passed
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_779180321700703,
fake_7623901727851621,
fake_33035264360182803,
fake_8557662558423638
result, different first party:
fake_9783003439284208,
fake_6443616671240253,
fake_8257839830780487,
fake_2744307497624554
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_750612884655492,
fake_4514638643266733,
fake_6224509922134003,
fake_832611967190912
result, different first party:
fake_8594402357279702,
fake_5616757008218292,
fake_28324860079815384,
fake_2232070732218261
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_4488048450283981,
fake_3802923999325465,
fake_14087616555706184,
fake_8917814523390251
result, different first party:
fake_8917524754774699,
fake_2363097923175752,
fake_4620437833038875,
fake_7455591969833273
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_2534506205532836,
fake_9914072188539294,
fake_4706233565861233,
fake_8057852057442552
result, different first party:
fake_6539316368583943,
fake_26825058748077435,
fake_07537347610351519,
fake_1956550585436001
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_8397709390577062,
fake_3263313455987369,
fake_2693906776915511,
fake_8036138708039617
result, different first party:
fake_06142087632384374,
fake_40043485206658613,
fake_22053748399141848,
fake_2512631737695523
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_5757572671840001,
fake_039489055509354776,
fake_8764343022900356,
fake_7104798175931994
result, different first party:
fake_19187279551629643,
fake_10934808144816821,
fake_6726220461177719,
fake_3984026576254869
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_2803440083232758,
fake_18125968886432586,
fake_4964412784812142,
fake_07804810041746024
result, different first party:
fake_9949962151422411,
fake_5838543807307599,
fake_6014651733710057,
fake_31156612675298434
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_8557443629542938,
fake_19251053191245937,
fake_5239947482864418,
fake_6986297640892258
result, different first party:
fake_11518988471317981,
fake_4018570646792119,
fake_6190824730366165,
fake_26171287170344426
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_7462911104670205,
fake_561819675474172,
fake_6180798793288558,
fake_2575028402916828
result, different first party:
fake_3140016008148745,
fake_8550502517987053,
fake_08708536344478146,
fake_3129744586314014
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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.
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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 2, 2, 2, 2
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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.
Passed
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Passed
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Passed
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
H2 connection
HTTP/2 is a web connection protocol introduced in 2015. Some browsers re-use HTTP/2 connections across websites and can thus be used to track users.
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${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:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${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:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
74a38dd7d7666e4061c1e82eaf882d19,
0c8e93e9e6f6cec53a06ee4ab822cd37,
12c7118c93536dc37bacc5f7578bfef7,
3b67f20d32b712a1ed6e465eb9ee95eb
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
c625b043e8b4ade082753f89d3cdae8a,
cf16a07370fb2affcb4a17910e1483ae,
2bcf1691e84d203f0bcdcddab9a9aa12,
8e0101d932339b3564a161d66afd74ab
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
55a35ebd30a7eeab71bd7e7db6397287,
447b9635bd459d21c4be7aa5838b31c6,
056a28c9f49b31a9baa45efeecaa020f,
dd22c171fa10ce7479e16b39bdb5da3f
result, different first party:
e107a5aeb5802463a1d6924b5d1ae3f3,
77ca1ad3c98f402a954b44a565d8c81e,
9c142fea26f1968a940590cb686e6042,
12c74a981057091fd3f178d0383a9fcb
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
9ae9a145231e94a9320db80a20c348fd,
e1e18d8ed8d580eff4572a67581df2e2,
bed04dfae6057827d38a0e6e04a57e73,
9aa361c3653c724a909e91abae89a8d8
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
5fc27a97af1b384655e6b62b2aa58d67,
e0b8e3d347da39ce863ce82e0b5afb3a,
45a353c5d2b7a0650edc056ee308b6d5,
4ef5d865f6a9d787842c87e4a75f657f
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
bd139472918581d8386dc9e79e8aea8c,
a3fc70088b528fcdf4415757500d3f9b,
b32ab921058cd7409093c43d7385c356,
47c0ad0d7882f4d4928db5d911e37f5c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: , 0450cf43b1ba7a283024ae12dd270d37, 0a8a51398c34d75356a016fd3b96c20c, 8be342a1f09d48b63a1486b11687bcd9
result, different first party: , , ,
unsupported: true, false, false, false
passed: , true, true, true
test failed: 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
passed: undefined
test failed: 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:
b68fd040c55d22c7db81b22c4f3f85c7,
a1e1e002421992cd1758996f3e6f6dd4,
41f88b13f4dd86da9b6b277cb7ae2766,
33c186022de7e874d993d5ba15b17db6
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: null
read: null
result, same first party: , , ,
result, different first party:
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , ,
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: Used http, Used http, Used http, Used http
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: null
read: null
result, same first party: , , ,
result, different first party:
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , ,
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
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')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party:
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
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')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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.
Passed
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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Passed
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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Passed
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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 3, 3, 3, 3
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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:
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , ,
result, different first party: , Error: ServiceWorker registration failed, Error: ServiceWorker registration failed,
unsupported: false, false, false, false
passed: undefined
test failed: true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${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:
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , ,
result, different first party: , , ,
unsupported: false, false, false, false
passed: undefined
test failed: true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${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:
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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=${key}`);
    }
read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }
result, same first party: , , ,
result, different first party: , , ,
unsupported: false, false, false, false
passed: undefined
test failed: true, true, true, true
Unsupported
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${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:
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined
result, different first party:
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
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:
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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.
