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1.95

private
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1.95

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private
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, h3
result, different first party: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party: h3, h3, h3, h3, h3
result, different first party: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party: h3, h3, h3
result, different first party: h2, h2, h2
unsupported: false, false, false
passed: true, true, true
test failed: 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, h3
result, different first party: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party: h3, h3, h3, h3, h3
result, different first party: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same first party: h3, h3, h3, h3, h3
result, different first party: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
blob
A 'blob URL' is a local reference to some raw data. Trackers can use a blob URL to share data between websites.
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
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.,
Error: NetworkError when attempting to fetch resource.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${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:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
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.,
Error: NetworkError when attempting to fetch resource.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false
passed: true, true, true
test failed: 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:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party:
Error: The operation is insecure.,
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, false
passed: true, true, true, true, true
test failed: false, 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:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
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')
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party:
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6_http,
983d7a98-4d47-4939-9fde-d29cc857c4f5_http,
932e9a95-68ef-4e18-9e6a-6888f8984bce_http,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_http,
11a5432e-af5d-47ac-9573-7b79701cf158_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_http,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_http,
f830b9fa-d053-421d-b45e-ee70f920d327_http,
7a958105-b259-466d-b7c1-7c84dac324d1_http,
f8325715-9f9d-4b2a-843d-81922950b028_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28_http,
73489d4d-045a-4a14-9a36-c930f96cc1da_http,
7e9bbe57-0313-457c-94b3-9b03c21e905e_http,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_http,
d25d4d13-aa43-40f1-bd46-e387c8392518_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_http,
174c6491-118a-4f4e-8d3b-a5897bb68365_http,
b6d43ee5-d8cf-4a09-999e-603533c121fe_http,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_http,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_http,
219ddc64-b2d9-459a-80ad-10bac6d62a02_http,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_http
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
f8ffedfe-aa49-42e0-9767-3241fc941429_http,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_http,
231555b0-11a9-4057-8e14-df0ea284c964_http,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_http,
b9afa08a-70bb-4887-b8a2-04be55ffe313_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a_http,
3eed10d3-8421-422f-bdae-c0a33ca26848_http,
8c28c559-9404-41c8-8135-0a2be28ff426_http,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_http,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e_http,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_js,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_http,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_http,
6848c438-def7-48c3-bf4d-d0387b56e58d_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_http,
5b090fae-53dc-463e-bad6-7b057a7774bb_http,
8e764661-91bb-46a4-92f8-f598653497f0_http,
e651769f-311b-4111-aa86-57e477e5c1cd_http,
0df21732-f557-4c6a-920b-a3f813eaf9ea_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6_js,
983d7a98-4d47-4939-9fde-d29cc857c4f5_js,
932e9a95-68ef-4e18-9e6a-6888f8984bce_js,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_js,
11a5432e-af5d-47ac-9573-7b79701cf158_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_js,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_js,
f830b9fa-d053-421d-b45e-ee70f920d327_js,
7a958105-b259-466d-b7c1-7c84dac324d1_js,
f8325715-9f9d-4b2a-843d-81922950b028_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28_js,
73489d4d-045a-4a14-9a36-c930f96cc1da_js,
7e9bbe57-0313-457c-94b3-9b03c21e905e_js,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_js,
d25d4d13-aa43-40f1-bd46-e387c8392518_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_js,
174c6491-118a-4f4e-8d3b-a5897bb68365_js,
b6d43ee5-d8cf-4a09-999e-603533c121fe_js,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_js,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_js,
219ddc64-b2d9-459a-80ad-10bac6d62a02_js,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_js
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
f8ffedfe-aa49-42e0-9767-3241fc941429_js,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_js,
231555b0-11a9-4057-8e14-df0ea284c964_js,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_js,
b9afa08a-70bb-4887-b8a2-04be55ffe313_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a_js,
3eed10d3-8421-422f-bdae-c0a33ca26848_js,
8c28c559-9404-41c8-8135-0a2be28ff426_js,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_js,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e_js,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_js,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_js,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_js,
6848c438-def7-48c3-bf4d-d0387b56e58d_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_js,
5b090fae-53dc-463e-bad6-7b057a7774bb_js,
8e764661-91bb-46a4-92f8-f598653497f0_js,
e651769f-311b-4111-aa86-57e477e5c1cd_js,
0df21732-f557-4c6a-920b-a3f813eaf9ea_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
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:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: 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:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_6329495786324351,
fake_9246694726134435,
fake_21195126182055346,
fake_7613211027441342,
fake_6929283048266801
result, different first party:
fake_8761215353286771,
fake_35905516696403605,
fake_5354635009894835,
fake_005210581215243204,
fake_3767699237690363
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_3595499051786606,
fake_45613945840556225,
fake_019199711291472132,
fake_6411131928598777,
fake_1953254488595717
result, different first party:
fake_024313935148781107,
fake_7166062001653652,
fake_34329356683690393,
fake_32646106339532777,
fake_8564398613534643
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_08864264482380246,
fake_03634613273690834,
fake_2136824691149195,
fake_5826126640665683,
fake_5422815068859224
result, different first party:
fake_08864264482380246,
fake_03634613273690834,
fake_3674642499884253,
fake_5826126640665683,
fake_5422815068859224
unsupported: false, false, false, false, false
passed: false, false, true, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_4401227186247334,
fake_8332886346880086,
fake_08048751121334652,
fake_05241779271501468,
fake_14149711244051955
result, different first party:
fake_5517684534351133,
fake_5932683002441062,
fake_3817951196032334,
fake_2506204524109559,
fake_4343219175361208
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_657953343094422,
fake_2251611781239744,
fake_6637770551085989
result, different first party:
fake_657953343094422,
fake_2251611781239744,
fake_6637770551085989
unsupported: false, false, false
passed: false, false, false
test failed: 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_6865370723825388,
fake_06933073996148509,
fake_05388865440551349,
fake_9015478737530356,
fake_019393496605723426
result, different first party:
fake_49145809638773774,
fake_330611771792527,
fake_25997587672165734,
fake_5909337445558829,
fake_48834731712656043
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_9730239291788185,
fake_4152065042948754,
fake_9545974282935195,
fake_8576764996906796,
fake_014133981149422992
result, different first party:
fake_2126289520884459,
fake_4152065042948754,
fake_9545974282935195,
fake_8576764996906796,
fake_1897875113418841
unsupported: false, false, false, false, false
passed: true, false, false, false, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_27999886184400546,
fake_7199384296708973,
fake_6651698777210382,
fake_04942865738978308,
fake_9744393783914831
result, different first party:
fake_9067622963911095,
fake_5815365427486188,
fake_8933496319456489,
fake_5480878765512187,
fake_6287766374716586
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same first party:
fake_21741836878531107,
fake_7534169335386849,
fake_07185662710198693,
fake_6603105910731588,
fake_0708294100249971
result, different first party:
fake_21741836878531107,
fake_2277571661801412,
fake_07185662710198693,
fake_6603105910731588,
fake_6759889418235958
unsupported: false, false, false, false, false
passed: false, true, false, false, true
test failed: false, false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 2
result, different first party: 3, 3, 3, 3, 3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: 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, 1
result, different first party: 1, 1, 2, 1, 1
unsupported: false, false, false, false, false
passed: false, false, true, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: 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
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: 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, 1
result, different first party: 2, 1, 1, 1, 2
unsupported: false, false, false, false, false
passed: true, false, false, false, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: 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, 1
result, different first party: 1, 2, 1, 1, 2
unsupported: false, false, false, false, false
passed: false, true, false, false, true
test failed: false, false, false, false, false
getDirectory
navigator.storage.getDirectory exposes a location for storing files to web content. In some cases, these files may be shared across tabs.
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:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
H1 connection
HTTP/1.x are the classic web connection protocols. If these connections are re-used across websites, they can be used to track users.
