Nightly Builds

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brave
1.64
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chrome
123.0
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duckduckgo
1.58
edge logo
edge
123.0
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firefox
124.0a1
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opera
108.0
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safari
17.4
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tor
13.5a4
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vivaldi
6.6
State Partitioning testsWhich browsers isolate websites to prevent them from sharing data to track you?
A common vulnerability of web browsers is that they allow tracking companies to 'tag' your browser with some data ('state') that identifies you. When third-party trackers are embedded in websites, they can see this identifying data as you browse to different websites. Fortunately, it is possible for this category of leaks to be fixed by partitioning all data stored in the browser such that no data can be shared between websites.
        
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
              
Passed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

result, different first party: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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
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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

result, different first party: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

result, different first party: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

result, different first party: 
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
47a37c68-eb39-4765-8686-ffe721bfeb14,
47a37c68-eb39-4765-8686-ffe721bfeb14,
47a37c68-eb39-4765-8686-ffe721bfeb14,
47a37c68-eb39-4765-8686-ffe721bfeb14,
47a37c68-eb39-4765-8686-ffe721bfeb14

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_http,
0a838421-59e6-4ce3-b6f3-42e934531656_http,
823d78e7-647a-4fcc-b57a-f41d088c0b37_http,
0a860175-c009-46be-9961-2b46a37d8855_http,
39583853-6411-4656-8308-d5458f074429_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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_http,
d2b09752-b8d6-44ec-8c87-08334be85367_http,
d5c24430-61df-4b85-a66a-f778ad3a0627_http,
a54c15ec-a80d-4bef-852c-fd3333e3e985_http,
a464a713-5a56-465a-8267-ca5ad5d3026e_http

result, different first party: 
18c363dd-0a25-4118-829e-68797f7cfc6a_http,
d2b09752-b8d6-44ec-8c87-08334be85367_http,
d5c24430-61df-4b85-a66a-f778ad3a0627_http,
a54c15ec-a80d-4bef-852c-fd3333e3e985_http,
a464a713-5a56-465a-8267-ca5ad5d3026e_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_http,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_http,
bedf8903-91f7-40b4-8861-2c4b4775a480_http,
371b933a-76db-4bbc-9e87-1412fb103b38_http,
ab884d29-7e62-4f69-92a5-db18d7f430a7_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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_http,
878d6152-cf5f-4045-a81a-61fca23589b1_http,
1a8c0f62-e575-49aa-82fa-2368af206f33_http,
a48844cb-5790-4cad-985f-2ac5903cf4ba_http,
e8362b3c-457f-433a-a634-b3976f2bd2e4_http

result, different first party: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_http,
878d6152-cf5f-4045-a81a-61fca23589b1_http,
1a8c0f62-e575-49aa-82fa-2368af206f33_http,
a48844cb-5790-4cad-985f-2ac5903cf4ba_http,
e8362b3c-457f-433a-a634-b3976f2bd2e4_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_http,
e910db86-3295-44ea-b0f2-141d7f682f05_http,
47ca2b25-08e4-4e73-8292-842ad34ea27f_http,
e323919e-01ad-4713-a0e0-12788b8af39d_http,
c28c0205-1252-4812-8dc8-8eea3305b475_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_http,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_http,
3bbb2028-30ca-4b99-85f6-629bc53932d8_http,
076272c4-4fc2-4104-b0e2-ce78add4bf49_http,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_http

result, different first party: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_http,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_http,
3bbb2028-30ca-4b99-85f6-629bc53932d8_http,
076272c4-4fc2-4104-b0e2-ce78add4bf49_http,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
39f3f39d-d02f-4680-b741-1d671b6882b0_http,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_http,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_http,
67ea507f-14e7-4a39-bbe0-c353019d4b23_http,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256_http,
ed41193b-a91d-4cd0-81ab-8a8854107c30_http,
b43ed285-eb5d-4a40-9aa9-116344b081fa_http,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b_http,
b61627e3-6f32-4eaf-860d-525162a2467b_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: 
2e858d0b-2216-4032-82b9-582d55d00118_http,
f3ce28e1-94bf-4b32-8a67-199a702faac3_http,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_http,
683773c8-9430-4736-aec3-80fc0b910969_http,
f5e61287-ae53-4839-9876-c35d92b94f02_http