Passed
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party:
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
f1973d39cdf35eb646048969293996daaaf08ac1f83f3f80a5fd392b16ae43b6,
fa8ee10c099c73de7ba5cefef3e94fa0f2b0f3bf7b0ca437ef3044ec57623d04,
6c600f173d7b959105d154c548443e243c9e99de9a97082877a1f3258cf17e8a,
384ab4f1836c2724f9d28e369f3ee4193b0608ce7f6d60f0100ec54706d85b0b
result, different first party:
26f68b79a4cfff73c5c8b953d6317654b36c2df4c84c7380ba4956523b6d4a30,
916383aaeea2764d6dd677743ba8f1223f039597daeb157261cb52618db9f77b,
e546d073e6dcf005b35046ff83badcfeda148d3ff0525b50851346cfece4db44,
148dc23dbed70a22d05fae9e9089be5f82db1aeaa519192104f5d7a423b8cf66
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
dc9b9178b26f4af57105679697fe5be4a1984f7f67a2a283667459e0315be8df,
a687838e0b8ff49edcc7ceb37a292842ef2ff5884c28a91764c1dac9d752ce56,
f8407ba2470a595c7d9aff3e1b9ba7069da5c9c3f8bfd56433ea8430632f60ca,
a731841a6e18c4409b4369a47eecbd5e003da2894732fc4d64cb8b5fc408d834
result, different first party:
d65442423b6a50fc7ca2dde53354b6b0b9b002dc04abc7b95550869a8e223f51,
857fa00ba506d2adfbd08fb4b2ec8e79c9adacb2505f248f28433a4bcd852061,
ad8897320b53802a8330fefb07dcab57773b328ff3b8f226f301aa659a166785,
33703d7215ceff86b6602567cb1fc67d455c83c2fe416588a1472b78e1491c50
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
2d55d38a7779adc1eba9607da35dff8066189dc6ab1930f1448fcf69de43a696,
d428fac98752f8e4f03f3dcd5e042a3a0d46f8a470e19662fe4a6bc7db205147,
9ceaed11e1518d6f51c1d1fa87a9de91bed7b813d14a7cc6a13162cd050dcd41,
cadc05b0bc942dfe5cf8be97006cdfe6a3cb136412f8aa72d99d80f7b1b233ea
result, different first party:
05827852c494fc8ce7623ed8050a880aac558e27bb224992a9457aafad38c045,
7eaa78b33ffdf816af953c6a5956d4041445fec6ef8f84a9673020615d78cf28,
bf80a9bf90eedeac679832956991dd5eb2c6a2b871d79d7d897a6956fa4bdfa6,
7fde42a5663f8a1bbc7572d4c5ccb172e68696cb0fa2d763ce641c3979ca3c97
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
62291d3762710590b29f4a9c7190e4ff1b247829493108469dd9ddfec9e8d1ce,
993f4260bfa7415ea60e7bde8c0fe4ddb3ee9220eca131e73a78d69cebb93fa4,
b0055c35011f0ebd5a5568e28ea9039437a9c079a5d140886111e3a9a3b37d24,
376d920a9fab2727e7b9f18de7800dd9ae2f4ffb9ce180fdf9e92f19776be252
result, different first party:
db1a419deb34d797f83c76b44196056394cb0bd6cf144aff818dec8ee412cd5d,
77f8aeec35854025a057b3f7c53f1b4b227b7736fffbd50c7bbffe7f5e7c1496,
5ff5c298495531ac7ebbd24f7eb553972e9a6ab103c0dd6b1120f2415771c74e,
4de21cb6edc7d2480b5002a86eaf841f62ce7c7ce7c85a61a491c95e600c0391
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
44707d421034ad8f4beda4f0b6488de0daeaa93c07cd35e5782533ed70049219,
57b1fe06436e02497dec313ae1590c497f1d4658fef83c828c6a610496273388,
06c981bbeff7a760f862fe319266f3144ed49edeaa8b5b360254b4ab0655707e,
7ec7ece395bbec729bbffed131c2c026ebf24851f2be0a0be655f13fb3b7d447
result, different first party:
bbce06f79207570b99b28a2b5891fff8ddd581f1c168b3e9e78f74ccc869ff8a,
9e359b396504b1e9d8b180c411817fa52248a907cc526538716b335145bb12ad,
93fe3dab8963910e3d9f3acea72d75768e1ae10098c7bfed62d4e80bb5e0e451,
3e780c81f26e3f19dc08e8d1e0ae102c46c74e3652132b7eeb68f8e25602df29
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
f56cbebd5baa462290599e778aaedc6b2d5637f8d96075b852e70d6e50842148,
6ce47b6136c3e698bd8decf1ea20473ca1dd46935cac732584e06ccb0552455c,
c50d9207833c86fbe7962c14e4ec6f713b911fbc91bc7e87026c187fc6a1f5c1,
bb85398bc8fcf4f6269c3fd6710fcbb105fa4a74a60293b9bb9aaee31d749722
result, different first party:
bdcfc5c5dc4a018fa097389f2e08d11d506a0a2df7816452725b7904e794785a,
0adfb14f66c3c5c464abf823b51d960f3ccf93c8796e31651d3495e6069f9e40,
0de9ede9f1b8625605d50456c35fef5f7ed9b360353b1bbbfaeb9018dfacfef1,
ef525bf9443341e8c97c9d75307dc96b13018f76bda899ae9b32d41a9db1062d
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
fca3bd01d4aeb19f64b884bdb2f5114b59a247b86b61347d53aa2afd34f6f085,
54bbec34bde4b42bfcd55be25bf449c255ad70c854da31076b7af053864ae9a7,
e6ede161c947d132e40b62f21bb3faee71f8711390c4d2eeba2ba56f87cdda18,
6227e6913386702ee0b0cc5b4500129304ee6859683566637ae74f787e43b074
result, different first party:
bbbe76242eef4f4d7128b4d89e74ff8421baed8d063b17992860f40a7e5f16ee,
97e84f40850001e7ac998c347c752260e73a9c5e09026a6de6932d853139c120,
ce0feeff2d2de48d6a832d9d3166e0f87efb7da5af804880e48bebb9749bfc40,
6388e51eee8b8781c4c4c0d62418e75df9f223b8074b35bf5163ddd02cbf72d6
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
47fc9f7fc7cd6586ebcb8d26ce616fc0f66309ae327e53b08159ad37e3da09c7,
c2e6aacb32f06a33340fd49a7a41c7c95dd3ac89b1d4acb4afba660ae1e12526,
c5b02e8edab8d52bd3f7350cf225fcdc044103614a06f8bb87e746f39edcf904,
7098ab0d57665b948c1ee3a527ac6f3b448e2a9bd70fc36ab1edaba0791b79f4
result, different first party:
0c2b702239e1473331633ea341ae84b34be5801526f38dc6a94021f275bd7ec2,
b5ab8411cb2fa9e199ecba1b90b32fecb9fb26a5296285bd854bf8ef6746a18f,
61b9c83c816635dabda3d6babc8da08a51f0a2588338686614772443fa0e3bf0,
b4badf8553a599cf28c9a0f8512a97abd0014311c4d46be8066096b0f59ba789
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
fcd18be2c967f4418a98eb63eb7c5255ee9282d4d411df78a6a5d5d22a8da5eb,
8aac51188668c328c10f91e16f867738a429fc1dff3033084d8b411e7aa4cb04,