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${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:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
H2 connection
HTTP/2 is a web connection protocol introduced in 2015. Some browsers re-use HTTP/2 connections across websites and can thus be used to track users.
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }
read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
H3 connection
HTTP/3 is a new standard HTTP connection protocol, still in draft but widely supported by browsers. If it is not partitioned, it can be used to track users across websites.
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party:
39ab1cabdb6fb6e45996aa24cdef9870,
3f32fa51924cf2923544382a09bc8348,
8f69358366665b1bfc420febc44456fd,
1dfe9878a16063907ae16639327643e6,
2b6ed98876b8624e98f7cc6cf4d75a1c
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party:
271d35fb611927c799cbca8d3cb4d9c2,
f12c617e908f859b699d4445dfebacf4,
e4d7ec27203d0a9323f717ae81633f43,
351d211a1f9068a845b091f31ea4b842,
ecc731e7eb5c6b179f94e0782c6c4000
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party:
08189b6f2f788e36b33b671bb1cca929,
6979f363131d69f8e57f34a936c0b892,
329bacfc1a69c8d969a56fa899c32166
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: 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:
4f73100f4da54f7e15697f27fe6eac4c,
6541337a4a63db4873c94e2684d54e02,
97fdcd93d3e5605c76c82db0fc4741c0,
762a9cb827df496b182b9f8ebe79b61d,
9e84015ee4f2f5a46d5a991a5dcbfb2b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // 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:
a5a434b0d51ff6a6dc803d5b2df65ac1,
af901be0c172f61f4133521a05f8fd71,
d117e42ad24488dd99ca59206eed2a08,
12134efb60c0eda22eb8a6a215a7ed32,
b4d22b3649b90899021df7a41fdea41b
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party: , , , ,
result, different first party: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }
result, same first party:
3b19157b8eae0dce4c28c2c0bb01a4e7,
80abb84b8cb5984109d1e6d0b4d53db2,
5faa989a55152acc14e668ef1af6ff7c,
f4951845c578e99a4ad7dbd177258ac7,
9ff4cb71c79b43c575d08f6a0b22102c
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
HSTS cache

            
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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, 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
unsupported: , ,
passed: true, true, true
test failed: false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, false, false, false, false
HSTS cache (fetch)

            
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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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, not tested
result, different first party:
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, 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
unsupported: , ,
passed: true, true, true
test failed: false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, 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,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , , ,
passed: true, true, true, true, true
test failed: false, false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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, 1
result, different first party: 1, 1, 2, 1, 1
unsupported: false, false, false, false, false
passed: false, false, true, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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, 1
result, different first party: 2, 1, 1, 1, 2
unsupported: false, false, false, false, false
passed: true, false, false, false, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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, 1
result, different first party: 1, 2, 1, 1, 2
unsupported: false, false, false, false, false
passed: false, true, false, false, true
test failed: false, false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party: undefined
unsupported: false, false, false
passed: true, true, true
test failed: 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:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
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,
Error: IDBFactory.open: The operation is insecure
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party:
Error: The operation is insecure.,
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, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
locks
navigator.locks (only supported in some browsers) allows scripts on multiple tabs to coordinate. If this API is not partitioned, it can be used for cross-site tracking.
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
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'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
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'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
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'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party:
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name'),
Error: undefined is not an object (evaluating 'queryResult.held[0].name')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
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')
unsupported: false, false, false
passed: true, true, true
test failed: 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:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
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,
Error: LockManager.query: query() is not allowed in this context
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
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'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
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,
Error: LockManager.query: query() is not allowed in this context
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
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'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: 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, 1
result, different first party: 1, 1, 2, 1, 1
unsupported: false, false, false, false, false
passed: false, false, true, false, false
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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 first party: 1, 1, 1
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: 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, 1
result, different first party: 2, 1, 1, 1, 2
unsupported: false, false, false, false, false
passed: true, false, false, false, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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 first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 1, 2
unsupported: false, false, false, false, false
passed: false, true, false, false, true
test failed: false, false, false, false, false
script cache
Caching of scripts in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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, 1
result, different first party: 1, 1, 2, 1, 1
unsupported: false, false, false, false, false
passed: false, false, true, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: 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, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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, 1
result, different first party: 2, 1, 1, 1, 2
unsupported: false, false, false, false, false
passed: true, false, false, false, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => 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, 1
result, different first party: 1, 2, 1, 1, 2
unsupported: false, false, false, false, false
passed: false, true, false, false, true
test failed: false, 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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party: undefined
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party:
Error: no SharedWorker message received,
Error: no SharedWorker message received,
Error: no SharedWorker message received,
Error: no SharedWorker message received,
Error: no SharedWorker message received
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party: undefined
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: Can't find variable: message,
Error: Can't find variable: message,
Error: Can't find variable: message,
Error: Can't find variable: message,
Error: Can't find variable: message
result, different first party: undefined
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party: undefined
unsupported: false, false, false