result, different first party: 
2e858d0b-2216-4032-82b9-582d55d00118_http,
f3ce28e1-94bf-4b32-8a67-199a702faac3_http,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_http,
683773c8-9430-4736-aec3-80fc0b910969_http,
f5e61287-ae53-4839-9876-c35d92b94f02_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_js,
0a838421-59e6-4ce3-b6f3-42e934531656_js,
823d78e7-647a-4fcc-b57a-f41d088c0b37_js,
0a860175-c009-46be-9961-2b46a37d8855_js,
39583853-6411-4656-8308-d5458f074429_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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_js,
d2b09752-b8d6-44ec-8c87-08334be85367_js,
d5c24430-61df-4b85-a66a-f778ad3a0627_js,
a54c15ec-a80d-4bef-852c-fd3333e3e985_js,
a464a713-5a56-465a-8267-ca5ad5d3026e_js

result, different first party: 
18c363dd-0a25-4118-829e-68797f7cfc6a_js,
d2b09752-b8d6-44ec-8c87-08334be85367_js,
d5c24430-61df-4b85-a66a-f778ad3a0627_js,
a54c15ec-a80d-4bef-852c-fd3333e3e985_js,
a464a713-5a56-465a-8267-ca5ad5d3026e_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 first party: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_js,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_js,
bedf8903-91f7-40b4-8861-2c4b4775a480_js,
371b933a-76db-4bbc-9e87-1412fb103b38_js,
ab884d29-7e62-4f69-92a5-db18d7f430a7_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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_js,
878d6152-cf5f-4045-a81a-61fca23589b1_js,
1a8c0f62-e575-49aa-82fa-2368af206f33_js,
a48844cb-5790-4cad-985f-2ac5903cf4ba_js,
e8362b3c-457f-433a-a634-b3976f2bd2e4_js

result, different first party: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_js,
878d6152-cf5f-4045-a81a-61fca23589b1_js,
1a8c0f62-e575-49aa-82fa-2368af206f33_js,
a48844cb-5790-4cad-985f-2ac5903cf4ba_js,
e8362b3c-457f-433a-a634-b3976f2bd2e4_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 first party: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_js,
e910db86-3295-44ea-b0f2-141d7f682f05_js,
47ca2b25-08e4-4e73-8292-842ad34ea27f_js,
e323919e-01ad-4713-a0e0-12788b8af39d_js,
c28c0205-1252-4812-8dc8-8eea3305b475_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_js,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_js,
3bbb2028-30ca-4b99-85f6-629bc53932d8_js,
076272c4-4fc2-4104-b0e2-ce78add4bf49_js,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_js

result, different first party: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_js,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_js,
3bbb2028-30ca-4b99-85f6-629bc53932d8_js,
076272c4-4fc2-4104-b0e2-ce78add4bf49_js,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_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 first party: 
39f3f39d-d02f-4680-b741-1d671b6882b0_js,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_js,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_js,
67ea507f-14e7-4a39-bbe0-c353019d4b23_js,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256_js,
ed41193b-a91d-4cd0-81ab-8a8854107c30_js,
b43ed285-eb5d-4a40-9aa9-116344b081fa_js,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b_js,
b61627e3-6f32-4eaf-860d-525162a2467b_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: 
2e858d0b-2216-4032-82b9-582d55d00118_js,
f3ce28e1-94bf-4b32-8a67-199a702faac3_js,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_js,
683773c8-9430-4736-aec3-80fc0b910969_js,
f5e61287-ae53-4839-9876-c35d92b94f02_js

result, different first party: 
2e858d0b-2216-4032-82b9-582d55d00118_js,
f3ce28e1-94bf-4b32-8a67-199a702faac3_js,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_js,
683773c8-9430-4736-aec3-80fc0b910969_js,
f5e61287-ae53-4839-9876-c35d92b94f02_js