c49b06ec478bcedb738c2570d1d59d8d79852e23328c8db9aa6dd3a1bb6068a7,
c655efa72c4f3ee60a8a517ddc29fd98df95241817fd7f1326364c26fe4ed545
result, different first party:
d7313079be357950dd952c2bb11738ace7fae77dd9cda9f082c7feea4e673b5d,
e8ed0883234a6c4ad9024279983921b7dfd2fc499da99ac913905882be9eccf0,
ffd583b8f47fda315f81c8b0376940879dcff80a7a967d4fdf1857977357b5c3,
c52e58c1c347b1fba8de209feb93b62808f960d8926848a361c1298adfa6fc4c
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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/
result, different first party:
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
passed: false, false, false, false
test failed: 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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78,
abb4921b-1ec6-4a31-aa47-9b6bc2693982,
ad61cd3b-7f21-44f8-bc0f-9399664c267e,
ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
0924fe4a-d12e-4351-8776-0578cfc20dba,
3c23ace0-158e-452e-bd97-8e1b2e653552,
9ac4ca03-961e-43fc-9d79-14910801fe63,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
4604fca6-7d8f-4577-bd1b-a621e735382e,
26908635-2334-4e48-931b-f5d48df5803b,
67988fb5-2e66-422c-8f7b-ef888011c2af,
8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
33bd1316-4999-46d3-85e5-9ddaca53a69f,
9c32f38b-eaf8-43c2-984a-1651d0915a05,
d081ea16-47e7-45ff-917f-28932d814377,
7131a853-b4e8-4015-9d30-8f7458942210
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
7b84532e-f084-44e3-aa09-ae363cdf0d98,
f2a168b9-8331-4566-9610-e21bb2e22f49,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
58d7ea3d-bc86-4d56-b321-b24cad217a6a,
2c6db9eb-51b1-4d20-a720-4683792abdd8,
c4ff6353-1aa5-4268-aad6-89d84a93ecea,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
e562b156-0446-4843-b127-bdb747121163,
bf90e98b-1dc5-4d38-8681-b79735bbd28e,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
d98cf9ec-ee64-41cf-b856-434139cd9692,
834e1991-6732-4c97-96a7-3e96c7c393f8,
728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
c42e2e78-39cf-4511-988d-2adcabe85a3a,
4cb85808-a298-427e-a095-2112f89a0ebe,
7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_6ed9ecc6-966f-4b36-91e6-7119813d3d78,
name_abb4921b-1ec6-4a31-aa47-9b6bc2693982,
name_ad61cd3b-7f21-44f8-bc0f-9399664c267e,
name_ae71b7e5-0054-4b93-b9ba-b54f65690acc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_0924fe4a-d12e-4351-8776-0578cfc20dba,
name_3c23ace0-158e-452e-bd97-8e1b2e653552,
name_9ac4ca03-961e-43fc-9d79-14910801fe63,
name_f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
result, different first party:
name_0924fe4a-d12e-4351-8776-0578cfc20dba,
name_3c23ace0-158e-452e-bd97-8e1b2e653552,
name_9ac4ca03-961e-43fc-9d79-14910801fe63,
name_f856f5fe-f8d2-4a28-bf0c-8a2002d46f50
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_4604fca6-7d8f-4577-bd1b-a621e735382e,
name_26908635-2334-4e48-931b-f5d48df5803b,
name_67988fb5-2e66-422c-8f7b-ef888011c2af,
name_8730beff-ff90-4dcd-8a0d-2beb31a52758
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_33bd1316-4999-46d3-85e5-9ddaca53a69f,
name_9c32f38b-eaf8-43c2-984a-1651d0915a05,
name_d081ea16-47e7-45ff-917f-28932d814377,
name_7131a853-b4e8-4015-9d30-8f7458942210
result, different first party:
name_33bd1316-4999-46d3-85e5-9ddaca53a69f,
name_9c32f38b-eaf8-43c2-984a-1651d0915a05,
name_d081ea16-47e7-45ff-917f-28932d814377,
name_7131a853-b4e8-4015-9d30-8f7458942210
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_7b84532e-f084-44e3-aa09-ae363cdf0d98,
name_f2a168b9-8331-4566-9610-e21bb2e22f49,
name_f01bbe0f-0d79-4486-a29e-2cc9ef008c2c,
name_3fff33a4-7253-453a-984b-da801d2908c7
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_58d7ea3d-bc86-4d56-b321-b24cad217a6a,
name_2c6db9eb-51b1-4d20-a720-4683792abdd8,
name_c4ff6353-1aa5-4268-aad6-89d84a93ecea,
name_2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
result, different first party:
name_58d7ea3d-bc86-4d56-b321-b24cad217a6a,
name_2c6db9eb-51b1-4d20-a720-4683792abdd8,
name_c4ff6353-1aa5-4268-aad6-89d84a93ecea,
name_2d68a9ce-f490-413f-bf30-3cfe8c1a2d40
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_e562b156-0446-4843-b127-bdb747121163,
name_bf90e98b-1dc5-4d38-8681-b79735bbd28e,
name_fa0f41b8-9e8b-4936-8758-3e3e1d089a8d,
name_15adac17-f3ec-4895-bcce-c50fd0b1cb0b
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_e3f2b7df-fc8a-48d6-be00-2bf760b164b9,
name_d98cf9ec-ee64-41cf-b856-434139cd9692,
name_834e1991-6732-4c97-96a7-3e96c7c393f8,
name_728dc540-0d41-4e86-b473-e3c7ba24bf8c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
name_c42e2e78-39cf-4511-988d-2adcabe85a3a,
name_4cb85808-a298-427e-a095-2112f89a0ebe,
name_7c6616f8-ff31-44a0-a933-a053ccfd8281
result, different first party:
name_1971b1bf-e419-4e1a-8c40-3830ed5d6a3b,
name_c42e2e78-39cf-4511-988d-2adcabe85a3a,
name_4cb85808-a298-427e-a095-2112f89a0ebe,
name_7c6616f8-ff31-44a0-a933-a053ccfd8281
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Passed
passed: true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Failed
passed: false, false, false, false
result:
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.