passed: undefined
test failed: true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party: undefined
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party: undefined
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party:
Error: SharedWorker constructor: StorageAccess denied.,
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, false
passed: undefined
test failed: true, true, true, true, true
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 messge = await messagePromise;
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (message === "none") {
          throw new Error("Unsupported");
        }
      }
    }
result, same first party:
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined,
Error: message is not defined
result, different first party: undefined
unsupported: false, false, false, false, false
passed: undefined
test failed: true, true, true, true, true
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:
863a5cf2e58daf5e8dba7a71854be573306daa9b6058c5ac412fd033f84e5902,
c78313cceccdd42b2c21ac7a3725f8e9bae9ff29cb52defc9f17a54ee0dc86cd,
dc4f093cd27236e9326b5ec17230429521885990ff225689e4b7dcf77286c5a2,
63f9a8304353f79403028ea90fb51ed872715d7a0f510c070c0fd0a902419d2a,
2ff8435c3c9e8177f123b3877c5520039d33ed4854f745f4a5686418b624595c
result, different first party:
0f8c5f5b68180b839c0bc38ee0945ad27e2bb8b700f425876bab202810d6f933,
f7a1672beff456df042b1d527a570b8b277f86d3669307484489688493919e4f,
d07c11f3280ca2f0aee60d27f76394fb0c1e723532be9f946ece4efe6a6f210f,
31b1bb65d280a5a8f0681180747253659ce03108d618ad0fe04eb377022ee348,
1e425bea63361a476ce967533812113fa446d83dd395d91be173eea03b9c14ce
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
83d35422ad33baa72d4ab8f84ebdbabfb79a3170eb5a4558cac9807382239b92,
594fc388003501a4f32c42ee0693f6551533358ad7dbafd58b28d66d6c6efd6d,
ecd2a63a6a216dd5069913a2d178beb43fcb04263bd8a2c213d9d617d52d037a,
f1a27c6d125511b1d4ab83d9a4a2640bb015dc3b1b0dea165b722d6930294b4c,
7cc42e64ca8b81f488d7b2f4d4b962c087d938de45ca8e06d0bbe4ec3b480b17
result, different first party:
1e2afdc4cbd7af068ba4921c19f7b60fb94e7316c77aa47edc7393be23b37c3e,
93f34587d64177dbdfe516cbd3bb09811b2e97b8502b0a6ea2a6a3d8230973e6,
ae4920ba9bc8bd8fb48958f3b72e0faf4b42cf2fa8085a9128016c949a5d1c04,
d18db8966dbe7074f19a7f7c31091e266aefe116cbf2f8746e56a605dec95274,
eefe527cd0562dc9e803d7f42c8d5e67f266ac124301e80cd3c227dfea7db1f2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
112d4ba3be8ed60c1dd75da8a48f8f97573e735666b0bee779cbbce0034f0d67,
d30190dfd3fef964c40f73afd6c300be8bf2d38bebd0520763067d9796560c80,
084ae1ce0b3e81c9d98a59662a7c303a914cc83fd9345c303c8d552f4857d846,
7d9b03b47f0f12074c168fcfffb46fe52e60028747e26a2dfada50929f2bdd45,
5407d5bed093fd1b3669a8212db2d391395f76bc345faa25d0df848c67c61bc7
result, different first party:
a95372c7697801e05e3c4cabc721cb6f1a5fa914441cd6a06c14796f305b0583,
0d4080972d83154bb9b151db19a89ebc5d172420ac9ebbdc9470b797a0e2a7fb,
4abe1c22b90c93a1a28984e673926876284159a603a4385424781bef4d8fae96,
c65176c5b58fb65097e85f1a1a9f311b3e01b4b940813dbea11389504111c8d8,
d9c242fc3d193b5277fa1dfcdda4d67aebf7a8e5cca72be0994b8893c1ecd745
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
d16e202270675ed8f59f98e390309e2dd5aa10d4e14f0e8d75cc85ba99af6f1d,
76eaa3a99cf2efe5a8762dd01d916734f4f4e5fad9db11df25f52ae5a4d21113,
ad68abd108731a80b8bd46c2d2a103f6800a4e57e0ac4a553ec6b4a2be46d172,
72cb842ad7cbd7ca43213f78fd4d13884663848a5c07540e28b283394e9e7138,
9f289bb7383ecd7e44e5ad008fa85fc2a282304708bde289a65c29c6290818e9
result, different first party:
19cefd8bddcc1bc486bf71a602c3a871678dfc22c014f912b4d0b9a1191336b7,
0b2c970d579554d275775981a3717c8daa85f969ebc8151b9da4c5124f526500,
eed5b36a1a6cc9b0e0530990fd04f19b65f9813269f81648f98aa601e60f1152,
2d824950db435f03fffbf010aa0cc002b500ab866dc1e81ec170d7fa6c7aa6b8,
13548528c8c03287e81510c3c6f52efc32637a0bcf2b8bba598ae56c0df4607d
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
f813d8005ea9007e2ba00de9643046ca9d9938db6f4fd9bc7a097935ac53cce4,
d4613c55092f6ec59afdb49b573bc8a6ab210c4bb2b6560f91c3955821260995,
e0217b2fad921ba2e11cf66f8b65e28639a53acddec1584c7c6084b3c9762838
result, different first party:
6af281f233f0c4b74fa9b4ee8656e9cea8492c8467c683453c32bebdad54e8b9,
a41498414c2f8b8f19578f60735011cc419d5c11601a9f5f3c44d5c6a9033f99,
ea7e519d67f5d8feb0013e94a595fd2c039fa0c85ae498d74ab3747fba32d122
unsupported: false, false, false
passed: true, true, true
test failed: 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:
6ee36646e8291ab2158ca6677bd2436d4c4aeffab4f0b81ddb7391eb3622a1e7,
1a2aa6682ff73e519582593871b666319366a910dc40721fe40109a9d2caa430,
b9ee70e2891b8b142057829b9220ff5eaafc487be818d16c60c2a1fad51109b3,
0a92c36bbbf8a4b5823c214a569dc601b665f2e6187c45deac5ec2cb71f282e7,
ebeb098e794a609a3884194393722fbba35d2447a56f17dfd10dd0ce74846a05
result, different first party:
57bd6fc7cdb144054051eb5931ff2b6b002348482e03ea1c92d81d972e7d4c62,
29d9a72a9a84359962094d7b0a297167f2433463cc4bb29ef460c2d4e857bace,
4e3443c604b21069b9da55143d5372132fe551252cc4926678a2dd3e230ea984,
3f06eb49e82412f2dcdd229499d08ac4584c39c6803643eb38229b102ae8486f,
a68c1aed3f70083eb8f9d1c77f374c6b13629211618ad5e846b82471c3793889
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
7e0341b51771912a2f882a4707aa1d5e09b32d5e95bd5082a112a1bb45d3305a,
1f7d1099488b7f7780655ca147268bd598ef4b20c0ff34d72611a19c16886835,
f3b5f450e3762b2915d732db7bb39f223b8a0233fb241e768fab37d162eff66b,
ee00662ad93eb55a5534098105a75cbb9ad9a9f609cc8f0ca8d6522bdac4abb0,
71b1c12c300db38543c4d4158b514b4389044b5851576273a743752b279fa3e0
result, different first party:
3c623463577511344b0ff6a070454608ea79a337c306badd1d872e44f6380e86,
e38095a452aaea9c3557e0747078b86f06c5570c7261adda08c8381eddc7f7f8,
8292e9a1f2757c2bc21cd0af94c2819ea23082a713647e2e9954497e2b415a6b,
a86525181b02a352dacebdc56b31ee9b2eadc5d5ffcba2dcf32977573d4a0105,
a0375bfb095373a9f33b67afdaed9851b6fdd021fda0b43469362fb1a1d765fc
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
66ce8d1b7c8ae841e4a3a0d46243ad5da2da8c620bbd20c7de2e62c5f4eb2602,
6b5d195d6acb7a2617682f90950523c67d0aba2268c42ccd4ffddb6def65d027,
bb80a0280f5ab63de71215abe60ea9cbd75ffec979fe3bb227b7690d35ade73e,
7dfe69b1055f11a71d97b42fcd580da8c6fcffdc44acdfe197179015c5f840b5,
75658ff8ab74c17685ba6c0776a4d8db0f31926850a947f0a7dad9d4a4e20aaa
result, different first party:
7891e12dedddcd8840c9c8417bc858a1cc63002a6f9a8362f7f0f7641df564d2,
546e53d25399f6c248427643ded0dcb143e258a4936637f1947b6756212054ef,
269ece09c28a827e67724cf084dbbc3490b0f7ca12f707ddbe8c425147b1940a,
7b88d29a9c4ecc91b0a231807f6541dbff2fb06eed56f25ec92f771a02d0ce25,
4845a8b134a3a9e5820e455ad2e44fc74525f596d8b6bb470c23e6a55f20d4e1
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }
result, same first party:
b83fa01483e960757b47bcc224f6237f96ce6b4965bd1832175ba821cfae039c,
275b0638f579eddc426727de99ea038d56810a96983c17af2a7c1f91f29820df,
f4c4312bef9fc664dc4727434b72974532e3d6022ce48584333e1c183bbddfac,
705913d2f4c5407a054cca83f7766530296a3fd5c28b9419bd3890d6ee460553,
c7b1c59edcab9844edcb9e88aebbde95fd29b4b58833f41d7aec9178387304c2
result, different first party:
7118c2ea4c9cb34f8b01e13c118867e17788214c34dd9344a49b82ee6eb91cf7,
e583d68be1c6d07e3fa4fc2f1ef56e00b9824ac008c86bea40f96d623230671e,
7ffe6cf2799ee09a883b884f66422da820593e5e2ff44c02bd35abaab9fdebde,
9aa9436a7ea80929d1ef026d7cefed6fcbfe77f764a1582f8b5661f61708caf9,
0caf190a41ddcf44e48eb74dcc9dd5b2d8a36bd9c3f05d5f3f8c84e013a6cfe3
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Navigation testsWhich browsers prevent websites from sharing tracking data when you click on a link?
When you click a hyperlink to navigate your browser from one site to another, certain browser APIs allow the first site to communicate to the second site. These privacy vulnerabilities can be fixed by introducing new limits on how much data is transfered between sites.',
document.referrer
The Referer [sic] request header is a mechanism used by browsers to let a website know where the user is visiting from. This header is inherently tracking users across websites. In recent times, browsers have switched to a policy of trimming a referrer to convey less tracking information, but Referer continues to convey cross-site tracking data by default.
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
sessionStorage
The sessionStorage API is similar to the localStorage API, but it does not persist across tabs or across browser sessions. Nonetheless, it can be used to track users if they navigate from one website to another. This tracking can be thwarted by partitioning sessionStorage between websites.