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

result, different first party: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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
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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

result, different first party: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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
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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

result, different first party: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same first party: 
fake_4955448968326257,
fake_6959127229906881,
fake_9370964934690607,
fake_9988070993202023,
fake_5819986375168003

result, different first party: 
fake_8265617188584939,
fake_9111554912396223,
fake_11903710519015509,
fake_2806035745800137,
fake_0560497645281699

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_7049171523030628,
fake_007132243038325159,
fake_6112365042903911,
fake_7589413515713641,
fake_7914710922564916

result, different first party: 
fake_9374104220941144,
fake_05985329850549315,
fake_7057445742366897,
fake_6072658183207575,
fake_8548947628009596

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_09842305085817338,
fake_27462960679821813,
fake_012013489111714293,
fake_35088983052253564,
fake_8038877028693392

result, different first party: 
fake_007071071483020663,
fake_8607316159026583,
fake_5733328111446399,
fake_4813448078796094,
fake_8832466803850452

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_05251143737470354,
fake_8957947832570639,
fake_3494066885176337,
fake_018366343768196014,
fake_3201616523475148

result, different first party: 
fake_5067678704730088,
fake_041691730200927424,
fake_24381699049628258,
fake_7474886880664768,
fake_5813990540775587

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_11599832682834443,
fake_668042402061223,
fake_45564250122528294,
fake_10068129062809184,
fake_4229572837114184

result, different first party: 
fake_1154661012492737,
fake_9989027222925042,
fake_9298805616878802,
fake_8052885011799245,
fake_3368184187742942

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_7493374263699231,
fake_4376285186962261,
fake_9979944365771523,
fake_3074867450961136,
fake_6421409363766586

result, different first party: 
fake_8609864339899984,
fake_4655837394226625,
fake_738114552083764,
fake_8095400576640068,
fake_8726114923911195

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_7853229642164867,
fake_43278034150940203,
fake_9775001282534062,
fake_8221250821691033,
fake_36583282987658094

result, different first party: 
fake_567892645185996,
fake_19591842949596594,
fake_8109242556256213,
fake_45342651084821806,
fake_18900835620605916

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_41598332473357824,
fake_2373945548670826,
fake_7640339998315031,
fake_29047932765370943,
fake_8757142227627974

result, different first party: 
fake_3626922495421583,
fake_6648877694744999,
fake_4196754272548031,
fake_8566203188211376,
fake_49287997385888827

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_2540317682130313,
fake_8355021706019448,
fake_09414249582374579,
fake_7814975712582657,
fake_9715373293567138

result, different first party: 
fake_4274563208909532,
fake_8959708028332292,
fake_6667148850955893,
fake_6977341780757016,
fake_13285109880186363

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

result, different first party: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
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, 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: 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
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: , , , , 

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: , , , , 

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
898f1764240d66343b3f8476efd1815b,
ba3ccdebb7d36cdf2c8218b077111406,
377064007369325a55371dd64fe3661c,
a76a532fc854660c0839473bc72e0c78,
42e0338ee43852a707ccc6eea47f2174

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: 
7e2b9f08b1a63a56a254fb8f9d9d685c,
d19171734567f09ca0751a96a765de8e,
e3701f4fb260c4f7c9e2addba1ed5fb7,
08201cfdebd45835244a50ebe87c1a2b,
6caea0ef4265590bed68b0e6cef1ddaa

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: , , , , 

result, different first party: , , , , 

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same first party: 
61fac741f8f9ffd2ba490556fc927b75,
7e1a21836ee138532f14b823b7acaa92,
fd3cbee6001d21c59519689d8a6f5034,
00aac338585034953430fb3f082a3357,
3e90d0d07b031731b524d0875c8380c5