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Failed
upgraded: false, false, false, false
passed: false, false, false, false
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
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.
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Failed
upgraded: false, false, false, false
passed: false, false, false, false
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
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
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
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
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: 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: encrypted
passed: true, false, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true
Failed
SNI_status: encrypted
passed: true, true, false, true
Failed
SNI_status: plaintext
passed: false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true
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.
Passed
header value: 1
passed: true, true, true, true
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Passed
header value: 1
passed: true, true, true, true
Failed
header value: undefined
passed: 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.
Passed
sec-gpc: 1
passed: true, true, true, true
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Passed
sec-gpc: 1
passed: true, true, true, true
Failed
passed: 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
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
passed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Passed
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: false, false, false, false
readSameFirstParty:
2a0f:df00:0:255::200,
2001:67c:6ec:203:192:42:116:177,
2a03:4000:48:4d:88c8:8eff:fee8:9d1a,
2001:67c:6ec:203:192:42:116:218
readDifferentFirstParty:
2001:67c:6ec:203:192:42:116:184,
2a0b:f4c2:1::1,
2a03:4000:66:15:18a0:6bff:fe90:3147,
107.189.4.209
passed: true, true, true, true
testFailed: 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
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: 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
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Passed
IsTorExit: true, true, true, true
passed: true, true, true, true
Failed
IsTorExit: false, false, false, false
passed: 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.
Passed
expression: undefined
desired expression: undefined
actual value: 1289,1287,1292,1295
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: 900,900,900,900
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Media query screen width
Width of the user's screen in pixels.
Passed
expression: undefined
desired expression: undefined
actual value: 1159,1163,1158,1161
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: 1400,1400,1400,1400
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
outerHeight
Height of the browser window in pixels, including browser chrome.
Passed
expression: outerHeight
desired expression: undefined
actual value: 1289,1287,1292,1295
desired value: undefined
passed: true,true,true,true
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,1371,1371,1371
desired value: undefined
passed: false,false,false,false
Passed
expression: outerHeight
desired expression: undefined
actual value: 1131,1131,1131,1131
desired value: undefined
passed: true,true,true,true
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,1371,1371,1371
desired value: undefined
passed: false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1040,1040,1040,1040
desired value: undefined
passed: false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1061,1061,1061,1061
desired value: undefined
passed: false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 940,940,940,940
desired value: undefined
passed: false,false,false,false
Passed
expression: outerHeight
desired expression: undefined
actual value: 900,900,900,900
desired value: undefined
passed: true,true,true,true
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,0,0,0
desired value: undefined
passed: false,false,false,false
screen.height
Height of the user's screen, in pixels.
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Passed
expression: screen.height
desired expression: undefined
actual value: 900,900,900,900
desired value: undefined
passed: true,true,true,true
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
screen.width
Width of the user's screen, in pixels.
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Passed
expression: screen.width
desired expression: undefined
actual value: 1400,1400,1400,1400
desired value: undefined
passed: true,true,true,true
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: 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: 7,2,7,6
desired value: undefined
passed: true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 22,22,22,22
desired value: undefined
passed: false,false,false,false
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0
desired value: undefined
passed: true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 22,22,22,22
desired value: undefined
passed: false,false,false,false
Passed
expression: screenX
desired expression: undefined
actual value: 4,4,4,4
desired value: undefined
passed: true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 320,320,320,320
desired value: undefined
passed: false,false,false,false
Failed
expression: screenX
desired expression: undefined
actual value: 628,628,628,628
desired value: undefined
passed: false,false,false,false
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0
desired value: undefined
passed: true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 22,0,0,0
desired value: undefined
passed: false,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: 6,2,6,1
desired value: undefined
passed: true,true,true,true
Failed
expression: screenY
desired expression: undefined
actual value: 47,47,47,47
desired value: undefined
passed: false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 47,47,47,47
desired value: undefined
passed: false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 25,25,25,25
desired value: undefined
passed: false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 202,202,202,202
desired value: undefined
passed: false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 324,324,324,324
desired value: undefined
passed: false,false,false,false
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0
desired value: undefined
passed: true,true,true,true
Failed
expression: screenY
desired expression: undefined
actual value: 47,0,0,0
desired value: undefined
passed: false,true,true,true
System font detection
Web pages can detect the presence of a font installed on the user's system. The presence or absence of various fonts is commonly used to fingerprint users.