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
bf74b275-b237-4119-945a-5a08a6e622f6,
983d7a98-4d47-4939-9fde-d29cc857c4f5,
932e9a95-68ef-4e18-9e6a-6888f8984bce,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
f830b9fa-d053-421d-b45e-ee70f920d327,
7a958105-b259-466d-b7c1-7c84dac324d1,
f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
8ec88b82-d540-41d6-8371-402847028e28,
73489d4d-045a-4a14-9a36-c930f96cc1da,
7e9bbe57-0313-457c-94b3-9b03c21e905e,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
174c6491-118a-4f4e-8d3b-a5897bb68365,
b6d43ee5-d8cf-4a09-999e-603533c121fe,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
219ddc64-b2d9-459a-80ad-10bac6d62a02,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
f8ffedfe-aa49-42e0-9767-3241fc941429,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
231555b0-11a9-4057-8e14-df0ea284c964,
a3b647ff-73de-4479-a0a5-526fe1a3fb92,
b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
bce92791-e482-47f6-8faa-eef609817b3a,
3eed10d3-8421-422f-bdae-c0a33ca26848,
8c28c559-9404-41c8-8135-0a2be28ff426,
e4a5f40d-b41a-4715-819b-95f95b7eafaf,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
0c4651b4-95a0-4405-b859-c534de8a5c2e,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
4db065be-12c7-4e4d-a6e0-3ac492a7046f,
6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)
read: () => sessionStorage.getItem("secret")
result, same first party:
0f790d05-2db5-411b-bf10-4b8aeea23a2d,
5b090fae-53dc-463e-bad6-7b057a7774bb,
8e764661-91bb-46a4-92f8-f598653497f0,
e651769f-311b-4111-aa86-57e477e5c1cd,
0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
window.name
The window.name API allows websites to store data that will persist after the user has navigated the tab to a different website. This mechanism could be partitioned so that data is not allowed to persist between websites.
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_bf74b275-b237-4119-945a-5a08a6e622f6,
name_983d7a98-4d47-4939-9fde-d29cc857c4f5,
name_932e9a95-68ef-4e18-9e6a-6888f8984bce,
name_dc56f64c-b0f7-4a26-b659-b15ea9f14a52,
name_11a5432e-af5d-47ac-9573-7b79701cf158
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_3a75dd17-1a72-40d2-bb88-36931a2ef7bd,
name_a81a346b-ed58-4bd5-91ed-92dcf3a9aa29,
name_f830b9fa-d053-421d-b45e-ee70f920d327,
name_7a958105-b259-466d-b7c1-7c84dac324d1,
name_f8325715-9f9d-4b2a-843d-81922950b028
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_8ec88b82-d540-41d6-8371-402847028e28,
name_73489d4d-045a-4a14-9a36-c930f96cc1da,
name_7e9bbe57-0313-457c-94b3-9b03c21e905e,
name_1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
name_d25d4d13-aa43-40f1-bd46-e387c8392518
result, different first party:
name_8ec88b82-d540-41d6-8371-402847028e28,
name_73489d4d-045a-4a14-9a36-c930f96cc1da,
name_7e9bbe57-0313-457c-94b3-9b03c21e905e,
name_1210b9ef-0b3b-4165-bc50-1ba640db2ef2,
name_d25d4d13-aa43-40f1-bd46-e387c8392518
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_2b5e724b-f7ab-4a79-8baa-9d8bdf935766,
name_174c6491-118a-4f4e-8d3b-a5897bb68365,
name_b6d43ee5-d8cf-4a09-999e-603533c121fe,
name_9dd82c6e-a46e-4103-bcfc-0598ac80a0c4,
name_ca2b1281-4542-49ed-b7de-63f29ca49e7d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
name_219ddc64-b2d9-459a-80ad-10bac6d62a02,
name_4151d82f-81a9-4bc6-b52a-ee3626cc0d46
result, different first party:
name_d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046,
name_219ddc64-b2d9-459a-80ad-10bac6d62a02,
name_4151d82f-81a9-4bc6-b52a-ee3626cc0d46
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_f8ffedfe-aa49-42e0-9767-3241fc941429,
name_89c29cbc-cc2c-4b7f-b2de-02bdee3423e2,
name_231555b0-11a9-4057-8e14-df0ea284c964,
name_a3b647ff-73de-4479-a0a5-526fe1a3fb92,
name_b9afa08a-70bb-4887-b8a2-04be55ffe313
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_bce92791-e482-47f6-8faa-eef609817b3a,
name_3eed10d3-8421-422f-bdae-c0a33ca26848,
name_8c28c559-9404-41c8-8135-0a2be28ff426,
name_e4a5f40d-b41a-4715-819b-95f95b7eafaf,
name_0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
result, different first party:
name_bce92791-e482-47f6-8faa-eef609817b3a,
name_3eed10d3-8421-422f-bdae-c0a33ca26848,
name_8c28c559-9404-41c8-8135-0a2be28ff426,
name_e4a5f40d-b41a-4715-819b-95f95b7eafaf,
name_0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_0c4651b4-95a0-4405-b859-c534de8a5c2e,
name_8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd,
name_7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7,
name_4db065be-12c7-4e4d-a6e0-3ac492a7046f,
name_6848c438-def7-48c3-bf4d-d0387b56e58d
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret
read: () => window.name
result, same first party:
name_0f790d05-2db5-411b-bf10-4b8aeea23a2d,
name_5b090fae-53dc-463e-bad6-7b057a7774bb,
name_8e764661-91bb-46a4-92f8-f598653497f0,
name_e651769f-311b-4111-aa86-57e477e5c1cd,
name_0df21732-f557-4c6a-920b-a3f813eaf9ea
result, different first party:
name_0f790d05-2db5-411b-bf10-4b8aeea23a2d,
name_5b090fae-53dc-463e-bad6-7b057a7774bb,
name_8e764661-91bb-46a4-92f8-f598653497f0,
name_e651769f-311b-4111-aa86-57e477e5c1cd,
name_0df21732-f557-4c6a-920b-a3f813eaf9ea
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
HTTPS testsWhich browsers prevent unencrypted network connections?
HTTPS is the protocol that web browsers use to connect securely to websites. When HTTPS is being used, the connection is encrypted so that third parties on the network cannot read content being sent between the server and your browser. In the past, insecure connections were the default and websites would need to actively request that a browser use HTTPS. Now the status quo is shifting, and browser makers are moving toward a world where HTTPS is the default protocol.`
Insecure website warning

            
Passed
passed: true, true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Passed
passed: true, true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Passed
passed: true, true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Passed
passed: true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Passed
passed: true, true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Passed
passed: true, true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Passed
passed: true, true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never 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, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Passed
upgraded: true, true, true
passed: true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, 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, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Passed
upgraded: true, true, true
passed: true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, 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, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true
result: upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Upgradable script
Checks to see if the browser attempts to upgrade an insecure address for an script to HTTPS whenever possible.
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true
result: blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Misc testsWhich browsers provide additional assorted privacy protections?
This category includes tests for the presence of miscellaneous privacy features
ECH enabled
Encrypted Client Hello (ECH) is a new protocol that hides the website you are visiting from third-party network eavesdroppers.
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: encrypted
passed: true, true, true, false, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, 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, true
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false, false, false
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false, false, false
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false, false, false
GPC enabled third-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a visited website not to sell the user's personal data to other parties. This test checks to see if the GPC header is sent to third-party elements on the web page.
Passed
sec-gpc: 1
passed: true, true, true, true, true
Passed
sec-gpc: 1
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false
Passed
sec-gpc: 1
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
Passed
sec-gpc: 1
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
IP address leak
IP addresses can be used to uniquely identify a large percentage of users. A proxy, VPN, or Tor can mask a user's IP address.
