Desktop Browsers

(default settings)
brave logo
brave
1.62
chrome logo
chrome
121.0
edge logo
edge
121.0
firefox logo
firefox
122.0
librewolf logo
librewolf
122.0-2
mullvad logo
mullvad
13.0
opera logo
opera
106.0
safari logo
safari
17.3
tor logo
tor
13.0
ungoogled logo
ungoogled
121.0
vivaldi logo
vivaldi
6.5
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

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

result, different first party: h2, h2, h2, h2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same first party: h3, h3, h3

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

result, different first party: h2, h2, h2, h2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same first party: h3, h3, h3, h3, 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

result, different first party: h2, h2, h2, h2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: h3, h3, h3, h3, h3

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: 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
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same first party: h3, h3, h3, h3

result, different first party: h2, h2, h2, h2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
blob
A 'blob URL' is a local reference to some raw data. Trackers can use a blob URL to share data between websites.
              
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

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
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

result, different first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

unsupported: false, false, false

passed: false, false, false

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: 
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
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: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

result, different first party: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: (secret) => {
      try {
        let blobURL = URL.createObjectURL(new Blob([secret]));
        fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async (secret) => {
      let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
      let result = await response.json();
      let blobUrl = decodeURIComponent(result.blobUrl);
      let blobResponse = await fetch(blobUrl);
      return blobResponse.text();
    }

result, same first party: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
BroadcastChannel
A BroadcastChannel is designed to send messages between tabs. In some browsers it can be used for cross-site communication and tracking.
              
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: 
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => {
      try {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data === "request") {
            bc.postMessage(secret);
          }
        };
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () =>
      new Promise((resolve, reject) => {
        let bc = new BroadcastChannel("secrets");
        bc.onmessage = (event) => {
          if (event.data !== "request") {
            resolve(event.data);
          }
        };
        bc.postMessage("request");
        setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000);
      })

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
              
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: 
Error: Failed to execute 'open' on 'CacheStorage': An attempt was made to break through the security policy of the user agent.,
Error: Failed to execute 'open' on 'CacheStorage': An attempt was made to break through the security policy of the user agent.,
Error: Failed to execute 'open' on 'CacheStorage': An attempt was made to break through the security policy of the user agent.

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

result, different first party: 
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined

unsupported: false, false, false, false, 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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: 
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
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 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.

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: 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 first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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
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 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.

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: 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 first party: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
              
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5_http,
96e35e8b-83e3-40bb-90b2-81254058442a_http,
42faff19-a4d5-4440-8137-9f83240f2c24_http

result, different first party: , , 

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_http,
8d0209a9-77a1-45f6-a4b5-a9584894699d_http,
1d5f5063-ff3c-4279-be0f-6dfede562600_http,
376bcea2-2ac1-40b3-918e-4e8e864e1535_http

result, different first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_http,
8d0209a9-77a1-45f6-a4b5-a9584894699d_http,
1d5f5063-ff3c-4279-be0f-6dfede562600_http,
376bcea2-2ac1-40b3-918e-4e8e864e1535_http

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_http,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_http,
b5df093b-83a0-4796-9013-592159fae4bb_http

result, different first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_http,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_http,
b5df093b-83a0-4796-9013-592159fae4bb_http

unsupported: false, false, false

passed: false, false, false

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612_http,
960952de-fbd6-4278-85f0-c562117c1b2c_http,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_http,
3d908420-2f5e-44f6-a751-14480e05325b_http,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16_http,
c7a7c812-94af-406a-b0f4-a3e96ac970f5_http,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd_http,
266fad2e-6322-4934-8fa0-1414fb15087c_http

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51_http,
670402ab-7c8e-498e-a2fc-412775b7bcd8_http,
bdd23153-2777-4dfe-839b-53c83748e0a7_http,
541a2489-bb99-46aa-a401-167bf5f8f9e3_http,
1c747676-e705-48b0-b808-613ddbd9f42e_http

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: 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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_http,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_http,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_http,
337c4058-1e91-4e08-980e-c55996dae7a5_http

result, different first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_http,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_http,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_http,
337c4058-1e91-4e08-980e-c55996dae7a5_http

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4_http,
1eca2786-e863-40a4-aa45-8b3d77537dd3_http,
bca01b74-5bc7-4b7a-9e37-c83bb8833959_http,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5_http,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3_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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020_http,
5bac69f9-2e81-4d64-8833-116de9ad280b_http,
9b9b853c-fb5e-4113-9bc7-5324994c3313_http,
61bcf04a-8b1c-4354-b756-c6aded26aa47_http,
6958e9c5-1694-469a-88ea-e72d4b5bb2af_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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_http,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_http,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_http,
b3a4e711-f75e-4c0b-be54-f0882233165b_http,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_http

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: 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: 
f2f031ec-3fda-40df-bf47-ba901a076318_http,
68136c5b-37e8-4e21-ae51-67439b43e4c0_http,
1b14187b-5343-4343-9cbe-a884e4b82b0a_http,
76037bad-07bc-410e-a311-7fbf2b5787a5_http

result, different first party: 
f2f031ec-3fda-40df-bf47-ba901a076318_http,
68136c5b-37e8-4e21-ae51-67439b43e4c0_http,
1b14187b-5343-4343-9cbe-a884e4b82b0a_http,
76037bad-07bc-410e-a311-7fbf2b5787a5_http

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
              
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5_js,
96e35e8b-83e3-40bb-90b2-81254058442a_js,
42faff19-a4d5-4440-8137-9f83240f2c24_js

result, different first party: , , 

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_js,
8d0209a9-77a1-45f6-a4b5-a9584894699d_js,
1d5f5063-ff3c-4279-be0f-6dfede562600_js,
376bcea2-2ac1-40b3-918e-4e8e864e1535_js

result, different first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_js,
8d0209a9-77a1-45f6-a4b5-a9584894699d_js,
1d5f5063-ff3c-4279-be0f-6dfede562600_js,
376bcea2-2ac1-40b3-918e-4e8e864e1535_js

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_js,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_js,
b5df093b-83a0-4796-9013-592159fae4bb_js

result, different first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_js,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_js,
b5df093b-83a0-4796-9013-592159fae4bb_js

unsupported: false, false, false

passed: false, false, false

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612_js,
960952de-fbd6-4278-85f0-c562117c1b2c_js,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_js,
3d908420-2f5e-44f6-a751-14480e05325b_js,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16_js,
c7a7c812-94af-406a-b0f4-a3e96ac970f5_js,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd_js,
266fad2e-6322-4934-8fa0-1414fb15087c_js

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51_js,
670402ab-7c8e-498e-a2fc-412775b7bcd8_js,
bdd23153-2777-4dfe-839b-53c83748e0a7_js,
541a2489-bb99-46aa-a401-167bf5f8f9e3_js,
1c747676-e705-48b0-b808-613ddbd9f42e_js

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) => {
      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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_js,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_js,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_js,
337c4058-1e91-4e08-980e-c55996dae7a5_js

result, different first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_js,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_js,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_js,
337c4058-1e91-4e08-980e-c55996dae7a5_js

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4_js,
1eca2786-e863-40a4-aa45-8b3d77537dd3_js,
bca01b74-5bc7-4b7a-9e37-c83bb8833959_js,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5_js,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3_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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020_js,
5bac69f9-2e81-4d64-8833-116de9ad280b_js,
9b9b853c-fb5e-4113-9bc7-5324994c3313_js,
61bcf04a-8b1c-4354-b756-c6aded26aa47_js,
6958e9c5-1694-469a-88ea-e72d4b5bb2af_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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_js,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_js,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_js,
b3a4e711-f75e-4c0b-be54-f0882233165b_js,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_js

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) => {
      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: 
f2f031ec-3fda-40df-bf47-ba901a076318_js,
68136c5b-37e8-4e21-ae51-67439b43e4c0_js,
1b14187b-5343-4343-9cbe-a884e4b82b0a_js,
76037bad-07bc-410e-a311-7fbf2b5787a5_js

result, different first party: 
f2f031ec-3fda-40df-bf47-ba901a076318_js,
68136c5b-37e8-4e21-ae51-67439b43e4c0_js,
1b14187b-5343-4343-9cbe-a884e4b82b0a_js,
76037bad-07bc-410e-a311-7fbf2b5787a5_js

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
              
Passed
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: , , 

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Failed
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

result, different first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true

passed: undefined

test failed: false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
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
Failed
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: (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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
              
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same first party: 
fake_6020768407619022,
fake_967571041631847,
fake_7884303364553393

result, different first party: 
fake_9756757959883808,
fake_018731155224875007,
fake_17649606331022438

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 first party: 
fake_31060690982189265,
fake_9292942758597011,
fake_3714959811832965,
fake_6309976047739552

result, different first party: 
fake_6305585493038648,
fake_9714470386316829,
fake_6965460235785903,
fake_10662361919039687

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same first party: 
fake_9842469053045719,
fake_7784625006657113,
fake_06860184812721437

result, different first party: 
fake_8866272931000634,
fake_026045851726350877,
fake_03892901608960475

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 first party: 
fake_13281691867105727,
fake_14741246766148053,
fake_47468617038325744,
fake_01882102415868303,
fake_5317761583642002

result, different first party: 
fake_9525346306453288,
fake_8797937525905513,
fake_851322760599788,
fake_5679983940210165,
fake_5032398925693196

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_3641584396620807,
fake_27071774629717993,
fake_4364111062777485,
fake_7284335440885927

result, different first party: 
fake_9952998656385459,
fake_6021587415392315,
fake_7937354466915401,
fake_050780517967628835

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same first party: 
fake_1285657739103494,
fake_31600565990048124,
fake_34769632569721254,
fake_2928636693872133,
fake_35571878369787857

result, different first party: 
fake_07787931526815095,
fake_17886353402203303,
fake_29680936147454884,
fake_13764691011957564,
fake_2212856035084434