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
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
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
__hssc
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
__hstc
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
__s
Drip.com email address tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
_hsenc
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
_openstat
Yandex tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
dclid
DoubleClick Click ID (Google)
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
fbclid
Facebook Click Identifier
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
gclid
Google Click Identifier
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
hsCtaTracking
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
mc_eid
Mailchimp Email ID (email recipient's address)
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
mkt_tok
Adobe Marketo tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
ml_subscriber
MailerLite email tracking
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
ml_subscriber_hash
MailerLite email tracking
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
msclkid
Microsoft Click ID
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
oly_anon_id
Omeda marketing 'anonymous' customer id
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
oly_enc_id
Omeda marketing 'known' customer id
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
rb_clickid
Unknown high-entropy tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
s_cid
Adobe Site Catalyst tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
vero_conv
Vero tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
vero_id
Vero tracking parameter
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
wickedid
Wicked Reports e-commerce tracking
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
yclid
Yandex Click ID
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Failed
value: 9249524776082134
passed: false, false, false, false
Passed
passed: true, true, true, true
Failed
value: 9249524776082134
passed: 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
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: 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
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: 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
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: 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
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: 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
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: 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
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: 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
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: 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
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: 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
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: 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
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: 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
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: 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
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: 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
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: 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
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: 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
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: 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
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: 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
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
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: 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
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: 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
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: 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
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: 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
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Failed
url: https://t.co/i/adsct
passed: 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
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Tracking cookie protection testsWhich browsers block important known tracking cookies?
A large fraction of web pages on the web have hidden third-party trackers that read and write cookies in your browser. These cookies can be used to track your browsing across websites. This section checks to see if a browser stops cross-site tracking by cookies from 20 of the largest trackers listed by https://whotracks.me.`,
Adobe
Tests whether the browser stops cookies from munchkin.marketo.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Failed
passed: true, false, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, true, false, false
Adobe Audience Manager
Tests whether the browser stops cookies from dpm.demdex.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://dpm.demdex.net/ibs
cookieFound: true, true, false, false
Amazon adsystem
Tests whether the browser stops cookies from s.amazon-adsystem.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Failed
passed: false, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, false, false, false
AppNexus
Tests whether the browser stops cookies from ib.adnxs.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Failed
passed: true, false, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, true, false, false
Bing Ads
Tests whether the browser stops cookies from bat.bing.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Failed
passed: true, false, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, true, false, false
Chartbeat
Tests whether the browser stops cookies from static.chartbeat.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Criteo
Tests whether the browser stops cookies from dis.criteo.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Failed
passed: false, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, false, false, false
DoubleClick (Google)
Tests whether the browser stops cookies from securepubads.g.doubleclick.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, true, true, true
Facebook tracking
Tests whether the browser stops cookies from connect.facebook.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, true, false, false
Google (third-party ad pixel)
Tests whether the browser stops cookies from www.google.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, true, false, false
Google Analytics
Tests whether the browser stops cookies from google-analytics.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://google-analytics.com/urchin.js
cookieFound: true, true, false, false
Google Tag Manager
Tests whether the browser stops cookies from www.googletagmanager.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Index Exchange
Tests whether the browser stops cookies from dsum-sec.casalemedia.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, true, false, false
New Relic
Tests whether the browser stops cookies from js-agent.newrelic.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Failed
passed: true, false, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, true, false, false
Quantcast
Tests whether the browser stops cookies from pixel.quantserve.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: true, true, false, false
Scorecard Research Beacon
Tests whether the browser stops cookies from sb.scorecardresearch.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, false, false
Taboola
Tests whether the browser stops cookies from trc.taboola.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Twitter pixel
Tests whether the browser stops cookies from t.co from tracking users across websites.
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Failed
passed: false, false, true, true
url: https://t.co/i/adsct
cookieFound: true, true, false, false
Yandex Ads
Tests whether the browser stops cookies from yandex.ru from tracking users across websites.
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Failed
passed: false, false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: 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.