Failed
passed: true, true, true, false, false
Passed
passed: true, true, true, true, true
Failed
passed: true, true, true, false, false
Failed
passed: false, true, true, false, false
Failed
passed: true, false, false
Failed
passed: true, false, false, true, false
Failed
passed: true, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
passed: true, false, true, false, true
Stream isolation
Browsers that use Tor can use a different Tor circuit per top-level website.
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Passed
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: false, false, false, false, false
readSameFirstParty:
193.200.229.243,
35.0.127.52,
150.40.127.100,
185.220.101.181,
80.94.92.99
readDifferentFirstParty:
185.246.188.74,
45.84.107.76,
192.108.48.150,
185.220.101.186,
185.220.100.240
passed: true, true, true, true, true
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Passed
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: false, false, false, false, false
readSameFirstParty:
147.90.235.17,
2a0b:f4c2::28,
2a0b:f4c2::9,
147.90.234.159,
2a0f:df00:0:255::202
readDifferentFirstParty:
Error: Unsupported,
2a03:e600:100::10,
2a0d:bbc7::f816:3eff:fe0b:181b,
46.165.243.36,
2a0b:f4c2::8
passed: true, true, true, true, true
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
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').`,
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,true
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,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, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
__hssc
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
__hstc
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
__s
Drip.com email address tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
_hsenc
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
_openstat
Yandex tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
dclid
DoubleClick Click ID (Google)
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
fbclid
Facebook Click Identifier
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
gclid
Google Click Identifier
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
hsCtaTracking
HubSpot tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
mc_eid
Mailchimp Email ID (email recipient's address)
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
mkt_tok
Adobe Marketo tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
ml_subscriber
MailerLite email tracking
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
ml_subscriber_hash
MailerLite email tracking
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
msclkid
Microsoft Click ID
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
oly_anon_id
Omeda marketing 'anonymous' customer id
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
oly_enc_id
Omeda marketing 'known' customer id
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
rb_clickid
Unknown high-entropy tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
s_cid
Adobe Site Catalyst tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
vero_conv
Vero tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
vero_id
Vero tracking parameter
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
wickedid
Wicked Reports e-commerce tracking
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
yclid
Yandex Click ID
Passed
passed: true, true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Failed
value: 6092011535819355
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 6092011535819355
passed: false, false, false, false, false
Tracker content blocking testsWhich browsers block important known tracking scripts and pixels?
When you visit a web page, it frequently has third-party embedded tracking content, such as scripts and tracking pixels. These embedded components spy on you. Some browsers and browser extensions maintain list of tracking companies and block their content from being loaded. This section checks to see if a browser blocks 20 of the largest trackers listed by https://whotracks.me.`
Adobe
Tests whether the browser blocks the page from loading the tracker at https://munchkin.marketo.net/munchkin.js
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: , false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Passed
url: https://munchkin.marketo.net/munchkin.js
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Passed
url: https://munchkin.marketo.net/munchkin.js
Passed
url: https://munchkin.marketo.net/munchkin.js
Passed
url: https://munchkin.marketo.net/munchkin.js
Adobe Audience Manager
Tests whether the browser blocks the page from loading the tracker at https://dpm.demdex.net/ibs
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: , false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Amazon adsystem
Tests whether the browser blocks the page from loading the tracker at https://s.amazon-adsystem.com/dcm
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: , false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: , false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false
AppNexus
Tests whether the browser blocks the page from loading the tracker at https://ib.adnxs.com/px?id=178248&t=1
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false
Bing Ads
Tests whether the browser blocks the page from loading the tracker at https://bat.bing.com/bat.js
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Passed
url: https://bat.bing.com/bat.js
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Passed
url: https://bat.bing.com/bat.js
Failed
url: https://bat.bing.com/bat.js
passed: false
Passed
url: https://bat.bing.com/bat.js
Chartbeat
Tests whether the browser blocks the page from loading the tracker at https://static.chartbeat.com/js/chartbeat.js
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Criteo
Tests whether the browser blocks the page from loading the tracker at https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: , false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: , false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: , false
DoubleClick (Google)
Tests whether the browser blocks the page from loading the tracker at https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: , false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
Facebook tracking
Tests whether the browser blocks the page from loading the tracker at https://connect.facebook.net/en_US/fbevents.js
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Google (third-party ad pixel)
Tests whether the browser blocks the page from loading the tracker at https://www.google.com/pagead/1p-user-list/
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: , false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
Passed
url: https://www.google.com/pagead/1p-user-list/
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false
Google Analytics
Tests whether the browser blocks the page from loading the tracker at https://google-analytics.com/urchin.js
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Passed
url: https://google-analytics.com/urchin.js
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: , false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false
Failed
url: https://google-analytics.com/urchin.js
passed: , false
Google Tag Manager
Tests whether the browser blocks the page from loading the tracker at https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: , false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false
Index Exchange
Tests whether the browser blocks the page from loading the tracker at https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
New Relic
Tests whether the browser blocks the page from loading the tracker at https://js-agent.newrelic.com/nr-1212.min.js
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: , false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: 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, true
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: , false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: , false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: , false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false
Scorecard Research Beacon
Tests whether the browser blocks the page from loading the tracker at https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Taboola
Tests whether the browser blocks the page from loading the tracker at https://trc.taboola.com/futureplc-tomsguide/trc/3/json
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
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, true
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: , false
Failed
url: https://t.co/i/adsct
passed: false, false
Failed
url: https://t.co/i/adsct
passed: false
Yandex Ads
Tests whether the browser blocks the page from loading the tracker at https://yandex.ru/ads/system/header-bidding.js
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
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, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, 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, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, 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, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, 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, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, 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, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Chartbeat
Tests whether the browser stops cookies from static.chartbeat.com from tracking users across websites.
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, 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, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, 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, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Facebook tracking
Tests whether the browser stops cookies from connect.facebook.net from tracking users across websites.
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, 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, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, 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, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, 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, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Index Exchange
Tests whether the browser stops cookies from dsum-sec.casalemedia.com from tracking users across websites.
Passed
passed: true, 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, false
Passed
passed: true, 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, false
Passed
passed: true, 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, false
Passed
passed: true, 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, false
Passed
passed: true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false
Passed
passed: true, 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, false
Passed
passed: true, 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, false
Passed
passed: true, 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, false
Passed
passed: true, 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, 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, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Quantcast
Tests whether the browser stops cookies from pixel.quantserve.com from tracking users across websites.
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, 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, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Taboola
Tests whether the browser stops cookies from trc.taboola.com from tracking users across websites.
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, 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, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Yandex Ads
Tests whether the browser stops cookies from yandex.ru from tracking users across websites.