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_3073710795732312,
fake_1996283304797113,
fake_6485757714975056,
fake_11185691091016503

result, different first party: 
fake_8596411204921388,
fake_4361349401766812,
fake_18369021257826335,
fake_4129111260073992

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same first party: 
fake_9750478652735111,
fake_3141453131541232,
fake_6106366512228747,
fake_33738025827498475,
fake_787729349362021

result, different first party: 
fake_49214760436388816,
fake_9853144711421633,
fake_11154496682876913,
fake_99410641099058,
fake_8215008203861978

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_174684674071776,
fake_01909946432663756,
fake_7923114636332951,
fake_019861707718758614,
fake_5431696878721657

result, different first party: 
fake_32912788858362085,
fake_4602117323438393,
fake_8674066573347947,
fake_35509984510932613,
fake_292600001358438

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_6990868068414948,
fake_8243721522158378,
fake_3226874527842778,
fake_13758470658069077,
fake_3785785621096036

result, different first party: 
fake_6296053618776056,
fake_5198578484804812,
fake_638711493832189,
fake_6946478289798454,
fake_5044550118125235

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_4272297221582959,
fake_8017125925150341,
fake_3642692067047113,
fake_5854246853960934

result, different first party: 
fake_24621668086563298,
fake_8100757494453077,
fake_35076590798456153,
fake_7980464691794771

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
              
Passed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same first party: 1, 1, 1

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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same first party: 1, 1, 1

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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 3, 3, 3, 3

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
              
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1

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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1

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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
              
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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 style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 2, 2, 2, 2, 2

result, different first party: 3, 3, 3, 3, 3

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 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
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
getDirectory
navigator.storage.getDirectory exposes a location for storing files to web content. In some cases, these files may be shared across tabs.
              
Passed
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false

passed: true, true, true

test failed: 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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false

passed: true, true, true

test failed: 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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

result, same first party: 
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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

result, same first party: , , , , 

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt", { create: true });
        const stream = await fileHandle.createWritable();
        await stream.write(secret);
        await stream.close();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      try {
        const root = await navigator.storage.getDirectory();
        const fileHandle = await root.getFileHandle("secret.txt");
        const file = await fileHandle.getFile();
        return file.text();
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

result, same first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
H1 connection
HTTP/1.x are the classic web connection protocols. If these connections are re-used across websites, they can be used to track users.
              
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: , , Error: Failed to fetch, 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
H2 connection
HTTP/2 is a web connection protocol introduced in 2015. Some browsers re-use HTTP/2 connections across websites and can thus be used to track users.
              
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"});
    }

read: async () => {
      let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"});
      return await response.text();
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
H3 connection
HTTP/3 is a new standard HTTP connection protocol, still in draft but widely supported by browsers. If it is not partitioned, it can be used to track users across websites.
              
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }

result, same first party: 
1c5f4e397c4c17b456f2df89ee226a7b,
2da5c7af52b940d4f559869efe1942bb,
e16f02c3215c581424e07adf326dadba

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: 
745d8f5cd8ae50b9632ac1e141d71bff,
d8c1b5b391a6eeb0952b13cc64d85225,
05f323a8fa526f51320a6a75daa72ad2,
fe7fe174aae0a38e7afb534332c10352

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }

result, same first party: 
b036bc8a8b3fa78484ee4dd1b18550ec,
cbba92bc9edb51c54a44f950e52302d3,
83a0abc5c610301bfb89d2e0896bfb9d

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: 
f4ed4e301ae52a9f93bbac65f279c1b8,
6e24fdac755ceeef33c38c03cbdf7436,
51243bfe25fc814fb78d15d65c72b73f,
7889fb9d2794cfa30bb753aece993e79,
75dfbef741a0ad9fd552cf6c1c1a1b22

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: 
6c4c58979cc0afbaa4fc654fb57ed44e,
ab2f965582edefaf49e7838916479aa4,
233d62173e5f745d0772201bf704f65c,
632d2770ce4e2c952e7ca7358635415c

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }

result, same first party: 
5215ad6a3bcc00303b7ad6bba60e0b33,
6c58dc760bfad6a8b0a4df99ea713cbc,
63b1aaee212298ceb6dd00d53d1c9be1,
76271015c72b31f5ac834a81a0d24050,
5e1c653b4370d0372db7dff270e2d78b

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: 
79bd841075af2f4080c75ec20afdb1ff,
bbe294304d117b911f4da5f13a50758a,
f5b9ca15465d2b2a19c4ae080d235c23,
c46f415b8f437193e9d42dbb3a0e2908

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }

result, same first party: 
379cf31bb3335aca2563d77d2990b5b3,
,
30825ecff8f359f8a9efc3fa0c344f9d,
5650bc726f30b038f7d3c60ac9af926a,
f20eeba5b5f649592cd11c4477a0004a

result, different first party: 
d3ff62d6c1cd45f69d55751533df7d1d,
055367ca5b9fc84392c804269bb002b3,
2a3dbd0e087d96b5a3f75ddca6628095,
228909ebddc99dd18f5a3061ec54419e,
99efb3314699640c5e776c698851d3eb

unsupported: false, true, false, false, false

passed: true, true, true, true

test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }

result, same first party: , , , , 

result, different first party: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
      for (let i = 0; i<3; ++i) {
        await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
        await sleepMs(500);
      }
      // Are we now connecting over h3?
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"});
      let text = await response.text();
      // Empty response text indicates we are not connecting over h3:
      if (text.trim() === "") {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`);
      return await response.text();
    }

result, same first party: 
94ae52b38b6b8dd2f851fad580004c01,
86bbf7295175fd356f82f7cb2187ed77,
a03dcefbdf5ad8e3a3ddccf0c80c032c,
0f1d8797a5450907c38f1f1af55dfdc7,
84edef4a9161974c2b06a8172b948a77

result, different first party: , , , 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: 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: 
d7998b1627bf4b731ae1b3e36e4a644a,
256847e2deee901466148f46de996e4e,
e26b5d475b9e5e1beb680e55fd8240d5,
662a05b13efd9703ca19d120749a48ee

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
HSTS cache
The HTTP Strict-Transport-Security response header allows a website to signal that it should only be accessed via HTTPS. The browser remembers this directive in a database, but if this database is not partitioned, then it can be used to track users across websites."
              
Passed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested

result, different first party: Used http, Used http, Used http

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Failed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested, not tested

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false

passed: false, false, false

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

unsupported: , , , 

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: null

read: null

result, same first party: , , , , 

result, different first party: 
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
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

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested, not tested, 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
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
Failed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested, not tested

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
HSTS cache (fetch)
The HTTP Strict-Transport-Security response header allows a website to signal that it should only be accessed via HTTPS. The browser remembers this directive in a database, but if this database is not partitioned, then it can be used to track users across websites."
              
Passed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested

result, different first party: Used http, Used http, Used http

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Failed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested, not tested

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false

passed: false, false, false

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

unsupported: , , , 

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: null

read: null

result, same first party: , , , , 

result, different first party: 
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
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

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested, not tested, 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
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
Failed
write: set HSTS flag

read: read HSTS flag

result, same first party: not tested, not tested, not tested, not tested

result, different first party: 
Upgraded to https,
Upgraded to https,
Upgraded to https,
Upgraded to https

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
              
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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, 2

result, different first party: 2, 2, 2, 2, 3

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
              
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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 img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 2, 2, 2, 2, 2

result, different first party: 3, 3, 3, 3, 3

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 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
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
              
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: 
Error: The user denied permission to access the database.,
Error: The user denied permission to access the database.,
Error: The user denied permission to access the database.

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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 (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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 (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same first party: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
              
Passed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
locks
navigator.locks (only supported in some browsers) allows scripts on multiple tabs to coordinate. If this API is not partitioned, it can be used for cross-site tracking.
              
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: 
Error: The request was denied.,
Error: The request was denied.,
Error: The request was denied.

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: 
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context,
Error: LockManager.query: query() is not allowed in this context

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      if (navigator.locks) {
        navigator.locks.request(key, lock => new Promise((f,r) => {}));
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].clientId;
      } else {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      if (navigator.locks) {
        let queryResult = await navigator.locks.query();
        return queryResult.held[0].name;
      }
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
              
Passed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 1, 1, 1

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 link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 1, 1, 1

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 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
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true

passed: undefined

test failed: false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
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
Passed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different first party: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
script cache
Caching of scripts in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
              
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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 script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1

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 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 2, 2, 2, 2, 2

result, different first party: 3, 3, 3, 3, 3

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 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
Passed
write: (key) => new Promise((resolve, reject) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      script.addEventListener("load", () => resolve(key), {once: true});
      script.src = testURI("resource", "script", key);
    })

read: async (key) => {
      let script = document.createElement("script");
      document.body.appendChild(script);
      let scriptLoadPromise = new Promise((resolve, reject) => {
        script.addEventListener("load", resolve, {once: true});
      });
      script.src = testURI("resource", "script", key);
      await scriptLoadPromise;
      let response = await fetch(
        testURI("ctr", "script", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
ServiceWorker
The ServiceWorker API allows websites to run code in the background and store content in the browser for offline use. If a ServiceWorker can be accessed from multiple websites, it can be abused to track users across sites.
              
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->


result, different first party: 
Error: Failed to register a ServiceWorker for scope ('https://test-pages.privacytests2.org/') with script ('https://test-pages.privacytests2.org/serviceWorker.js'): The user denied permission to use Service Worker.,
Error: Failed to register a ServiceWorker for scope ('https://test-pages.privacytests2.org/') with script ('https://test-pages.privacytests2.org/serviceWorker.js'): The user denied permission to use Service Worker.,
Error: Failed to register a ServiceWorker for scope ('https://test-pages.privacytests2.org/') with script ('https://test-pages.privacytests2.org/serviceWorker.js'): The user denied permission to use Service Worker.