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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, h3, h2
result, different session: h3, h2, h2, h3
unsupported: true, false, false, true
passed: , true, true
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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, h3, h2
result, different session: h3, h2, h2, h3
unsupported: true, false, false, true
passed: , true, true
test failed: 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
result, different session: h2, h2, h2, h2
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
4604fca6-7d8f-4577-bd1b-a621e735382e_1p,
26908635-2334-4e48-931b-f5d48df5803b_1p,
67988fb5-2e66-422c-8f7b-ef888011c2af_1p,
8730beff-ff90-4dcd-8a0d-2beb31a52758_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')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
e562b156-0446-4843-b127-bdb747121163_1p,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_1p,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_1p,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_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')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_1p,
d98cf9ec-ee64-41cf-b856-434139cd9692_1p,
834e1991-6732-4c97-96a7-3e96c7c393f8_1p,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_1p
result, different session:
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p_http,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p_http,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p_http,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p_http
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p_http,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p_http,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p_http,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p_http,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p_http,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p_http,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p_http
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p_http,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p_http,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p_http,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
4604fca6-7d8f-4577-bd1b-a621e735382e_1p_http,
26908635-2334-4e48-931b-f5d48df5803b_1p_http,
67988fb5-2e66-422c-8f7b-ef888011c2af_1p_http,
8730beff-ff90-4dcd-8a0d-2beb31a52758_1p_http
result, different session:
4604fca6-7d8f-4577-bd1b-a621e735382e_1p_http,
26908635-2334-4e48-931b-f5d48df5803b_1p_http,
67988fb5-2e66-422c-8f7b-ef888011c2af_1p_http,
8730beff-ff90-4dcd-8a0d-2beb31a52758_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p_http,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p_http,
d081ea16-47e7-45ff-917f-28932d814377_1p_http,
7131a853-b4e8-4015-9d30-8f7458942210_1p_http
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p_http,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p_http,
d081ea16-47e7-45ff-917f-28932d814377_1p_http,
7131a853-b4e8-4015-9d30-8f7458942210_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p_http,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p_http,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p_http,
3fff33a4-7253-453a-984b-da801d2908c7_1p_http
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p_http,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p_http,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p_http,
3fff33a4-7253-453a-984b-da801d2908c7_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p_http,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p_http,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p_http,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p_http
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p_http,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p_http,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p_http,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
e562b156-0446-4843-b127-bdb747121163_1p_http,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_1p_http,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_1p_http,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_1p_http
result, different session:
e562b156-0446-4843-b127-bdb747121163_1p_http,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_1p_http,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_1p_http,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_1p_http,
d98cf9ec-ee64-41cf-b856-434139cd9692_1p_http,
834e1991-6732-4c97-96a7-3e96c7c393f8_1p_http,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_1p_http
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p_http,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p_http,
4cb85808-a298-427e-a095-2112f89a0ebe_1p_http,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p_http
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p_http,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p_http,
4cb85808-a298-427e-a095-2112f89a0ebe_1p_http,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p_js,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p_js,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p_js,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p_js
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p_js,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p_js,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p_js,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p_js,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p_js,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p_js,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p_js
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p_js,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p_js,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p_js,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
4604fca6-7d8f-4577-bd1b-a621e735382e_1p_js,
26908635-2334-4e48-931b-f5d48df5803b_1p_js,
67988fb5-2e66-422c-8f7b-ef888011c2af_1p_js,
8730beff-ff90-4dcd-8a0d-2beb31a52758_1p_js
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p_js,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p_js,
d081ea16-47e7-45ff-917f-28932d814377_1p_js,
7131a853-b4e8-4015-9d30-8f7458942210_1p_js
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p_js,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p_js,
d081ea16-47e7-45ff-917f-28932d814377_1p_js,
7131a853-b4e8-4015-9d30-8f7458942210_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p_js,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p_js,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p_js,
3fff33a4-7253-453a-984b-da801d2908c7_1p_js
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p_js,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p_js,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p_js,
3fff33a4-7253-453a-984b-da801d2908c7_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p_js,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p_js,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p_js,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p_js
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p_js,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p_js,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p_js,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
e562b156-0446-4843-b127-bdb747121163_1p_js,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_1p_js,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_1p_js,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_1p_js
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_1p_js,
d98cf9ec-ee64-41cf-b856-434139cd9692_1p_js,
834e1991-6732-4c97-96a7-3e96c7c393f8_1p_js,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_1p_js
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p_js,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p_js,
4cb85808-a298-427e-a095-2112f89a0ebe_1p_js,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p_js
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p_js,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p_js,
4cb85808-a298-427e-a095-2112f89a0ebe_1p_js,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
Failed
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_2356512427522066,
fake_806968485510053,
fake_9964360102041652,
fake_06230925675968546
result, different session:
fake_2356512427522066,
fake_806968485510053,
fake_9964360102041652,
fake_06230925675968546
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_0635292156438978,
fake_8654285132515536,
fake_44865984015178295,
fake_893459614362073
result, different session:
fake_0635292156438978,
fake_8654285132515536,
fake_44865984015178295,
fake_893459614362073
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_8517416832602365,
fake_257791619470672,
fake_7945588882733698,
fake_1325054663396934
result, different session:
fake_8517416832602365,
fake_257791619470672,
fake_7945588882733698,
fake_1325054663396934
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_44811139178095094,
fake_34393385752789585,
fake_24826930314172602,
fake_26618320433475695
result, different session:
fake_44811139178095094,
fake_34393385752789585,
fake_24826930314172602,
fake_26618320433475695
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_20198016222329973,
fake_09958636517124941,
fake_46455385243333747,
fake_2578219993259343
result, different session:
fake_20198016222329973,
fake_09958636517124941,
fake_46455385243333747,
fake_2578219993259343
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_8016316312483853,
fake_2694995325789753,
fake_4982904105970771,
fake_034593745507768725
result, different session:
fake_8016316312483853,
fake_2694995325789753,
fake_4982904105970771,
fake_034593745507768725
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_5158223830929218,