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: 
85ea6d5dfb19a28b721d1e06b03c78d6,
0f73d064eeefd1eaa8ded4545bd14e6f,
9ea2aba88f1b7abf99f7cb013eaa9a26,
030cd554ee25c384f421f2e074b05a30,
a85ab1c7a72ee31cae2236579fbd3925

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: 
bc4b8d1cd00c91dbeb6134c6ec6e02a3,
accc1cd08dd833c461f5af02b58db769,
ef966c4157235c2ea2215f341947480f,
c43b7f3343bf3d60218957c6765ae9be,
8828a846b9a6ce6849d029acd6d311ea

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: , , , , 

result, different first party: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
e4cc26012cafbb10bb87ace6cbfb6d51,
fb030293f03f3bef774bfc28754c3597,
6ee2dd5f4eae898ffef6db4263c15ac8,
8288f3953e268299bcd4a0a42910baa9,
a9c23d371d49e078c7769a315d52b07c

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: read HSTS flag

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

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

unsupported: false, false, false, , false

passed: true, true, true, true, true

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: read HSTS flag

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

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

unsupported: false, false, false, , false

passed: true, true, true, true, true

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

read: read HSTS flag

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Passed
write: 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
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, not tested

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: null

result, same first party: , , , , 

result, different first party: 
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
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
iframe cache
An iframe is an element in a web page than allows websites to embed a second web page. Caching of this web page could be abused for cross-site tracking.
              
Passed
write: (key) => new Promise((resolve, reject) => {
      let iframe = document.createElement("iframe");
      document.body.appendChild(iframe);
      iframe.addEventListener("load", () => resolve(key), {once: true});
      iframe.src = testURI("resource", "page", key);
    })

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
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, 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: 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
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: undefined

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same first party: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
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, 1

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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: 
<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: , , , , 

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: 
<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: , , , , 

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
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

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
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: 
a73bd157676d117d0abf95dd2dccc1cf50e77434a10484e70d9a57a4fc3c4caa,
a7b480b23656114421cd856c33ab94768972f4922a01800a02c7d696fc4fedc7,
e043984905a81d74c96537120af561ec551306ba05df2bfe325c1aac4d42aed4,
ade69911a9bb57fd73dcec9ff891163fa584b6ac53657fe6af112cffb440adf3,
c70c243c365e28581dc87dbbd5baf9316320c2de4e03a980e481f8422ca2fded

result, different first party: 
c4434cf593bcbd85d99aed2e331074c59f2a84c55057bcd3b44e202280b82e5e,
6e7204089bd760b6426ebb49b4ca3e124bbdfc3fb426a7041198df9d03dc4226,
d026b89c194e3ee9fbfa0e0be2226d08767ea2453b4d702b6189230c643bffc1,
dabc6d26d9a0c399f2e121c38cadbdde7bcd0323cb5cf0846e423fbf0f804aaf,
1bd82db7bb11b6a7ba6a51f0d3a78f37dccdb1ed06ac3483a3d81f60e42bc34a

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: 
a28021b16f1dcad4882f7ef6fce7fe22b06d6ca0770ad11d2667492532b0eba7,
b68bf706108854d1f6705bc48f681cd95e43d53c1f561195c1d30832cbb878e3,
bdf22236c3715509f685b77c6f7e0c552e138b5d35d4401d2ba03cb3561a8c09,
200bad9393864c91d4f523fc5ba0f70060809e547c329b72499ad22ffa1ee9d7,
04df09b20894c9d4576960f99a08590b066281ee4a05dd32b925a48d553a9217

result, different first party: 
8ca11da3d0f24a1aa0a168790c4a1d31cb0df28cd7038ca1da404608a8ec9df2,
01d6e23ca74eafa5e7f2a9f6dec53803f170bff56c8dddb9e7fd059a3273c20a,
badf3fcff507d49a6ae056e00adfa551c7ca439addf6226b8fdf55f13e0dfa63,
e1397853592eb6e841af9ddd21160cd32e6613f276c3dd79247adf512accfbc1,
2539cc3e34f292e6a777199c338be02e781f4b29051201ff99ef564292d7432c