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->


result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->


result, different first party: , , 

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: , , , , 

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: , , , 

result, different first party: , , , 

unsupported: false, false, false, false

passed: undefined

test failed: true, true, true, true
Unsupported
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined

result, different first party: 
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->


result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: , , , , 

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Unsupported
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined

result, different first party: 
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined,
Error: navigator.serviceWorker is undefined

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->


result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Passed
write: async (key) => {
      if (!navigator.serviceWorker) {
        throw new Error("Unsupported");
      }
      let registration = await navigator.serviceWorker.register(
        'serviceWorker.js');
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      await fetch(`serviceworker-write?secret=${key}`);
    }

read: async () => {
      console.log("trying to register the serviceworker now...");
      const registration = await Promise.race([
        navigator.serviceWorker.register('serviceWorker.js'),
        sleepMs(500)
      ]);
      if (registration === undefined) {
        // We timed out or otherwise failed.
        throw new Error("ServiceWorker registration failed");
      }
      console.log(registration);
      await navigator.serviceWorker.ready;
      console.log("service worker ready");
      await sleepMs(100);
      let response = await fetch("serviceworker-read");
      return await response.text();
    }

result, same first party: 
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
,
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>nginx/1.18.0 (Ubuntu)</center>
</body>
</html>
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->
<!-- a padding to disable MSIE and Chrome friendly error page -->


result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
SharedWorker
The SharedWorker API allows scripts from multiple tabs to share a background thread of computation. If SharedWorker is not partitioned, then it can be abused to shared data between websites in your browser.
              
Passed
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: 
Error: no SharedWorker message received,
Error: no SharedWorker message received,
Error: no SharedWorker message received

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Passed
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Passed
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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 {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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 (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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 {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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 (secret) => {
      try {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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 {
        let worker = new SharedWorker("supercookies_sharedworker.js");
        worker.port.start();
//        console.log("worker", worker);
        const messagePromise = new Promise((resolve) => {
          worker.port.onmessage = (e) => resolve(e.data);
        });
        worker.port.postMessage(secret);
        await messagePromise;
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let worker = new SharedWorker("supercookies_sharedworker.js");
      worker.port.start();
      const messagePromise = new Promise((resolve, reject) => {
        worker.port.onmessage = (e) => resolve(e.data);
        setTimeout(() => reject(new Error("no SharedWorker message received")), 200);
      });
      worker.port.postMessage("request");
      const message = await messagePromise;
      if (message === "none") {
        throw new Error("Unsupported");
      }
      return message;
    }

result, same first party: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
TLS Session ID
The TLS protocol is used by HTTPS to make connections secure. If the browser were to re-use a TLS session, then the session ID could be used to track users across websites.
              
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

result, same first party: 
9603dd9e70506749fc7ada3e2f04667d98c75c6b0c4279d9fc0e6c48362585bd,
d83e6ae6ccc926f1409abdfddfc30a12b9b75a606d7d0d560d2596932f2fb351,
c5ce6bbea73e8c2b4c72d194462c7fa7a5f024f2716e5b3ab616ff4ae968be54

result, different first party: 
2cf53647f458850c9ec9cf625f0b2c38126e45466142abfa7ae0911fd0243182,
6a505680936b3a5a06ede2b6e42d741ca262b72541187e34aa9957b632808253,
e4df2cfc360ef08bb171d3064de313bd1c7df1d968fe3c128c328fcefba4def0

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: 
2e04bde8ec5d05a0209644749aa9983fecf4ae1c9017f86dfdbddad3deeb3856,
94a7b8502f9f4e906855b0cc80686a9a909acdb5fb4a798403dac3524ba54fd5,
a0de92e94824bf2be2ab3f046e80e0f337a081af4ea81424dd7c68d64bd31c6a,
13f0e803f6fd4dc6339f76ecf043ee7f793ec29d8f957940f4d499559ba57776

result, different first party: 
678045155dbed5020d45c30f422837a0f78fdfe612fab80f2fcd28f2ad59e576,
5703bfe619e74c2962e6ed1a6ae8c4a4f5c930524a43092e461ae9d7bbb5788b,
83b9609426d97825d564ee1c76d6422ac30a7bab5bc66d200895d0b032e25aec,
c3b33d909a6008ddc051a199bac655f4cf205521206cc0eeace8c62d860cc6c7

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

result, same first party: 
ba095a254203bf30dfd4fd5d89e820e54f633c968ef1775595d15e0532e73fa2,
ca14c0830272ac26a85972df2a21c070d976be950e4f0c13c5d95b77bdbea136,
dda4ccc5a461fdcac3360fba49ef27d071de99570288f8cc1cd6c17386ac170e

result, different first party: 
93279165069e8839d24185231fb09e360513a70a3e06923bc242c21abb1b3d14,
9175b71726ce90c099cd3c2547af640f3a4d800ca431c7aecd4f4d3dca835fb7,
35d46e4895d56dcdcf0d24e645df79976ad8376fc73b603cdf92f58264550854

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: 
636a29ab9d6c4af720ebbd75cff3826a45a2faad0c55e65b1e256fc9140b9772,
ec844a90018ce91f2b926dc406f9c9afb19ebcf680de8441c48c4fe66fb2b4d7,
7f7a02ef15b332c2a5f6f667e646c6a1e6e450842ecb05875b4d6c322594d74a,
9257e7a8c9614e53fd057411366dc4332115b66d1724f8725a2e671a63c20d23,
6da406751ec347965c091821c5624d643e3f29f51bc57ad7ca9d443fe891c73b

result, different first party: 
d31b77f5cdbabbbc23b086961cbcdb3b68d068ea392751b54ccab71d66bd3c91,
d931ea8c66ac0131ec77391b890283fdd9c60b05a7e6c3cf1a06db78c4a99b95,
74ff4b617bdba5b6f309eeed0aae9ec61af1715ae3db1051f053717548c1e97f,
f24f2f5ec15fa98a98dd17259ee1580a21c924aaa8374748f22211bc17ebc40b,
0a8b212a967ffa918f373ea4d6a09d73521951668f5886f4bcf50cd6c5b0da2e

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: 
e625fe6a92291ab186b9404e308215479544783ec169c3da148ec03be55ce7e3,
1afac92a043711e8bb439be8a7241a835637781f2874e698cb90f21be9b12cd4,
2c72176bea0df3789acc65d11e3dcceb11ccfe0ad7e09fff6eb9879324620bfa,
431ed868e13ac1c467a209e99e7c23bf46d0ac6b36fa21d170891e324b7662f0

result, different first party: 
65cea8191019f2ff89f59edba930161d6cc4b48ee2361c1f64e8e050f6882990,
5e9f8c31c863cfede08d374ded21ad1a0e50e39c8fa5c4ae0aca418860f492d5,
542b304a599520f7ad1d2dae91c2089ad58eb9d01c1875b351697d07da4015be,
312364f3a70a5e51303dc9929778c672c1b23065e01787fc40c6b3607c85cab3

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

result, same first party: 
9b9cbe7b895ddf96a6798d0109799af5acb5ce5c01dd37ed5427bc3bb190ccdf,
38847a9a9d866b3817edfc41ec3f328e841f3b7c807e61f1832efbbb51b70787,
d11af7d089f0d8b9cb42cab43fa7ac6d3eab0592cf079cb77b9d40ca5039073f,
485fa2eec2caced5f2ecac483c5987fd2293bb01584d96e0b048fd423e060fda,
7e32fa4f6d0952106e758e28de25e32d972cacae6f5515c0c681c1b9f807c805

result, different first party: 
3d7c4e8012c0323a21721cb2d076287b575fdd5238bd5f8183982f7cbf970222,
5b82bd350ec286d664b101f4f2c943175003dad70b21888a3fe37faf3ee2922f,
947b6fa720f1b519a75a2a23f2839fcdc77d675430b3ba297a966a3c85d64d90,
8d1b1744bda1067b370b340105c33a8c6bde1046d8dd3d2cc36e461332b2ba95,
735b3592d72cbe0c0ab62bbe1b9448bf6c5e3a11d5afdb05dcaadc0d93758dcf

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: 
00ee983540f5aa80ae6a99edcf9b3375db4f03819db9e9b14f4b33f1b6216ba8,
dcd4edbcbb60e9be2a3af5c7ee41dacab051afd8f38430ebfb964017750dba25,
07f5e2cacb10c71b982ce44fcfc238584825f55f22549131322de377e2f6fff7,
9b1c06889f37e1db8851b5355cf8ee472a40283019b13ffa948fcde11e0935d7

result, different first party: 
5c21c34ceb450027edcd856a12cf31899572d4175678a49f25a49a58c2aa22c6,
9e83f45df79c0e4378a2f4ca17314cd0122fc5930d682f72348358ac580fdcb7,
6c04fe42be213fb1bfd6400d344da63790587806000619c84fcdc82730092449,
6b5b00c45408253ebaa18aa46a0bdabc1c7ae0b6d108dd93cc1e8396de84a75c

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

read: async () => {
      let results = await fetch("https://tls.privacytests2.org:8900/");
      return (await results.json()).sessionId;
    }

result, same first party: 
97d7e1a0ca8681b45cf19c643a8e37507f8adcccc3669775c8785e0319acd1d5,
e0cbe5e4645c438d6a6952b38979c9d28ed16407f394ce2f2e67699f488a2d2c,
af5fd0062061c15b18db17df045805226c507b0ef570d7e88c905669bd1117c4,
d3508543e761335400db40de29ca203b874f3a292c667011f6c955a4682bbe0c,
21d3604616aad2d9cd0cb132e068b8f135c304c81517e5bed9fe514385728325

result, different first party: 
815f0bd0406225e79e4d7a3825ea1551b131d08c29948ceb67c6e5ed3607fbd5,
c22565c9787def613347153e0f2a2304eca970672209cdd61aecec3f04f1de56,
3b0c0a44d505b9b3ea5170e2c7b7282b191bc560cd546b404a6c7dc35b9cf9da,
518ab355e5d32c5249d9446993c04143f8598a76fcec88c9e20a6bf7115a5696,
2ead00e31b6119639709d6342f15782ec9ff248967a98cd651a73d62fc53dafe