fake_6273917356409127,
fake_6333656591768333,
fake_7436759853792179
result, different session:
fake_5158223830929218,
fake_6273917356409127,
fake_6333656591768333,
fake_7436759853792179
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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_09704871722289976,
fake_03370245141367434,
fake_9620645960439815,
fake_07967044068912532
result, different session:
fake_4953465485081965,
fake_20536959246162123,
fake_21784829515413828,
fake_7848001896281296
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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_502709701967381,
fake_9943156772658488,
fake_8823625260587804,
fake_6979944516797654
result, different session:
fake_502709701967381,
fake_9943156772658488,
fake_8823625260587804,
fake_6979944516797654
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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 session: 1, 1, 1, 1
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
4604fca6-7d8f-4577-bd1b-a621e735382e_1p,
26908635-2334-4e48-931b-f5d48df5803b_1p,
67988fb5-2e66-422c-8f7b-ef888011c2af_1p,
8730beff-ff90-4dcd-8a0d-2beb31a52758_1p
result, different session: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
e562b156-0446-4843-b127-bdb747121163_1p,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_1p,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_1p,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_1p
result, different session: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_1p,
d98cf9ec-ee64-41cf-b856-434139cd9692_1p,
834e1991-6732-4c97-96a7-3e96c7c393f8_1p,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_1p
result, different session: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_1p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_1p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_1p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_1p,
3c23ace0-158e-452e-bd97-8e1b2e653552_1p,
9ac4ca03-961e-43fc-9d79-14910801fe63_1p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
4604fca6-7d8f-4577-bd1b-a621e735382e_1p,
26908635-2334-4e48-931b-f5d48df5803b_1p,
67988fb5-2e66-422c-8f7b-ef888011c2af_1p,
8730beff-ff90-4dcd-8a0d-2beb31a52758_1p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_1p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_1p,
d081ea16-47e7-45ff-917f-28932d814377_1p,
7131a853-b4e8-4015-9d30-8f7458942210_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_1p,
f2a168b9-8331-4566-9610-e21bb2e22f49_1p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_1p,
3fff33a4-7253-453a-984b-da801d2908c7_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_1p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_1p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_1p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
e562b156-0446-4843-b127-bdb747121163_1p,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_1p,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_1p,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_1p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
e3f2b7df-fc8a-48d6-be00-2bf760b164b9_1p,
d98cf9ec-ee64-41cf-b856-434139cd9692_1p,
834e1991-6732-4c97-96a7-3e96c7c393f8_1p,
728dc540-0d41-4e86-b473-e3c7ba24bf8c_1p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_1p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_1p,
4cb85808-a298-427e-a095-2112f89a0ebe_1p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h2, h3, h3, h3
unsupported: false, false, false, false
passed: true, false, false, false
test failed: 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
result, different session: h3, h3, h3, h3
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h2, h3, h3, h3
unsupported: false, false, false, false
passed: true, false, false, false
test failed: 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
result, different session: h2, h2, h2, h2
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different session: h2, h2, h2, h2
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
4604fca6-7d8f-4577-bd1b-a621e735382e_3p,
26908635-2334-4e48-931b-f5d48df5803b_3p,
67988fb5-2e66-422c-8f7b-ef888011c2af_3p,
8730beff-ff90-4dcd-8a0d-2beb31a52758_3p
result, different session:
4604fca6-7d8f-4577-bd1b-a621e735382e_3p,
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false
passed: false, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_3p,
f2a168b9-8331-4566-9610-e21bb2e22f49_3p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_3p,
3fff33a4-7253-453a-984b-da801d2908c7_3p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_3p,
f2a168b9-8331-4566-9610-e21bb2e22f49_3p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_3p,
3fff33a4-7253-453a-984b-da801d2908c7_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
e562b156-0446-4843-b127-bdb747121163_3p,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_3p,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_3p,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_3p
result, different session:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Unsupported
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
result, different session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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 session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p_http,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p_http,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p_http,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p_http
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p_http,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p_http,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p_http,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p_http
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p_http,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p_http,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p_http,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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
passed: undefined
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p_http,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p_http,
d081ea16-47e7-45ff-917f-28932d814377_3p_http,
7131a853-b4e8-4015-9d30-8f7458942210_3p_http
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p_http,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p_http,
d081ea16-47e7-45ff-917f-28932d814377_3p_http,
7131a853-b4e8-4015-9d30-8f7458942210_3p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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
passed: undefined
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p_http,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p_http,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p_http,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p_http
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p_http,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p_http,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p_http,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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
passed: undefined
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , ,
result, different session: , , ,
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p_http,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p_http,
4cb85808-a298-427e-a095-2112f89a0ebe_3p_http,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p_http
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p_http,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p_http,
4cb85808-a298-427e-a095-2112f89a0ebe_3p_http,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p_js,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p_js,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p_js,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p_js
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p_js,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p_js,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p_js,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p_js
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p_js,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p_js,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p_js,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , ,
result, different session: , , ,
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p_js,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p_js,
d081ea16-47e7-45ff-917f-28932d814377_3p_js,
7131a853-b4e8-4015-9d30-8f7458942210_3p_js
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p_js,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p_js,
d081ea16-47e7-45ff-917f-28932d814377_3p_js,
7131a853-b4e8-4015-9d30-8f7458942210_3p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , ,
result, different session: , , ,
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p_js,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p_js,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p_js,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p_js
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p_js,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p_js,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p_js,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , ,
result, different session: , , ,
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${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
passed: undefined
test failed: 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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p_js,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p_js,
4cb85808-a298-427e-a095-2112f89a0ebe_3p_js,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p_js