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Cross-session first-party tracking testsWhich browsers prevent websites from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow websites ("first parties") to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3
result, different session: h2, h2, h2
unsupported: false, false, false
passed: true, true, true
test failed: 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: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_1p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_1p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_1p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_1p,
11a5432e-af5d-47ac-9573-7b79701cf158_1p
result, different session:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_1p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_1p,
f830b9fa-d053-421d-b45e-ee70f920d327_1p,
7a958105-b259-466d-b7c1-7c84dac324d1_1p,
f8325715-9f9d-4b2a-843d-81922950b028_1p
result, different session:
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_1p,
73489d4d-045a-4a14-9a36-c930f96cc1da_1p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_1p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_1p,
d25d4d13-aa43-40f1-bd46-e387c8392518_1p
result, different session:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_1p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_1p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_1p
result, different session:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${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:
f8ffedfe-aa49-42e0-9767-3241fc941429_1p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_1p,
231555b0-11a9-4057-8e14-df0ea284c964_1p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_1p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_1p
result, different session:
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,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_1p,
3eed10d3-8421-422f-bdae-c0a33ca26848_1p,
8c28c559-9404-41c8-8135-0a2be28ff426_1p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_1p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_1p
result, different session:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
0c4651b4-95a0-4405-b859-c534de8a5c2e_1p,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_1p,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_1p,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_1p,
6848c438-def7-48c3-bf4d-d0387b56e58d_1p
result, different session:
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,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_1p,
5b090fae-53dc-463e-bad6-7b057a7774bb_1p,
8e764661-91bb-46a4-92f8-f598653497f0_1p,
e651769f-311b-4111-aa86-57e477e5c1cd_1p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_1p
result, different session:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_1p_http,
983d7a98-4d47-4939-9fde-d29cc857c4f5_1p_http,
932e9a95-68ef-4e18-9e6a-6888f8984bce_1p_http,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_1p_http,
11a5432e-af5d-47ac-9573-7b79701cf158_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_1p_http,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_1p_http,
f830b9fa-d053-421d-b45e-ee70f920d327_1p_http,
7a958105-b259-466d-b7c1-7c84dac324d1_1p_http,
f8325715-9f9d-4b2a-843d-81922950b028_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_1p_http,
73489d4d-045a-4a14-9a36-c930f96cc1da_1p_http,
7e9bbe57-0313-457c-94b3-9b03c21e905e_1p_http,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_1p_http,
d25d4d13-aa43-40f1-bd46-e387c8392518_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p_http,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p_http,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p_http,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p_http,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p_http
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p_http,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p_http,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p_http,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p_http,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_1p_http,
219ddc64-b2d9-459a-80ad-10bac6d62a02_1p_http,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_1p_http
result, different session: , ,
unsupported: false, false, false
passed: true, true, true
test failed: 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(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
f8ffedfe-aa49-42e0-9767-3241fc941429_1p_http,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_1p_http,
231555b0-11a9-4057-8e14-df0ea284c964_1p_http,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_1p_http,
b9afa08a-70bb-4887-b8a2-04be55ffe313_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_1p_http,
3eed10d3-8421-422f-bdae-c0a33ca26848_1p_http,
8c28c559-9404-41c8-8135-0a2be28ff426_1p_http,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_1p_http,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
0c4651b4-95a0-4405-b859-c534de8a5c2e_1p_http,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_1p_http,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_1p_http,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_1p_http,
6848c438-def7-48c3-bf4d-d0387b56e58d_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_1p_http,
5b090fae-53dc-463e-bad6-7b057a7774bb_1p_http,
8e764661-91bb-46a4-92f8-f598653497f0_1p_http,
e651769f-311b-4111-aa86-57e477e5c1cd_1p_http,
0df21732-f557-4c6a-920b-a3f813eaf9ea_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_1p_js,
983d7a98-4d47-4939-9fde-d29cc857c4f5_1p_js,
932e9a95-68ef-4e18-9e6a-6888f8984bce_1p_js,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_1p_js,
11a5432e-af5d-47ac-9573-7b79701cf158_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_1p_js,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_1p_js,
f830b9fa-d053-421d-b45e-ee70f920d327_1p_js,
7a958105-b259-466d-b7c1-7c84dac324d1_1p_js,
f8325715-9f9d-4b2a-843d-81922950b028_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_1p_js,
73489d4d-045a-4a14-9a36-c930f96cc1da_1p_js,
7e9bbe57-0313-457c-94b3-9b03c21e905e_1p_js,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_1p_js,
d25d4d13-aa43-40f1-bd46-e387c8392518_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p_js,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p_js,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p_js,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p_js,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p_js
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p_js,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p_js,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p_js,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p_js,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_1p_js,
219ddc64-b2d9-459a-80ad-10bac6d62a02_1p_js,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_1p_js
result, different session: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
f8ffedfe-aa49-42e0-9767-3241fc941429_1p_js,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_1p_js,
231555b0-11a9-4057-8e14-df0ea284c964_1p_js,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_1p_js,
b9afa08a-70bb-4887-b8a2-04be55ffe313_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_1p_js,
3eed10d3-8421-422f-bdae-c0a33ca26848_1p_js,
8c28c559-9404-41c8-8135-0a2be28ff426_1p_js,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_1p_js,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
0c4651b4-95a0-4405-b859-c534de8a5c2e_1p_js,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_1p_js,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_1p_js,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_1p_js,
6848c438-def7-48c3-bf4d-d0387b56e58d_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_1p_js,
5b090fae-53dc-463e-bad6-7b057a7774bb_1p_js,
8e764661-91bb-46a4-92f8-f598653497f0_1p_js,
e651769f-311b-4111-aa86-57e477e5c1cd_1p_js,
0df21732-f557-4c6a-920b-a3f813eaf9ea_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
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:
bf74b275-b237-4119-945a-5a08a6e622f6_1p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_1p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_1p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_1p,
11a5432e-af5d-47ac-9573-7b79701cf158_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_1p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_1p,
f830b9fa-d053-421d-b45e-ee70f920d327_1p,
7a958105-b259-466d-b7c1-7c84dac324d1_1p,
f8325715-9f9d-4b2a-843d-81922950b028_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
8ec88b82-d540-41d6-8371-402847028e28_1p,
73489d4d-045a-4a14-9a36-c930f96cc1da_1p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_1p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_1p,
d25d4d13-aa43-40f1-bd46-e387c8392518_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (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:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, 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 session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_1p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_1p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_1p
result, different session: , ,
unsupported: false, false, false
passed: true, true, true
test failed: 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 session:
f8ffedfe-aa49-42e0-9767-3241fc941429_1p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_1p,
231555b0-11a9-4057-8e14-df0ea284c964_1p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_1p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
bce92791-e482-47f6-8faa-eef609817b3a_1p,
3eed10d3-8421-422f-bdae-c0a33ca26848_1p,
8c28c559-9404-41c8-8135-0a2be28ff426_1p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_1p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
0c4651b4-95a0-4405-b859-c534de8a5c2e_1p,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_1p,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_1p,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_1p,
6848c438-def7-48c3-bf4d-d0387b56e58d_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_1p,
5b090fae-53dc-463e-bad6-7b057a7774bb_1p,
8e764661-91bb-46a4-92f8-f598653497f0_1p,
e651769f-311b-4111-aa86-57e477e5c1cd_1p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_8306409038489511,
fake_22250690051542432,
fake_01414848393342516,
fake_06536126936581632,
fake_8732617876031092
result, different session:
fake_09597126361576058,
fake_09962123068118345,
fake_30356853637334424,
fake_27447659958018256,
fake_7263769350253766
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_670470985387096,
fake_9796178314463417,
fake_8913029346588881,
fake_7380077867240593,
fake_366054161769632
result, different session:
fake_5943285082190357,
fake_18934316719113808,
fake_4858631060821579,
fake_22558576964979427,
fake_48390235248818736
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3655764201984666,
fake_459070111870856,
fake_3288592841159239,
fake_885779789771175,
fake_4124627360867763
result, different session:
fake_5980836517391797,
fake_8793798028210784,
fake_7976940676464193,
fake_840838358545482,
fake_2537551894886583
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_6721444351392305,