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: 
137b22146051236970aabffc4fd27b8228770439b480d197ce6268d2b5c10fd4,
1a69304e3e1bef5cc39c9b9e8227780165884145bb62d1695d06755ac55889ef,
5748ee621047e1f8743f152849f46aa5ed5a1701766b4e8d7c64b0f2052be9c3,
3c5abfbf483000cde4d4136f0e2849172a240b10d1feda2e2d725de428c8c0ab,
5545d901f4f6d446988accbf15177eb76cbec3c86a6a43c8a805159228e33721

result, different first party: 
3e5e1d630dd3a84c4f5aec117b26ad458b167d633f97c5b8be0dfbc1731f42ed,
10f4a1c90aeca05b277a8f202aa9ede70b7cb6cc0078dcc262ccbb4908ef7734,
18e9fe215dc7ffb4045ab356829b61ddf13c96f838e5fbf8619f1310c41934b8,
18041f179f329f23840f4ec611a0da86ddb0a1bef8db35eabd54c60ca6b9fe00,
576df6d96951f55de38d189435495ca8fb90415a274e9ac55d8cde4341a6348c

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: 
79ef769c4b9f86f1675b2efd39d45986f91bb76c7d533d7386590e7d022e04df,
d25bfc08b0c9bf4e30f36165f53b7b1b947e51b1cc67d25151e23ffd420bbb9f,
e5fa7f5b2562ef95469730b93f556d216a1a0bc2d12c02f20bf331aaed13a512,
b7f5b3b2c97c9088f209267e6fcdc87924fef960794a947650abced44e1b6893,
5e32bfcf80cc413f2f4d9183584bba21f4d5d1c2ef4113b29c625d56ddcbe6cf

result, different first party: 
a782b3324a3a16105e0ec88650ba1dcd8dc06fd39b90d377584a857cbd9bd32d,
968872dec3f244d7b4582a5aa2405b6a79e8947dd8d01d9c967e24dd171b26ed,
4f42693bf607096ae2e81379cbc4317512a12710c3b45eec33641fcd4ef59905,
fb044cd9832771524a3183380951a754d2ee6ccb8be2137d0131cfc7b7ff2bde,
cde69350d4804d791930d415b64f275fecc6c009f7c25c51703c4231379a4e5c

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: 
a56dc3f2d8c36d16f18185e2f0190a057b7a16fa750b25b6d10240da7ada047b,
3effe617311dae4b098eb056536f0f853dfb0d796fda468b1094e168ee8edb6b,
88738fb74ffed4802c5709d632e7a1c82a853be35deb84aa5ed95a38eb02e1ec,
d1d331403141d75c07f435461f1028af9321499e3f52976bbad02b72ad90142e

result, different first party: 
a438eb7b6c227b82f1da06157ae778a3b2ba9dc3960b7531f95d634852ed9a29,
f12d08bba10543e126b95daab1cc10a3c74014ce373b28260a6eb370658334aa,
2ca5aac3fdc58303eb842db102dc5dbf9a60c02f43bee5acc53ce249493482e2,
bf24d290f714d2a464bfb29608a936eca1c63bf7ef97aaccb8d36bc6dc5615b0

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Web SQL Database
The Web SQL Database is a deprecated web API for storing data in an SQL database.
              
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false

passed: undefined

test failed: true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false

passed: undefined

test failed: true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false

passed: undefined

test failed: true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false

passed: undefined

test failed: true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false

passed: undefined

test failed: true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: Web SQL is deprecated,
Error: Web SQL is deprecated,
Error: Web SQL is deprecated,
Error: Web SQL is deprecated,
Error: Web SQL is deprecated

result, different first party: 
Error: Web SQL is deprecated,
Error: Web SQL is deprecated,
Error: Web SQL is deprecated,
Error: Web SQL is deprecated,
Error: Web SQL is deprecated

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false, false

passed: undefined

test failed: true, true, true, true, true
Passed
write: async (key) => {
      if (!window.openDatabase) {
        throw new Error("gported");
      }
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let tx = new Promise((resolve) => database.transaction(tx => {
        tx.executeSql(
          `CREATE TABLE IF NOT EXISTS cache(
             id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
             name TEXT NOT NULL,
             value TEXT NOT NULL,
             UNIQUE (name)
           )`,
          [], (tx, rs) => {}, (tx, err) => {});
        tx.executeSql(
          `INSERT OR REPLACE INTO cache(name, value)
           VALUES(?, ?)`,
          ["secret", key], (tx, rs) => {}, (tx, rs) => {});
      }));
    }

read: async () => {
      let database = window.openDatabase("sqlite_supercookie", "", "supercookie", 1024 * 1024);
      let result = await new Promise((resolve, reject) => database.transaction(tx => {
        tx.executeSql(
          "SELECT value FROM cache WHERE name=?",
          ["secret"],
          (tx, rs) => resolve(rs),
          (tx, err) => reject(err));
      }));
      return result.rows.item(0).value;
    }

result, same first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

result, different first party: 
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function,
Error: window.openDatabase is not a function

unsupported: false, false, false, false

passed: undefined

test failed: true, true, true, true
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

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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }

read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1

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, 2

result, different first party: 2, 2, 2, 2, 3

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }

read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1, 1

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }

read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }

read: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      let countResponse = await fetch(testURI("ctr", "xhr", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same first party: 1, 1, 1, 1, 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

result, different first party: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Navigation testsWhich browsers prevent websites from sharing tracking data when you click on a link?
When you click a hyperlink to navigate your browser from one site to another, certain browser APIs allow the first site to communicate to the second site. These privacy vulnerabilities can be fixed by introducing new limits on how much data is transfered between sites.',
        
document.referrer
The Referer [sic] request header is a mechanism used by browsers to let a website know where the user is visiting from. This header is inherently tracking users across websites. In recent times, browsers have switched to a policy of trimming a referrer to convey less tracking information, but Referer continues to convey cross-site tracking data by default.
              
Failed
write: (secret) => { /* do nothing */ }

read: () => document.referrer

result, same first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/

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/

result, different first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => { /* do nothing */ }

read: () => document.referrer

result, same first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/

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/

result, different first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => { /* do nothing */ }

read: () => document.referrer

result, same first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
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/

result, different first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => { /* do nothing */ }

read: () => document.referrer

result, same first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
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/

result, different first party: 
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
sessionStorage
The sessionStorage API is similar to the localStorage API, but it does not persist across tabs or across browser sessions. Nonetheless, it can be used to track users if they navigate from one website to another. This tracking can be thwarted by partitioning sessionStorage between websites.
              
Passed
write: (secret) => sessionStorage.setItem("secret", secret)

read: () => sessionStorage.getItem("secret")

result, same first party: 
3fce2098-7e9d-4ba9-b078-272e478188d5,
96e35e8b-83e3-40bb-90b2-81254058442a,
42faff19-a4d5-4440-8137-9f83240f2c24

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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f,
8d0209a9-77a1-45f6-a4b5-a9584894699d,
1d5f5063-ff3c-4279-be0f-6dfede562600,
376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)

read: () => sessionStorage.getItem("secret")

result, same first party: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008,
d1f11452-ef14-4b18-9359-f76b7ebf1e79,
b5df093b-83a0-4796-9013-592159fae4bb

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: 
95329b24-dd1c-4e1a-aceb-23514fa75612,
960952de-fbd6-4278-85f0-c562117c1b2c,
513eaf28-ece4-412a-8b4f-4c6ec782bee8,
3d908420-2f5e-44f6-a751-14480e05325b,
74f635c4-6e5d-46d5-86e6-7c65b75369f1

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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
c7a7c812-94af-406a-b0f4-a3e96ac970f5,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)

read: () => sessionStorage.getItem("secret")

result, same first party: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
670402ab-7c8e-498e-a2fc-412775b7bcd8,
bdd23153-2777-4dfe-839b-53c83748e0a7,
541a2489-bb99-46aa-a401-167bf5f8f9e3,
1c747676-e705-48b0-b808-613ddbd9f42e

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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
ab0df867-a081-4ab7-9441-fdccaa9a7aab,
337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => sessionStorage.setItem("secret", secret)

read: () => sessionStorage.getItem("secret")

result, same first party: 
e76bfdd1-0491-4b90-b570-3868442520c4,
1eca2786-e863-40a4-aa45-8b3d77537dd3,
bca01b74-5bc7-4b7a-9e37-c83bb8833959,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
5bac69f9-2e81-4d64-8833-116de9ad280b,
9b9b853c-fb5e-4113-9bc7-5324994c3313,
61bcf04a-8b1c-4354-b756-c6aded26aa47,
6958e9c5-1694-469a-88ea-e72d4b5bb2af

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: 
4c38ebec-4414-4b26-9494-20bc35ae55be,
c9631ac6-c811-4462-b6b6-7df4aa91b25b,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
b3a4e711-f75e-4c0b-be54-f0882233165b,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

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: 
f2f031ec-3fda-40df-bf47-ba901a076318,
68136c5b-37e8-4e21-ae51-67439b43e4c0,
1b14187b-5343-4343-9cbe-a884e4b82b0a,
76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
window.name
The window.name API allows websites to store data that will persist after the user has navigated the tab to a different website. This mechanism could be partitioned so that data is not allowed to persist between websites.
              