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: 
3da6056d6f90e2e122b9ee045b054e0df940288961570eb86a3b4fb76017d9cb,
48e5fd2bf4d1dfc34f3e05cd0fb1cda7823b8eba1b62037cc603e33b4bb40815,
bc75187656f3225f5559c9f007334ba32cfb0e1b555aa9c06e84b07e38fdb73f,
e058fd3fe36d2a76c355bddeae9d121693432a500f2f403397a2fc22538e689c,
29f760f8bff5b11db7f1a821279156ed812155638097c0e9b608375c0dfdb31f

result, different first party: 
f8588fa2cc7b5134616331ad702126fbd464dad08c1b7771f4275d1f2b839b2b,
03297732cfc77ac1578e9c1ce0aaf8e954962698f74c6f7078ef710f66acb2ae,
74b0e9ffb7ec4d751b16326abc247a79e84ac333b656fbbb028c007a6c548cfc,
d6a1f11b97e1c08950da0aa7e04173a629e412e9c888fbaf03df899dbe193536,
f81b18823e61eef8d39858c3f723a7e4c7d44baa211ca571af73371cd2954acf

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: 
fe98ce9232de8e249643ea22fd412fada7ede3c0fa9e56b36e48496900ee2831,
a7ec2e04cfe4418acbe69a30f07519a14e5b4f9673d45fe414eafc21b8937ff1,
f10476d2c5b2f415f04eb75803b6abdec6094283b9b928b082bca1129bf69257,
ee7021a65ce5b293d1ef37df91ce1e14f925b631735cee0f2365046ee49c433d,
7233533195307a2888a0d9c9e8ebaa12985841805a4577ad6d401db0a5c17c89

result, different first party: 
7d6f7ce6ec6353445ea91aa3c9125bb3f9af808532ecf8371a7d3ec9eabd8f88,
5b2ac71a45297f8da69d55a468562499abc20b1aced94ce94db7dc61b77d3ee1,
b79fa9f3c33ec1b44f44e6941b7cce3626cde838bb4eacf3384751cd52a79453,
f866ce601239a8dc7e2edab81623497090306693d3c11302694b28d92810b749,
279fd5309627646df70abd54957ad59238506f8905a29a119a092f9a9b10d28a

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: 
cec75588ef4795402e87c4063a37104ee010532a9c1f24b1d012a210ffeced5b,
aa7f7d9b03321a3540590a65299f926002d36054127ad3efba4351d5bf264645,
0755e6d2c8366a260c5614e580dfd4372fd65860eda88606e5b52b3bca9747bc,
9fd6b21c02cf42e3ffa17c1d4ff631e7c8855ab1cdae3d1a3a7784ae61394d6b,
038ae889681013412b96f0b2869c1c5c5c5d80f9724d3f6c9b9c1c373f8dafa3

result, different first party: 
29a6fe146e2d3807d9f2dc2a072a04246f1906bcd45baa3657017d084dd84fce,
b6447792562e0b2594ba74f44622325651cb60ce9226095ac5da29578cb3d0ed,
d998bb53bdf9f12d714fa5a736ebebfd772762aac8388ac3e14fcf1820bd98cd,
b527e15c90a970e504ca09165183580fe6bb6acd958bda8260a3870bac055bcd,
c51c4b2c7d5843e66f97c908848406b50e308842ba23c9fdf8e2ab873f800d23