fake_09094522331144428,
fake_9262091254209333,
fake_6717616660192174,
fake_05311628914276856
result, different session:
fake_6721444351392305,
fake_09094522331144428,
fake_9262091254209333,
fake_6717616660192174,
fake_05311628914276856
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_5001254697916864,
fake_8595811856993039,
fake_583933800708472
result, different session:
fake_30727786062706275,
fake_7790605468732794,
fake_18583404319524077
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${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="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_6024830833569685,
fake_5917938040521902,
fake_41333374984145643,
fake_5941798504112465,
fake_5980150645982338
result, different session:
fake_5145833863603064,
fake_3294351846334478,
fake_21303646843324087,
fake_6679288405236956,
fake_023596351653866865
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3640601063610869,
fake_3814289113174283,
fake_12535529441341997,
fake_05932473992732468,
fake_4640071669185033
result, different session:
fake_1358207413816146,
fake_9670588738969572,
fake_2514189316655482,
fake_431193706472341,
fake_2949672666440195
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_6422417172360897,
fake_784667746958349,
fake_18855273693767116,
fake_8051011462705524,
fake_43718302513601537
result, different session:
fake_7606922229747322,
fake_204774358101522,
fake_277252434868168,
fake_6565559615019971,
fake_26289791354818437
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_8339290236548162,
fake_9393995737243637,
fake_5087164408073444,
fake_37461514121546036,
fake_33295960406368397
result, different session:
fake_213954686464489,
fake_42394660116407423,
fake_15590900365701787,
fake_976215278124273,
fake_9953191833640185
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: 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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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: 2, 2, 2, 2, 2
result, different session: 4, 4, 4, 4, 4
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_1p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_1p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_1p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_1p,
11a5432e-af5d-47ac-9573-7b79701cf158_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_1p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_1p,
f830b9fa-d053-421d-b45e-ee70f920d327_1p,
7a958105-b259-466d-b7c1-7c84dac324d1_1p,
f8325715-9f9d-4b2a-843d-81922950b028_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_1p,
73489d4d-045a-4a14-9a36-c930f96cc1da_1p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_1p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_1p,
d25d4d13-aa43-40f1-bd46-e387c8392518_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_1p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_1p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_1p
result, different session: undefined
unsupported: false, false, false
passed: true, true, true
test failed: 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:
f8ffedfe-aa49-42e0-9767-3241fc941429_1p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_1p,
231555b0-11a9-4057-8e14-df0ea284c964_1p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_1p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_1p,
3eed10d3-8421-422f-bdae-c0a33ca26848_1p,
8c28c559-9404-41c8-8135-0a2be28ff426_1p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_1p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
0c4651b4-95a0-4405-b859-c534de8a5c2e_1p,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_1p,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_1p,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_1p,
6848c438-def7-48c3-bf4d-d0387b56e58d_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_1p,
5b090fae-53dc-463e-bad6-7b057a7774bb_1p,
8e764661-91bb-46a4-92f8-f598653497f0_1p,
e651769f-311b-4111-aa86-57e477e5c1cd_1p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_1p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_1p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_1p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_1p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_1p,
11a5432e-af5d-47ac-9573-7b79701cf158_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_1p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_1p,
f830b9fa-d053-421d-b45e-ee70f920d327_1p,
7a958105-b259-466d-b7c1-7c84dac324d1_1p,
f8325715-9f9d-4b2a-843d-81922950b028_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_1p,
73489d4d-045a-4a14-9a36-c930f96cc1da_1p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_1p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_1p,
d25d4d13-aa43-40f1-bd46-e387c8392518_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_1p,
174c6491-118a-4f4e-8d3b-a5897bb68365_1p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_1p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_1p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_1p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_1p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_1p
result, different session: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
f8ffedfe-aa49-42e0-9767-3241fc941429_1p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_1p,
231555b0-11a9-4057-8e14-df0ea284c964_1p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_1p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_1p,
3eed10d3-8421-422f-bdae-c0a33ca26848_1p,
8c28c559-9404-41c8-8135-0a2be28ff426_1p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_1p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0c4651b4-95a0-4405-b859-c534de8a5c2e_1p,
8411fd8e-6ec1-49e2-a5d2-8a72c8e807cd_1p,
7b026aa2-8ae1-4839-9bf4-0f8f0ba12ea7_1p,
4db065be-12c7-4e4d-a6e0-3ac492a7046f_1p,
6848c438-def7-48c3-bf4d-d0387b56e58d_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_1p,
5b090fae-53dc-463e-bad6-7b057a7774bb_1p,
8e764661-91bb-46a4-92f8-f598653497f0_1p,
e651769f-311b-4111-aa86-57e477e5c1cd_1p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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 session: 1, 1, 1
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: 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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Cross-session third-party tracking testsWhich browsers prevent third-party trackers from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow third-party trackers to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
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: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3
result, different session: h2, h2, h2
unsupported: false, false, false
passed: true, true, true
test failed: 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: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h2, h2, h2, h2, h2
result, different session: h2, h2, h2, h2, h2
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }
read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }
result, same session: h3, h3, h3, h3, h3
result, different session: h2, h2, h2, h2, h2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_3p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_3p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_3p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_3p,
11a5432e-af5d-47ac-9573-7b79701cf158_3p
result, different session:
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_3p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_3p,
f830b9fa-d053-421d-b45e-ee70f920d327_3p,
7a958105-b259-466d-b7c1-7c84dac324d1_3p,
f8325715-9f9d-4b2a-843d-81922950b028_3p
result, different session:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_3p,
73489d4d-045a-4a14-9a36-c930f96cc1da_3p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_3p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_3p,
d25d4d13-aa43-40f1-bd46-e387c8392518_3p
result, different session:
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_3p,
174c6491-118a-4f4e-8d3b-a5897bb68365_3p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_3p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_3p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_3p
result, different session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_3p,
174c6491-118a-4f4e-8d3b-a5897bb68365_3p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_3p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_3p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_3p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_3p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_3p
result, different session:
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
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
f8ffedfe-aa49-42e0-9767-3241fc941429_3p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_3p,
231555b0-11a9-4057-8e14-df0ea284c964_3p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_3p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_3p
result, different session:
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_3p,
3eed10d3-8421-422f-bdae-c0a33ca26848_3p,
8c28c559-9404-41c8-8135-0a2be28ff426_3p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_3p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_3p
result, different session:
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
result, different session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_3p,
5b090fae-53dc-463e-bad6-7b057a7774bb_3p,
8e764661-91bb-46a4-92f8-f598653497f0_3p,
e651769f-311b-4111-aa86-57e477e5c1cd_3p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_3p
result, different session:
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'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_3p_http,
983d7a98-4d47-4939-9fde-d29cc857c4f5_3p_http,
932e9a95-68ef-4e18-9e6a-6888f8984bce_3p_http,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_3p_http,
11a5432e-af5d-47ac-9573-7b79701cf158_3p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_3p_http,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_3p_http,
f830b9fa-d053-421d-b45e-ee70f920d327_3p_http,
7a958105-b259-466d-b7c1-7c84dac324d1_3p_http,
f8325715-9f9d-4b2a-843d-81922950b028_3p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , ,
result, different session: , ,
unsupported: true, true, true
passed: undefined
test failed: false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${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:
f8ffedfe-aa49-42e0-9767-3241fc941429_3p_http,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_3p_http,
231555b0-11a9-4057-8e14-df0ea284c964_3p_http,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_3p_http,
b9afa08a-70bb-4887-b8a2-04be55ffe313_3p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_3p_js,
983d7a98-4d47-4939-9fde-d29cc857c4f5_3p_js,
932e9a95-68ef-4e18-9e6a-6888f8984bce_3p_js,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_3p_js,
11a5432e-af5d-47ac-9573-7b79701cf158_3p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_3p_js,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_3p_js,
f830b9fa-d053-421d-b45e-ee70f920d327_3p_js,
7a958105-b259-466d-b7c1-7c84dac324d1_3p_js,
f8325715-9f9d-4b2a-843d-81922950b028_3p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , ,