Passed
write: (secret) => window.name = "name_" + secret

read: () => window.name

result, same first party: 
name_3fce2098-7e9d-4ba9-b078-272e478188d5,
name_96e35e8b-83e3-40bb-90b2-81254058442a,
name_42faff19-a4d5-4440-8137-9f83240f2c24

result, different first party: , , 

unsupported: false, false, false

passed: true, true, true

test failed: false, false, false
Failed
write: (secret) => window.name = "name_" + secret

read: () => window.name

result, same first party: 
name_615467f4-5b59-4ebb-a5f7-eced31718e7f,
name_8d0209a9-77a1-45f6-a4b5-a9584894699d,
name_1d5f5063-ff3c-4279-be0f-6dfede562600,
name_376bcea2-2ac1-40b3-918e-4e8e864e1535

result, different first party: 
name_615467f4-5b59-4ebb-a5f7-eced31718e7f,
name_8d0209a9-77a1-45f6-a4b5-a9584894699d,
name_1d5f5063-ff3c-4279-be0f-6dfede562600,
name_376bcea2-2ac1-40b3-918e-4e8e864e1535

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret

read: () => window.name

result, same first party: 
name_006e8a38-27a7-4344-8f7d-a5eb4d93f008,
name_d1f11452-ef14-4b18-9359-f76b7ebf1e79,
name_b5df093b-83a0-4796-9013-592159fae4bb

result, different first party: 
name_006e8a38-27a7-4344-8f7d-a5eb4d93f008,
name_d1f11452-ef14-4b18-9359-f76b7ebf1e79,
name_b5df093b-83a0-4796-9013-592159fae4bb

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_95329b24-dd1c-4e1a-aceb-23514fa75612,
name_960952de-fbd6-4278-85f0-c562117c1b2c,
name_513eaf28-ece4-412a-8b4f-4c6ec782bee8,
name_3d908420-2f5e-44f6-a751-14480e05325b,
name_74f635c4-6e5d-46d5-86e6-7c65b75369f1

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_b3e158a6-9ff3-4bc0-aff8-a970bc973d16,
name_c7a7c812-94af-406a-b0f4-a3e96ac970f5,
name_76f05b0a-7992-4450-ac2c-381b0cd8a0cd,
name_266fad2e-6322-4934-8fa0-1414fb15087c

result, different first party: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret

read: () => window.name

result, same first party: 
name_a0266c8c-ac70-40f9-b11c-d8dfbecdee51,
name_670402ab-7c8e-498e-a2fc-412775b7bcd8,
name_bdd23153-2777-4dfe-839b-53c83748e0a7,
name_541a2489-bb99-46aa-a401-167bf5f8f9e3,
name_1c747676-e705-48b0-b808-613ddbd9f42e

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_55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
name_7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
name_ab0df867-a081-4ab7-9441-fdccaa9a7aab,
name_337c4058-1e91-4e08-980e-c55996dae7a5

result, different first party: 
name_55369d9a-dab8-4cc6-98eb-7c9d26ab67e3,
name_7316f7c1-21e6-4136-b8c1-6c1265ad71ef,
name_ab0df867-a081-4ab7-9441-fdccaa9a7aab,
name_337c4058-1e91-4e08-980e-c55996dae7a5

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: (secret) => window.name = "name_" + secret

read: () => window.name

result, same first party: 
name_e76bfdd1-0491-4b90-b570-3868442520c4,
name_1eca2786-e863-40a4-aa45-8b3d77537dd3,
name_bca01b74-5bc7-4b7a-9e37-c83bb8833959,
name_8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5,
name_2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3

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_5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020,
name_5bac69f9-2e81-4d64-8833-116de9ad280b,
name_9b9b853c-fb5e-4113-9bc7-5324994c3313,
name_61bcf04a-8b1c-4354-b756-c6aded26aa47,
name_6958e9c5-1694-469a-88ea-e72d4b5bb2af

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_4c38ebec-4414-4b26-9494-20bc35ae55be,
name_c9631ac6-c811-4462-b6b6-7df4aa91b25b,
name_d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
name_b3a4e711-f75e-4c0b-be54-f0882233165b,
name_cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

result, different first party: 
name_4c38ebec-4414-4b26-9494-20bc35ae55be,
name_c9631ac6-c811-4462-b6b6-7df4aa91b25b,
name_d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2,
name_b3a4e711-f75e-4c0b-be54-f0882233165b,
name_cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: (secret) => window.name = "name_" + secret

read: () => window.name

result, same first party: 
name_f2f031ec-3fda-40df-bf47-ba901a076318,
name_68136c5b-37e8-4e21-ae51-67439b43e4c0,
name_1b14187b-5343-4343-9cbe-a884e4b82b0a,
name_76037bad-07bc-410e-a311-7fbf2b5787a5

result, different first party: 
name_f2f031ec-3fda-40df-bf47-ba901a076318,
name_68136c5b-37e8-4e21-ae51-67439b43e4c0,
name_1b14187b-5343-4343-9cbe-a884e4b82b0a,
name_76037bad-07bc-410e-a311-7fbf2b5787a5

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
HTTPS testsWhich browsers prevent unencrypted network connections?
HTTPS is the protocol that web browsers use to connect securely to websites. When HTTPS is being used, the connection is encrypted so that third parties on the network cannot read content being sent between the server and your browser. In the past, insecure connections were the default and websites would need to actively request that a browser use HTTPS. Now the status quo is shifting, and browser makers are moving toward a world where HTTPS is the default protocol.`
        
Insecure website warning
Checks to see if the browser stops loading an insecure website and warns the user before giving them the option to continue. Known as HTTPS-Only Mode in some browsers.
              
Failed
passed: false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Passed
passed: true, true, true, true
result: 
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
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
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
Failed
passed: false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Upgradable address
Checks to see if an insecure address entered into the browser's address bar is upgraded to HTTPS whenever possible.
              
Passed
upgraded: true, true, true
passed: true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true
passed: true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
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
passed: true, true, true, true
Upgradable hyperlink
Checks to see if the user has clicked on a hyperlink to an insecure address, if the browser upgrades that address to HTTPS whenever possible.
              
Passed
upgraded: true, true, true
passed: true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true
passed: true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
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
passed: true, true, true, true
Upgradable image
Checks to see if the browser attempts to upgrade an insecure address for an image to HTTPS whenever possible.
              
Passed
passed: true, true, true
result: upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true
result: upgraded, upgraded, upgraded
Failed
passed: false, false, true, false, false
result: 
loaded insecurely,
loaded insecurely,
upgraded,
loaded insecurely,
loaded insecurely
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Failed
passed: false, false, false, false, false
result: 
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Upgradable script
Checks to see if the browser attempts to upgrade an insecure address for an script to HTTPS whenever possible.
              
Passed
passed: true, true, true
result: blocked, blocked, blocked
Passed
passed: true, true, true, true
result: 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
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: 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
Passed
passed: true, true, true, true
result: blocked, blocked, blocked, blocked
Misc testsWhich browsers provide additional assorted privacy protections?
This category includes tests for the presence of miscellaneous privacy features
        
ECH enabled
Encrypted Client Hello (ECH) is a new protocol that hides the website you are visiting from third-party network eavesdroppers.
              
Passed
SNI_status: encrypted
passed: true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true
Passed
SNI_status: encrypted
passed: true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: encrypted
passed: true, true, true, true, false
Passed
SNI_status: encrypted
passed: true, true, true, true
GPC enabled first-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a website not to sell the user's personal data to third parties. This test checks to see if the GPC header is sent by default to the top-level website.
              
Passed
header value: 1
passed: true, true, true
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false
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
Failed
passed: false, false, false, false
Failed
passed: false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
IP address leak
IP addresses can be used to uniquely identify a large percentage of users. A proxy, VPN, or Tor can mask a user's IP address.
              
Failed
passed: false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
Stream isolation
Browsers that use Tor can use a different Tor circuit per top-level website.
              
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true
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
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true
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
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, 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
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, 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: 
2001:67c:6ec:203:192:42:116:188,
2001:67c:6ec:203:192:42:116:197,
178.218.144.51,
2a02:16d0:0:5::1,
2602:fc24:18:1c54::1
readDifferentFirstParty: 
23.154.177.7,
2001:67c:6ec:203:192:42:116:219,
212.95.50.77,
89.58.18.10,
2001:67c:6ec:203:192:42:116:175
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
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Tor enabled
The Tor network sends the browser's web requests through a series of relays to hide a user's IP address, thereby helping to mask their identity and location. This test checks to see if the Tor network is being used by default.
              
Failed
IsTorExit: false, false, false
passed: false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false
passed: false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Passed
IsTorExit: true, true, true, true, true
passed: true, true, true, true, true
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Fingerprinting resistance testsWhich browsers hide what's unique about your device?
Fingerprinting is a technique trackers use to uniquely identify you as you browse the web. A fingerprinting script will measure several characteristics of your browser and, combining this data, will build a fingerprint that may uniquely identify you among web users. Browsers can introduce countermeasures, such as minimizing the distinguishing information disclosed by certain web APIs so your browser is harder to pick out from the crowd (so-called 'fingerprinting resistance').`,
        
Media query screen height
Height of the user's screen in pixels.
              
Passed
expression: undefined
desired expression: undefined
actual value: 1299,1298,1300
desired value: undefined
passed: true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440
desired value: undefined
passed: false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: 900,900,900,900
desired value: undefined
passed: true,true,true,true
Passed
expression: undefined
desired expression: undefined
actual value: 900,900,900,900,900
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: 900,900,900,900,900
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Media query screen width
Width of the user's screen in pixels.
              
Passed
expression: undefined
desired expression: undefined
actual value: 1208,1207,1207
desired value: undefined
passed: true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560
desired value: undefined
passed: false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: 1600,1600,1600,1600
desired value: undefined
passed: true,true,true,true
Passed
expression: undefined
desired expression: undefined
actual value: 1400,1400,1400,1400,1400
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false,false
Passed
expression: undefined
desired expression: undefined
actual value: 1400,1400,1400,1400,1400
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
outerHeight
Height of the browser window in pixels, including browser chrome.
              