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p_js,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p_js,
4cb85808-a298-427e-a095-2112f89a0ebe_3p_js,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
Passed
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:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
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:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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: , , ,
result, different session: , , ,
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different session:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_6832707673871388,
fake_679996777549849,
fake_6073661163373141,
fake_4106391003717649
result, different session:
fake_6832707673871388,
fake_679996777549849,
fake_6073661163373141,
fake_4106391003717649
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_47865790639990036,
fake_3991981089432717,
fake_896352991654388,
fake_262187614800532
result, different session:
fake_47865790639990036,
fake_3991981089432717,
fake_896352991654388,
fake_262187614800532
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_27771193705483044,
fake_7911432680580048,
fake_1106659231307634,
fake_14270706189713533
result, different session:
fake_27771193705483044,
fake_7911432680580048,
fake_1106659231307634,
fake_14270706189713533
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3695251830159749,
fake_4884603984586793,
fake_4322487225860103,
fake_633160929403876
result, different session:
fake_3695251830159749,
fake_4884603984586793,
fake_4322487225860103,
fake_633160929403876
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_31532818721825584,
fake_33268281132692,
fake_269382118011839,
fake_6381118399471664
result, different session:
fake_31532818721825584,
fake_33268281132692,
fake_269382118011839,
fake_6381118399471664
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_08805343874058202,
fake_04385968498517645,
fake_3455316329950928,
fake_9939921205423685
result, different session:
fake_08805343874058202,
fake_04385968498517645,
fake_3455316329950928,
fake_9939921205423685
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_35380071332267105,
fake_40818449639726606,
fake_36490281331087027,
fake_11517011099231489
result, different session:
fake_35380071332267105,
fake_40818449639726606,
fake_36490281331087027,
fake_11517011099231489
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_5552845090659384,
fake_71314056556583,
fake_10809883756069505,
fake_30856398668540375
result, different session:
fake_6231294913015779,
fake_21066826325401244,
fake_9849731543125304,
fake_13862648449297166
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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_0956832645113399,
fake_6145128696801943,
fake_9587952235895416,
fake_7713900371148521
result, different session:
fake_0956832645113399,
fake_6145128696801943,
fake_9587952235895416,
fake_7713900371148521
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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, 2, 1
result, different session: 1, 1, 2, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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 session: 1, 1, 1, 1
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
4604fca6-7d8f-4577-bd1b-a621e735382e_3p,
26908635-2334-4e48-931b-f5d48df5803b_3p,
67988fb5-2e66-422c-8f7b-ef888011c2af_3p,
8730beff-ff90-4dcd-8a0d-2beb31a52758_3p
result, different session: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
7b84532e-f084-44e3-aa09-ae363cdf0d98_3p,
f2a168b9-8331-4566-9610-e21bb2e22f49_3p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_3p,
3fff33a4-7253-453a-984b-da801d2908c7_3p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_3p,
f2a168b9-8331-4566-9610-e21bb2e22f49_3p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_3p,
3fff33a4-7253-453a-984b-da801d2908c7_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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:
e562b156-0446-4843-b127-bdb747121163_3p,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_3p,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_3p,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_3p
result, different session: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Unsupported
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure
result, different session:
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure
unsupported: true, true, true, true
passed: undefined
test failed: 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:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
result, different session:
6ed9ecc6-966f-4b36-91e6-7119813d3d78_3p,
abb4921b-1ec6-4a31-aa47-9b6bc2693982_3p,
ad61cd3b-7f21-44f8-bc0f-9399664c267e_3p,
ae71b7e5-0054-4b93-b9ba-b54f65690acc_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
result, different session:
0924fe4a-d12e-4351-8776-0578cfc20dba_3p,
3c23ace0-158e-452e-bd97-8e1b2e653552_3p,
9ac4ca03-961e-43fc-9d79-14910801fe63_3p,
f856f5fe-f8d2-4a28-bf0c-8a2002d46f50_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
4604fca6-7d8f-4577-bd1b-a621e735382e_3p,
26908635-2334-4e48-931b-f5d48df5803b_3p,
67988fb5-2e66-422c-8f7b-ef888011c2af_3p,
8730beff-ff90-4dcd-8a0d-2beb31a52758_3p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
result, different session:
33bd1316-4999-46d3-85e5-9ddaca53a69f_3p,
9c32f38b-eaf8-43c2-984a-1651d0915a05_3p,
d081ea16-47e7-45ff-917f-28932d814377_3p,
7131a853-b4e8-4015-9d30-8f7458942210_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_3p,
f2a168b9-8331-4566-9610-e21bb2e22f49_3p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_3p,
3fff33a4-7253-453a-984b-da801d2908c7_3p
result, different session:
7b84532e-f084-44e3-aa09-ae363cdf0d98_3p,
f2a168b9-8331-4566-9610-e21bb2e22f49_3p,
f01bbe0f-0d79-4486-a29e-2cc9ef008c2c_3p,
3fff33a4-7253-453a-984b-da801d2908c7_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
result, different session:
58d7ea3d-bc86-4d56-b321-b24cad217a6a_3p,
2c6db9eb-51b1-4d20-a720-4683792abdd8_3p,
c4ff6353-1aa5-4268-aad6-89d84a93ecea_3p,
2d68a9ce-f490-413f-bf30-3cfe8c1a2d40_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
e562b156-0446-4843-b127-bdb747121163_3p,
bf90e98b-1dc5-4d38-8681-b79735bbd28e_3p,
fa0f41b8-9e8b-4936-8758-3e3e1d089a8d_3p,
15adac17-f3ec-4895-bcce-c50fd0b1cb0b_3p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Unsupported
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
result, different session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
result, different session:
1971b1bf-e419-4e1a-8c40-3830ed5d6a3b_3p,
c42e2e78-39cf-4511-988d-2adcabe85a3a_3p,
4cb85808-a298-427e-a095-2112f89a0ebe_3p,
7c6616f8-ff31-44a0-a933-a053ccfd8281_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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.
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: 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
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true
passed: undefined
test failed: false, false, false, false
Failed
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: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: 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
result, different session: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: 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
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
DNS privacy testsWhich browsers keep their DNS queries encrypted?
The Domain Name System (DNS) is the method by which web browsers look up the IP address for each website you visit. In a DNS query, a web browser will ask a DNS resolver (somewhere on the internet) for the IP address corresponding to a domain name (such as nytimes.com) for a website you want to visit. Traditionally, most web browsers have sent their DNS queries unencrypted, which means your ISP or anyone else on the network between your computer and the DNS resolver can eavesdrop on the websites you visit. In recent years, web browsers and operating systems have begun to introduce encrypted DNS, including the DNS over HTTPS (DoH) protocol, to encrypt the DNS request from your browser and the response from the resolver to keep your browsing history from leaking. These tests check whether a browser is still protecting its DNS requests by sending them encrypted.
Location: Brazil
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Brazil.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Location: China
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in China.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Location: Germany
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Germany.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Location: India
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in India.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Location: Nigeria
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Nigeria.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Location: Russia
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Russia.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Location: United States
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in United States.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
OS DNS: Cloudflare
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Cloudflare.
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
OS DNS: Comodo
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Comodo.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
OS DNS: Google
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Google.
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
OS DNS: Quad9
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Quad9.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true