result, different session: , ,
unsupported: true, true, true
passed: undefined
test failed: false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
f8ffedfe-aa49-42e0-9767-3241fc941429_3p_js,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_3p_js,
231555b0-11a9-4057-8e14-df0ea284c964_3p_js,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_3p_js,
b9afa08a-70bb-4887-b8a2-04be55ffe313_3p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
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:
bf74b275-b237-4119-945a-5a08a6e622f6_3p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_3p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_3p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_3p,
11a5432e-af5d-47ac-9573-7b79701cf158_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (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:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_3p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_3p,
f830b9fa-d053-421d-b45e-ee70f920d327_3p,
7a958105-b259-466d-b7c1-7c84dac324d1_3p,
f8325715-9f9d-4b2a-843d-81922950b028_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session: , ,
result, different session: , ,
unsupported: true, true, true
passed: undefined
test failed: 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 session:
f8ffedfe-aa49-42e0-9767-3241fc941429_3p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_3p,
231555b0-11a9-4057-8e14-df0ea284c964_3p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_3p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }
read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_7626429520256794,
fake_8784317208717367,
fake_4743878129547634,
fake_46109871393361246,
fake_11314099988673987
result, different session:
fake_7311155575208435,
fake_32262307894747244,
fake_958136519463475,
fake_8111054492578416,
fake_69947386736614
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_9426584411557632,
fake_0758192071296171,
fake_1427408121155609,
fake_4451923822588324,
fake_2032061783011414
result, different session:
fake_8260329410098031,
fake_01774890098092685,
fake_5425578854036035,
fake_5232645668959803,
fake_17233706681446614
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_4039499582066428,
fake_4665317481993678,
fake_11595650143466218,
fake_9660250972931796,
fake_7102197541828488
result, different session:
fake_5418239460774228,
fake_9621205238746522,
fake_2609426148213725,
fake_32845166400238,
fake_7971794681293736
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_20110745037034472,
fake_7493569777936164,
fake_8425928380540133,
fake_6107990861255783,
fake_18333028480807134
result, different session:
fake_20110745037034472,
fake_7493569777936164,
fake_8425928380540133,
fake_6107990861255783,
fake_18333028480807134
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_5023485842557933,
fake_6441933219776215,
fake_23778787349489727
result, different session:
fake_2957661501832778,
fake_13664809303203795,
fake_9992766733897633
unsupported: false, false, false
passed: true, true, true
test failed: 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_4740363084901429,
fake_9108494660201425,
fake_2879293850274467,
fake_6288886125164606,
fake_32506799538577846
result, different session:
fake_3001220973234793,
fake_6647674687460443,
fake_14723045171797744,
fake_02313759785959868,
fake_3015338695968228
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_8109879484163856,
fake_5779270492733202,
fake_09231229355320103,
fake_5014648705895004,
fake_2463598515052452
result, different session:
fake_5424095506114064,
fake_879736929369973,
fake_8815414710446128,
fake_5958259216416479,
fake_6708812679199294
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_8361819844631124,
fake_7470486468028348,
fake_20036834507237655,
fake_36697980232023575,
fake_8025467132940376
result, different session:
fake_7727448619748682,
fake_7168754887761632,
fake_3855676576677307,
fake_09477498820634267,
fake_6517063399349101
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }
read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }
result, same session:
fake_3217794506586158,
fake_5899815329074862,
fake_7516837420521307,
fake_0694786164671568,
fake_09929211366223356
result, different session:
fake_7929918204140962,
fake_2874976615061924,
fake_1494011154470829,
fake_8031330724163372,
fake_7454893045395541
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: 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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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: 2, 2, 2, 2, 2
result, different session: 4, 4, 4, 4, 4
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }
read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }
read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })
read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })
read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_3p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_3p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_3p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_3p,
11a5432e-af5d-47ac-9573-7b79701cf158_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_3p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_3p,
f830b9fa-d053-421d-b45e-ee70f920d327_3p,
7a958105-b259-466d-b7c1-7c84dac324d1_3p,
f8325715-9f9d-4b2a-843d-81922950b028_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_3p,
73489d4d-045a-4a14-9a36-c930f96cc1da_3p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_3p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_3p,
d25d4d13-aa43-40f1-bd46-e387c8392518_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_3p,
174c6491-118a-4f4e-8d3b-a5897bb68365_3p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_3p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_3p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_3p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_3p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_3p
result, different session: undefined
unsupported: false, false, false
passed: true, true, true
test failed: 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:
f8ffedfe-aa49-42e0-9767-3241fc941429_3p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_3p,
231555b0-11a9-4057-8e14-df0ea284c964_3p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_3p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_3p,
3eed10d3-8421-422f-bdae-c0a33ca26848_3p,
8c28c559-9404-41c8-8135-0a2be28ff426_3p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_3p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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,
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,
Error: IDBFactory.open: The operation is insecure
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }
read: () => IdbKeyVal.get("secret")
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_3p,
5b090fae-53dc-463e-bad6-7b057a7774bb_3p,
8e764661-91bb-46a4-92f8-f598653497f0_3p,
e651769f-311b-4111-aa86-57e477e5c1cd_3p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_3p
result, different session: undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
bf74b275-b237-4119-945a-5a08a6e622f6_3p,
983d7a98-4d47-4939-9fde-d29cc857c4f5_3p,
932e9a95-68ef-4e18-9e6a-6888f8984bce_3p,
dc56f64c-b0f7-4a26-b659-b15ea9f14a52_3p,
11a5432e-af5d-47ac-9573-7b79701cf158_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
3a75dd17-1a72-40d2-bb88-36931a2ef7bd_3p,
a81a346b-ed58-4bd5-91ed-92dcf3a9aa29_3p,
f830b9fa-d053-421d-b45e-ee70f920d327_3p,
7a958105-b259-466d-b7c1-7c84dac324d1_3p,
f8325715-9f9d-4b2a-843d-81922950b028_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
8ec88b82-d540-41d6-8371-402847028e28_3p,
73489d4d-045a-4a14-9a36-c930f96cc1da_3p,
7e9bbe57-0313-457c-94b3-9b03c21e905e_3p,
1210b9ef-0b3b-4165-bc50-1ba640db2ef2_3p,
d25d4d13-aa43-40f1-bd46-e387c8392518_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
2b5e724b-f7ab-4a79-8baa-9d8bdf935766_3p,
174c6491-118a-4f4e-8d3b-a5897bb68365_3p,
b6d43ee5-d8cf-4a09-999e-603533c121fe_3p,
9dd82c6e-a46e-4103-bcfc-0598ac80a0c4_3p,
ca2b1281-4542-49ed-b7de-63f29ca49e7d_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
d9a0a0b6-64d4-4f59-85d2-ac21e0dbf046_3p,
219ddc64-b2d9-459a-80ad-10bac6d62a02_3p,
4151d82f-81a9-4bc6-b52a-ee3626cc0d46_3p
result, different session: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
f8ffedfe-aa49-42e0-9767-3241fc941429_3p,
89c29cbc-cc2c-4b7f-b2de-02bdee3423e2_3p,
231555b0-11a9-4057-8e14-df0ea284c964_3p,
a3b647ff-73de-4479-a0a5-526fe1a3fb92_3p,
b9afa08a-70bb-4887-b8a2-04be55ffe313_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
bce92791-e482-47f6-8faa-eef609817b3a_3p,
3eed10d3-8421-422f-bdae-c0a33ca26848_3p,
8c28c559-9404-41c8-8135-0a2be28ff426_3p,
e4a5f40d-b41a-4715-819b-95f95b7eafaf_3p,
0bc5c5c1-6aa8-4c3c-ad2c-bbd03f66a0c1_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, 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.,
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.,
Error: The operation is insecure.
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)
read: () => localStorage.getItem("secret")
result, same session:
0f790d05-2db5-411b-bf10-4b8aeea23a2d_3p,
5b090fae-53dc-463e-bad6-7b057a7774bb_3p,
8e764661-91bb-46a4-92f8-f598653497f0_3p,
e651769f-311b-4111-aa86-57e477e5c1cd_3p,
0df21732-f557-4c6a-920b-a3f813eaf9ea_3p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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 session: 1, 1, 1
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: 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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }
read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }
result, same session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different session:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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 session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })
read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 1, 1, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
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
result, different session: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }
read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }
result, same session: 1, 1, 1, 1, 1
result, different session: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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.
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true
leak detected: false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Location: China
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in China.
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true
leak detected: false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, 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, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, 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, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true
leak detected: false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, 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.
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false
leak detected: true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true