Passed
expression: outerHeight
desired expression: undefined
actual value: 1299,1298,1300
desired value: undefined
passed: true,true,true
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,1371,1371,1371
desired value: undefined
passed: false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,1371,1371
desired value: undefined
passed: false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1040,1040,1040,1040,1040
desired value: undefined
passed: false,false,false,false,false
Passed
expression: outerHeight
desired expression: undefined
actual value: 900,900,900,900
desired value: undefined
passed: true,true,true,true
Passed
expression: outerHeight
desired expression: undefined
actual value: 900,900,900,900,900
desired value: undefined
passed: true,true,true,true,true
Failed
expression: outerHeight
desired expression: undefined
actual value: 1061,0,1061,1061
desired value: undefined
passed: false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1335,1335,1335,1335,1335
desired value: undefined
passed: false,false,false,false,false
Passed
expression: outerHeight
desired expression: undefined
actual value: 900,900,900,900,900
desired value: undefined
passed: true,true,true,true,true
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,1371,1371,1371,1371
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1371,1371,1371,1371
desired value: undefined
passed: false,false,false,false
screen.height
Height of the user's screen, in pixels.
              
Passed
expression: screen.height
desired expression: undefined
actual value: 1299,1298,1300
desired value: undefined
passed: true,true,true
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440
desired value: undefined
passed: false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screen.height
desired expression: undefined
actual value: 900,900,900,900
desired value: undefined
passed: true,true,true,true
Passed
expression: screen.height
desired expression: undefined
actual value: 900,900,900,900,900
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screen.height
desired expression: undefined
actual value: 900,900,900,900,900
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.height
desired expression: undefined
actual value: 1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false
screen.width
Width of the user's screen, in pixels.
              
Passed
expression: screen.width
desired expression: undefined
actual value: 1208,1207,1207
desired value: undefined
passed: true,true,true
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560
desired value: undefined
passed: false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screen.width
desired expression: undefined
actual value: 1600,1600,1600,1600
desired value: undefined
passed: true,true,true,true
Passed
expression: screen.width
desired expression: undefined
actual value: 1400,1400,1400,1400,1400
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screen.width
desired expression: undefined
actual value: 1400,1400,1400,1400,1400
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screen.width
desired expression: undefined
actual value: 2560,2560,2560,2560
desired value: undefined
passed: false,false,false,false
screenX
Position, in pixels, of the left edge of the browser window on screen.
              
Passed
expression: screenX
desired expression: undefined
actual value: 2,6,8
desired value: undefined
passed: true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 22,22,22,22
desired value: undefined
passed: false,false,false,false
Failed
expression: screenX
desired expression: undefined
actual value: 22,22,22
desired value: undefined
passed: false,false,false
Passed
expression: screenX
desired expression: undefined
actual value: 4,4,4,4,4
desired value: undefined
passed: true,true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0
desired value: undefined
passed: true,true,true,true
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 320,0,320,320
desired value: undefined
passed: false,true,false,false
Failed
expression: screenX
desired expression: undefined
actual value: 1329,1329,1329,1329,1329
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screenX
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 22,22,22,22,22
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screenX
desired expression: undefined
actual value: 22,22,22,22
desired value: undefined
passed: false,false,false,false
screenY
Position, in pixels, of the top edge of the browser window on screen.
              
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,8
desired value: undefined
passed: true,true,true
Failed
expression: screenY
desired expression: undefined
actual value: 47,47,47,47
desired value: undefined
passed: false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 47,47,47
desired value: undefined
passed: false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 25,25,25,25,25
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0
desired value: undefined
passed: true,true,true,true
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screenY
desired expression: undefined
actual value: 202,0,202,202
desired value: undefined
passed: false,true,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 25,25,25,25,25
desired value: undefined
passed: false,false,false,false,false
Passed
expression: screenY
desired expression: undefined
actual value: 0,0,0,0,0
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screenY
desired expression: undefined
actual value: 47,47,47,47,47
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 47,47,47,47
desired value: undefined
passed: false,false,false,false
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
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false
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
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
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
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
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
__hssc
HubSpot tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
__hstc
HubSpot tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
__s
Drip.com email address tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
_hsenc
HubSpot tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
_openstat
Yandex tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
dclid
DoubleClick Click ID (Google)
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
fbclid
Facebook Click Identifier
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
gclid
Google Click Identifier
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
hsCtaTracking
HubSpot tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
mc_eid
Mailchimp Email ID (email recipient's address)
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
mkt_tok
Adobe Marketo tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
ml_subscriber
MailerLite email tracking
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
ml_subscriber_hash
MailerLite email tracking
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
msclkid
Microsoft Click ID
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
oly_anon_id
Omeda marketing 'anonymous' customer id
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
oly_enc_id
Omeda marketing 'known' customer id
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
rb_clickid
Unknown high-entropy tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
s_cid
Adobe Site Catalyst tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
vero_conv
Vero tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
vero_id
Vero tracking parameter
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
wickedid
Wicked Reports e-commerce tracking
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
yclid
Yandex Click ID
              
Passed
passed: true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 8303910894658098
passed: false, false, false, false, false
Failed
value: 8303910894658098
passed: false, false, false, false
Tracker content blocking testsWhich browsers block important known tracking scripts and pixels?
When you visit a web page, it frequently has third-party embedded tracking content, such as scripts and tracking pixels. These embedded components spy on you. Some browsers and browser extensions maintain list of tracking companies and block their content from being loaded. This section checks to see if a browser blocks 20 of the largest trackers listed by https://whotracks.me.`
        
Adobe
Tests whether the browser blocks the page from loading the tracker at https://munchkin.marketo.net/munchkin.js
              
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false
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
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true
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
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
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
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true
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
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false
AppNexus
Tests whether the browser blocks the page from loading the tracker at https://ib.adnxs.com/px?id=178248&t=1
              
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true
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
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true
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, 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
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false
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
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true
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
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false
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
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
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
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false
Facebook tracking
Tests whether the browser blocks the page from loading the tracker at https://connect.facebook.net/en_US/fbevents.js
              
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true
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
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
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, 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
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false
Google Analytics
Tests whether the browser blocks the page from loading the tracker at https://google-analytics.com/urchin.js
              
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false
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
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false
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
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
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
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
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false
New Relic
Tests whether the browser blocks the page from loading the tracker at https://js-agent.newrelic.com/nr-1212.min.js
              
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false
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
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
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false
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
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
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
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false
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
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false
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
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
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
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
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true
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
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false
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
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true
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
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
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false
Tracking cookie protection testsWhich browsers block important known tracking cookies?
A large fraction of web pages on the web have hidden third-party trackers that read and write cookies in your browser. These cookies can be used to track your browsing across websites. This section checks to see if a browser stops cross-site tracking by cookies from 20 of the largest trackers listed by https://whotracks.me.`,
        
Adobe
Tests whether the browser stops cookies from munchkin.marketo.net from tracking users across websites.
              
Passed
passed: true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, true, true, true
Adobe Audience Manager
Tests whether the browser stops cookies from dpm.demdex.net from tracking users across websites.
              
Passed
passed: true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: true, true, true, true
Amazon adsystem
Tests whether the browser stops cookies from s.amazon-adsystem.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, true, true, true
AppNexus
Tests whether the browser stops cookies from ib.adnxs.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true
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
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: 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
Failed
passed: false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true, true
Bing Ads
Tests whether the browser stops cookies from bat.bing.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true
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
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true
Chartbeat
Tests whether the browser stops cookies from static.chartbeat.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true
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
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: 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
Failed
passed: false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true, true
Criteo
Tests whether the browser stops cookies from dis.criteo.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: 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
Failed
passed: false, false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, true, true, true
DoubleClick (Google)
Tests whether the browser stops cookies from securepubads.g.doubleclick.net from tracking users across websites.
              
Passed
passed: true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: 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
Failed
passed: false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, true, true, true
Facebook tracking
Tests whether the browser stops cookies from connect.facebook.net from tracking users across websites.
              
Passed
passed: true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: 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
Failed
passed: false, false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, true, true, true
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
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://www.google.com/pagead/1p-user-list/
cookieFound: 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
Failed
passed: false, false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, true, true, true
Google Analytics
Tests whether the browser stops cookies from google-analytics.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true
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
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true
Google Tag Manager
Tests whether the browser stops cookies from www.googletagmanager.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true
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
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: 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
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Index Exchange
Tests whether the browser stops cookies from dsum-sec.casalemedia.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, true, true, true
New Relic
Tests whether the browser stops cookies from js-agent.newrelic.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true
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
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: 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
Failed
passed: false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true, true
Quantcast
Tests whether the browser stops cookies from pixel.quantserve.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, true, true, true
Scorecard Research Beacon
Tests whether the browser stops cookies from sb.scorecardresearch.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true
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
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: 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
Failed
passed: false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true, true
Taboola
Tests whether the browser stops cookies from trc.taboola.com from tracking users across websites.
              
Passed
passed: true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: 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
Failed
passed: false, false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, true, true, true
Twitter pixel
Tests whether the browser stops cookies from t.co from tracking users across websites.
              
Passed
passed: true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true
Failed
passed: false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true
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
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true
Yandex Ads
Tests whether the browser stops cookies from yandex.ru from tracking users across websites.
              
Passed
passed: true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false
Failed
passed: false, false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, true, true, true
Passed
passed: true, true, true
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
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: 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
Failed
passed: false, false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, 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
Failed
passed: false, false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, true, true, true
Cross-session first-party tracking testsWhich browsers prevent websites from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow websites ("first parties") to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
        
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
              
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3

result, different session: h3, h3, h3

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3, h3

result, different session: h3, h3, h3, h3

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3

result, different session: h3, h3, h3

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3, h3, h3

result, different session: h3, h3, h3, h3, h3

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

result, different session: h2, h2, h2, h2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same 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
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3, h3

result, different session: h3, h3, h3, h3

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h2, h2, h3, h2, h3

result, different session: h3, h3, h2, h3, h2

unsupported: true, true, false, true, false

passed: , true, true

test failed: false, false, false, false, false
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h2, h2, h2, h2, h2

result, different session: h2, h2, h2, h2, h2

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3, h3, h3

result, different session: h3, h3, h3, h3, h3

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

read: async () => {
      const protocol = await fetchText(altSvcOrigin + "/protocol");
      if ((new URL(location)).searchParams.get("thirdparty") === "same") {
        if (protocol !== "h3") {
          throw new Error("Unsupported");
        }
      }
      return protocol;
    }

result, same session: h3, h3, h3, h3

result, different session: h3, h3, h3, h3

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
CacheStorage
The Cache API is a content storage mechanism originally introduced to support ServiceWorkers. If the same Cache object is accessible to multiple websites, it can be abused to track users.
              
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

result, different session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

result, different session: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

result, different session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p,
960952de-fbd6-4278-85f0-c562117c1b2c_1p,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p,
3d908420-2f5e-44f6-a751-14480e05325b_1p,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_1p

result, different session: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p,
960952de-fbd6-4278-85f0-c562117c1b2c_1p,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p,
3d908420-2f5e-44f6-a751-14480e05325b_1p,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16_1p,
c7a7c812-94af-406a-b0f4-a3e96ac970f5_1p,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd_1p,
266fad2e-6322-4934-8fa0-1414fb15087c_1p

result, different session: 
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined,
Error: cacheKeys[0] is undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
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
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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

result, different session: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same session: 
e76bfdd1-0491-4b90-b570-3868442520c4_1p,
1eca2786-e863-40a4-aa45-8b3d77537dd3_1p,
bca01b74-5bc7-4b7a-9e37-c83bb8833959_1p,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5_1p,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3_1p

result, different session: 
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same session: 
Error: 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
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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

result, different session: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: async (key) => {
      try {
        let cache = await caches.open("supercookies");
        cache.addAll([`test.css?key=${key}`]);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: async () => {
      let cache = await caches.open("supercookies");
      let cacheKeys = await cache.keys();
      let url = cacheKeys[0].url;
      return (new URL(url)).searchParams.get("key");
    }

result, same session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

result, different session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
              
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
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , , 

result, different session: , , , 

unsupported: true, true, true, true

passed: undefined

test failed: false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , 

result, different session: , , 

unsupported: true, true, true

passed: undefined

test failed: 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

passed: undefined

test failed: false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, 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

passed: undefined

test failed: false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
      await fetch(`${baseURI}cookie?secret=${secret}_http`);
    }

read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
      let response = await fetch(`${baseURI}headers`);
      let cookie = (await response.json())["cookie"];
      return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null;
    }

result, same session: , , , 

result, different session: , , , 

unsupported: true, true, true, true

passed: undefined

test failed: false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
              
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p_js,
96e35e8b-83e3-40bb-90b2-81254058442a_1p_js,
42faff19-a4d5-4440-8137-9f83240f2c24_1p_js

result, different session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p_js,
96e35e8b-83e3-40bb-90b2-81254058442a_1p_js,
42faff19-a4d5-4440-8137-9f83240f2c24_1p_js

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p_js,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p_js,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p_js,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p_js

result, different session: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p_js,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p_js,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p_js,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p_js

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p_js,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p_js,
b5df093b-83a0-4796-9013-592159fae4bb_1p_js

result, different session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p_js,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p_js,
b5df093b-83a0-4796-9013-592159fae4bb_1p_js

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p_js,
960952de-fbd6-4278-85f0-c562117c1b2c_1p_js,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p_js,
3d908420-2f5e-44f6-a751-14480e05325b_1p_js,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_1p_js

result, different session: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p_js,
960952de-fbd6-4278-85f0-c562117c1b2c_1p_js,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p_js,
3d908420-2f5e-44f6-a751-14480e05325b_1p_js,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16_1p_js,
c7a7c812-94af-406a-b0f4-a3e96ac970f5_1p_js,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd_1p_js,
266fad2e-6322-4934-8fa0-1414fb15087c_1p_js

result, different session: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same session: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51_1p_js,
670402ab-7c8e-498e-a2fc-412775b7bcd8_1p_js,
bdd23153-2777-4dfe-839b-53c83748e0a7_1p_js,
541a2489-bb99-46aa-a401-167bf5f8f9e3_1p_js,
1c747676-e705-48b0-b808-613ddbd9f42e_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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p_js,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p_js,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p_js,
337c4058-1e91-4e08-980e-c55996dae7a5_1p_js

result, different session: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p_js,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p_js,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p_js,
337c4058-1e91-4e08-980e-c55996dae7a5_1p_js

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same session: 
e76bfdd1-0491-4b90-b570-3868442520c4_1p_js,
1eca2786-e863-40a4-aa45-8b3d77537dd3_1p_js,
bca01b74-5bc7-4b7a-9e37-c83bb8833959_1p_js,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5_1p_js,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3_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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020_1p_js,
5bac69f9-2e81-4d64-8833-116de9ad280b_1p_js,
9b9b853c-fb5e-4113-9bc7-5324994c3313_1p_js,
61bcf04a-8b1c-4354-b756-c6aded26aa47_1p_js,
6958e9c5-1694-469a-88ea-e72d4b5bb2af_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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p_js,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p_js,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p_js,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p_js,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p_js

result, different session: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p_js,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p_js,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p_js,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p_js,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p_js

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: (secret) => {
      document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
    }

read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null

result, same session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p_js,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p_js,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p_js,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p_js

result, different session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p_js,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p_js,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p_js,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p_js

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers.
              
Failed
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

result, different session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

result, different session: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

result, different session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true

passed: undefined

test failed: false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

result, different session: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: (data) => {
      const msPerHour = 60 * 60 * 1000;
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      window.cookieStore.set({
        name: "partition_test",
        value: data,
        expires: Date.now() + msPerHour,
        sameSite: "none"
      });
    }

read: async () => {
      if (!window.cookieStore) {
        throw new Error("Unsupported");
      }
      const cookie = await window.cookieStore.get("partition_test");
      if (!cookie) {
        return null;
      }
      return cookie.value;
    }

result, same session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

result, different session: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

result, different session: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

result, different session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
              
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same session: 
fake_455341895044177,
fake_5332568459120868,
fake_6337063972903321

result, different session: 
fake_455341895044177,
fake_5332568459120868,
fake_6337063972903321

unsupported: false, false, false

passed: false, false, false

test failed: 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_11702401026735809,
fake_046629989186291576,
fake_5604669023240803,
fake_7248389143118841

result, different session: 
fake_11702401026735809,
fake_046629989186291576,
fake_5604669023240803,
fake_7248389143118841

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same session: 
fake_4012531682488587,
fake_7162349319853965,
fake_1143168061852653

result, different session: 
fake_4012531682488587,
fake_7162349319853965,
fake_1143168061852653

unsupported: false, false, false

passed: false, false, false

test failed: 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_45450351427750335,
fake_8885212392089368,
fake_7999934010973901,
fake_527775228399572,
fake_8365102483477826

result, different session: 
fake_45450351427750335,
fake_8885212392089368,
fake_7999934010973901,
fake_527775228399572,
fake_8365102483477826

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_9062988141625803,
fake_1336047196195873,
fake_5796303755138852,
fake_1429573224748666

result, different session: 
fake_588280546148537,
fake_2085154849178037,
fake_36913048965799944,
fake_06696846108676358

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same session: 
fake_244025568358881,
fake_7309694031908145,
fake_8659867348122741,
fake_5469873257300686,
fake_8754382366076816

result, different session: 
fake_40125276792107356,
fake_8637768289942263,
fake_434703006929128,
fake_36085746038029476,
fake_1354284032802564

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_23084030545517198,
fake_5658675992255491,
fake_27623454660167845,
fake_8534025572850517

result, different session: 
fake_23084030545517198,
fake_5658675992255491,
fake_27623454660167845,
fake_8534025572850517

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same session: 
fake_12460938007942701,
fake_47888122382488074,
fake_10205271292068385,
fake_6788711197997326,
fake_0429962008224265

result, different session: 
fake_12460938007942701,
fake_47888122382488074,
fake_10205271292068385,
fake_6788711197997326,
fake_0429962008224265

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_8066397853689726,
fake_3704503679674813,
fake_8322852256618702,
fake_33107260934661853,
fake_20705735988684637

result, different session: 
fake_6803644530182111,
fake_6284322806351239,
fake_4689958521093325,
fake_22347929451887705,
fake_6314974325345444

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_6046570787604122,
fake_11085073320277239,
fake_43163532528352966,
fake_44973592843145993,
fake_332035633156776

result, different session: 
fake_6046570787604122,
fake_11085073320277239,
fake_43163532528352966,
fake_44973592843145993,
fake_332035633156776

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return key;
    }

read: async (key) => {
      const href = testURI("resource", "css", key);
      const head = document.getElementsByTagName("head")[0];
      head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
      const testElement = document.querySelector("#css");
      let fontFamily;
      while (true) {
        await sleepMs(100);
        fontFamily = getComputedStyle(testElement).fontFamily;
        if (fontFamily.startsWith("fake")) {
          break;
        }
      }
      console.log(fontFamily);
      return fontFamily;
    }

result, same session: 
fake_6234861389202604,
fake_18805853043993426,
fake_951817137834414,
fake_045267691747792105

result, different session: 
fake_6234861389202604,
fake_18805853043993426,
fake_951817137834414,
fake_045267691747792105

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
favicon cache
A favicon is an icon that represents a website, typically shown in browser tab and bookmarks menu. If the favicon cache is not partitioned, it can be used to track users across websites.
              
Failed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: 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, 1

result, different session: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same 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

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same session: 1, 1, 1, 1, 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, 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
Failed
write: (key) => key

read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
      await sleepMs(2000);
      let response = await fetch(
        testURI("ctr", "favicon", key), {"cache": "reload"});
      let count = (await response.text()).trim();
      if (count === "0") {
        throw new Error("No requests received");
      }
      return count;
    }

result, same session: 2, 2, 2, 2

result, different session: 2, 2, 2, 2

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
fetch cache
When a resource is received via the Fetch API, it is frequently cached. That cache can potentially be abused for cross-site tracking.
              
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same 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

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      return key;
    }

read: async (key) => {
      let response = await fetch(testURI("resource", "fetch", key),
                                 {cache: "force-cache"});
      let countResponse = await fetch(testURI("ctr", "fetch", key),
                                      {cache: "reload"});
      return (await countResponse.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking.
              
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: 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: 2, 2, 2, 1, 1

result, different session: 2, 2, 2, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same 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

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

read: async (key) => {
      const text = document.createElement("span");
      text.id = "text";
      text.innerText = "test";
      document.body.appendChild(text);
      const originalWidth = text.getBoundingClientRect().width;
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      let newWidth;
      do {
        await sleepMs(100);
        newWidth = text.getBoundingClientRect().width;
      } while (newWidth < 0 || newWidth === originalWidth)
      let response = await fetch(
        testURI("ctr", "font", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
              
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same 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

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

read: async (key) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      let iframeLoadPromise = new Promise((resolve, reject) => {
        iframe.addEventListener("load", resolve, {once: true});
      });
      let address = testURI("resource", "page", key);
      iframe.src = address;
      await iframeLoadPromise;
      let response = await fetch(
        testURI("ctr", "page", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
image cache
Caching of images in web browsers is a standard behavior. But if that cache leaks between websites, it can be abused for cross-site tracking.
              
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 2, 2, 2, 2

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same 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

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      img.addEventListener("load", () => resolve(key), {once: true});
      img.src = testURI("resource", "image", key);
    })

read: async (key) => {
      let img = document.createElement("img");
      document.body.appendChild(img);
      let imgLoadPromise = new Promise((resolve, reject) => {
        img.addEventListener("load", resolve, {once: true});
      });
      img.src = testURI("resource", "image", key);
      await imgLoadPromise;
      let response = await fetch(
        testURI("ctr", "image", key), {"cache": "reload"});
      return (await response.text()).trim();
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
indexedDB
The IndexedDB API exposes a transactional database to web pages. That database can be used to track users across websites, unless it is partitioned.
              
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

result, different session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

result, different session: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

result, different session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

unsupported: false, false, false

passed: false, false, false

test failed: 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: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p,
960952de-fbd6-4278-85f0-c562117c1b2c_1p,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p,
3d908420-2f5e-44f6-a751-14480e05325b_1p,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_1p

result, different session: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p,
960952de-fbd6-4278-85f0-c562117c1b2c_1p,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p,
3d908420-2f5e-44f6-a751-14480e05325b_1p,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16_1p,
c7a7c812-94af-406a-b0f4-a3e96ac970f5_1p,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd_1p,
266fad2e-6322-4934-8fa0-1414fb15087c_1p

result, different session: undefined

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same session: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51_1p,
670402ab-7c8e-498e-a2fc-412775b7bcd8_1p,
bdd23153-2777-4dfe-839b-53c83748e0a7_1p,
541a2489-bb99-46aa-a401-167bf5f8f9e3_1p,
1c747676-e705-48b0-b808-613ddbd9f42e_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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

result, different session: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same session: 
e76bfdd1-0491-4b90-b570-3868442520c4_1p,
1eca2786-e863-40a4-aa45-8b3d77537dd3_1p,
bca01b74-5bc7-4b7a-9e37-c83bb8833959_1p,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5_1p,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3_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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020_1p,
5bac69f9-2e81-4d64-8833-116de9ad280b_1p,
9b9b853c-fb5e-4113-9bc7-5324994c3313_1p,
61bcf04a-8b1c-4354-b756-c6aded26aa47_1p,
6958e9c5-1694-469a-88ea-e72d4b5bb2af_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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

result, different session: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: async (secret) => {
      try {
        return await IdbKeyVal.set("secret", secret);
      } catch (e) {
        throw new Error("Unsupported");
      }
    }

read: () => IdbKeyVal.get("secret")

result, same session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

result, different session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
localStorage
The localStorage API gives websites access to a key-value database that will remain available across visits. If the localStorage API is not partitioned or blocked, it can also be used to track users across websites.
              
Failed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

result, different session: 
3fce2098-7e9d-4ba9-b078-272e478188d5_1p,
96e35e8b-83e3-40bb-90b2-81254058442a_1p,
42faff19-a4d5-4440-8137-9f83240f2c24_1p

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

result, different session: 
615467f4-5b59-4ebb-a5f7-eced31718e7f_1p,
8d0209a9-77a1-45f6-a4b5-a9584894699d_1p,
1d5f5063-ff3c-4279-be0f-6dfede562600_1p,
376bcea2-2ac1-40b3-918e-4e8e864e1535_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

result, different session: 
006e8a38-27a7-4344-8f7d-a5eb4d93f008_1p,
d1f11452-ef14-4b18-9359-f76b7ebf1e79_1p,
b5df093b-83a0-4796-9013-592159fae4bb_1p

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p,
960952de-fbd6-4278-85f0-c562117c1b2c_1p,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p,
3d908420-2f5e-44f6-a751-14480e05325b_1p,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_1p

result, different session: 
95329b24-dd1c-4e1a-aceb-23514fa75612_1p,
960952de-fbd6-4278-85f0-c562117c1b2c_1p,
513eaf28-ece4-412a-8b4f-4c6ec782bee8_1p,
3d908420-2f5e-44f6-a751-14480e05325b_1p,
74f635c4-6e5d-46d5-86e6-7c65b75369f1_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: 
b3e158a6-9ff3-4bc0-aff8-a970bc973d16_1p,
c7a7c812-94af-406a-b0f4-a3e96ac970f5_1p,
76f05b0a-7992-4450-ac2c-381b0cd8a0cd_1p,
266fad2e-6322-4934-8fa0-1414fb15087c_1p

result, different session: , , , 

unsupported: false, false, false, false

passed: true, true, true, true

test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
a0266c8c-ac70-40f9-b11c-d8dfbecdee51_1p,
670402ab-7c8e-498e-a2fc-412775b7bcd8_1p,
bdd23153-2777-4dfe-839b-53c83748e0a7_1p,
541a2489-bb99-46aa-a401-167bf5f8f9e3_1p,
1c747676-e705-48b0-b808-613ddbd9f42e_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: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

result, different session: 
55369d9a-dab8-4cc6-98eb-7c9d26ab67e3_1p,
7316f7c1-21e6-4136-b8c1-6c1265ad71ef_1p,
ab0df867-a081-4ab7-9441-fdccaa9a7aab_1p,
337c4058-1e91-4e08-980e-c55996dae7a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Passed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
e76bfdd1-0491-4b90-b570-3868442520c4_1p,
1eca2786-e863-40a4-aa45-8b3d77537dd3_1p,
bca01b74-5bc7-4b7a-9e37-c83bb8833959_1p,
8fcc1e87-1c8f-49cf-8d7d-a5fd8549c9e5_1p,
2c4d0e0f-0ec1-4e60-b91c-2f28c07baed3_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: 
5fb5e7f6-0bc9-4b98-bca2-5b9d8ee93020_1p,
5bac69f9-2e81-4d64-8833-116de9ad280b_1p,
9b9b853c-fb5e-4113-9bc7-5324994c3313_1p,
61bcf04a-8b1c-4354-b756-c6aded26aa47_1p,
6958e9c5-1694-469a-88ea-e72d4b5bb2af_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: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

result, different session: 
4c38ebec-4414-4b26-9494-20bc35ae55be_1p,
c9631ac6-c811-4462-b6b6-7df4aa91b25b_1p,
d26db7a4-f75e-4d0a-80aa-6d34dd1f9df2_1p,
b3a4e711-f75e-4c0b-be54-f0882233165b_1p,
cb9ef23b-e192-4ab1-afcd-92fedc6d4cd6_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Failed
write: (secret) => localStorage.setItem("secret", secret)

read: () => localStorage.getItem("secret")

result, same session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

result, different session: 
f2f031ec-3fda-40df-bf47-ba901a076318_1p,
68136c5b-37e8-4e21-ae51-67439b43e4c0_1p,
1b14187b-5343-4343-9cbe-a884e4b82b0a_1p,
76037bad-07bc-410e-a311-7fbf2b5787a5_1p

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
prefetch cache
A <link rel='prefetch'...> suggests to browsers they should fetch a resource ahead of time and cache it. But if browsers don't partition this cache, it can be used to track users across websites.
              
Failed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 1, 1, 1, 1

result, different session: 1, 1, 1, 1

unsupported: false, false, false, false

passed: false, false, false, false

test failed: false, false, false, false
Failed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 1, 1, 1

result, different session: 1, 1, 1

unsupported: false, false, false

passed: false, false, false

test failed: false, false, false
Failed
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 1, 1, 1, 2, 1

result, different session: 1, 1, 1, 2, 1

unsupported: false, false, false, false, false

passed: false, false, false, 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 session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true

passed: undefined

test failed: false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Failed
write: 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: 2, 1, 2, 1

result, different session: 3, 1, 2, 1

unsupported: false, false, false, false

passed: true, false, false, false

test failed: false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
Unsupported
write: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      return key;
    }

read: async (key) => {
      let link = document.createElement("link");
      link.rel = "prefetch";
      link.href = testURI("resource", "prefetch", key);
      document.getElementsByTagName("head")[0].appendChild(link);
      await sleepMs(500);
      let response = await fetch(
        testURI("ctr", "prefetch", key), {"cache": "reload"});
      let countString = (await response.text()).trim();
      if (parseInt(countString) === 0) {
        throw new Error("No requests received");
      }
      return countString;
    }

result, same session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received