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: 
f8f9bebf99d8fe7f01966d5887ef2abc0f05b573673d4f934fed3356b29f6630,
8527abc526a078616d120882003761aa5edd5743b653ab8fcbb82861da988e8b,
867924fa90a0504220dfdb9d6ae828da07e0f93b4edb68b335f8e04c19458019,
86ae4b7b00b6b3e8fded452978cde15c4580b4052d602fc03a4f76487b7e1862,
e642c9ac62f745ae76a0e1dc50559954571d041cd1d2cd84baad07e4f055d750

result, different first party: 
d02ea228328f0f40780e395e4257d31754cb93567595f72cbf6ccfe1b3b4bb0b,
3ab418c698047180f4e45f8a6923902d93ea9384ca3ec6df7f84dd91a681477f,
33d3bff422a2280b2acedede3decd0489021f13344ed519e2510d17a7f8a4231,
1e154fba9644c9f1f27ac69f29e2985acfb639b21569c90adc06da95263262c1,
ccb3296d67f814bd76183ba431a519a7f2e901fb9395a6db53fdc2b7afc1b24b

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: 
c5676b5d0e106c8520c8f46254d55b4f4bf3d013783a69268e489e9dd3b0cf32,
385bcb78bd71728f0ed352c164a26cda3fac8251152229b44fae41d259660abe,
a5de8f5932a17451e812c3816522995fbbfec4c010faa75731e57a80e0582896,
9dedaf56fe9796f61b52ce27433bbe91dbf230f91603ab9805a89ba74c1724d0,
da9da7bdef38bba6d75c496271887652bcc9bdaf0339d205276f7216978113ca

result, different first party: 
2d4b08e8b776e7d032dcac56703c2a699e2c16a122ca811a89293c1500271a64,
eb803b0f1f0db03b5535f60018ff7ca53292f08d51653a8715772df474dfb39b,
2b51dcfaa9490c7554b19410f5be8879ff41cfa2b96644432a4484a07383bd83,
fe16a8e76ad84d42b21bc9c9b461eeca8206bf829ae8059d650926b7ff3654ba,
97438f945a03f3846d356a080277463820f26d701f48e49184a08532a6c92f3e

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: 
91b47f47c3b3dad5156fcb7a0045df14bb1db8b0204a83b401ac59cf238afb2a,
0daeb27b03e1f6904761cb506b2f168a4d59830dbc29d6c8b905d965137152f8,
6d6c5087e806e4a377acd603d693e804e3c4d70d90684627a9c7c83917d1c64f,
f13a14881e9f18ac0a5360539ea11e531e7b77e26566908cddc964a67c4fbbf3,
b653682c10a3d8703b1c3709248b22d4e421f007b87a9f286d0daa50e0b8c8d7

result, different first party: 
df67859b18858f06fc2edf74f6612aba32915af3938eb9d13fd264046b4f1cf6,
77fd2ce274fbce596b1dadcaf3100848a185abcae84c0f755610cc2c1f0af873,
b0d16f03c34678b13cf55bb682bdeeaa21909eb4f0dbb221022fcc66f3afeb2b,
f16691181528ae3ece80753b8b1c1dc6d8b757b856b9cd6998b0096ff3feb278,
9b5f5b349798066b19ffb985bd9f431e68c2e578bdcc6bd58484008c6b5534ea

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: 
a16052cd56c34c692954097005c943aa745edf1b6a635e8671b804ee94ebf0b1,
92ee14b5d5448ccfbfd7e5ba395d535b203beb0239ed21dc5dae68253883723c,
74818cfdd1360e23143f76761e5fee1ed7e8b97c4e3c0c81f341aa0222616acc,
5e89a4f20112f3d443a91829de52ea18a1354b9a2cd5162a3066da1de3c7bbe9,
9d2fa2563c228fbd246c13d45e9e6d6939a2c903a68b77c961bc0afe5ca2a40a

result, different first party: 
a2046c2dd143ecc9d3f8150ca9b4cd5439aff25721926fb709cc4c4961f58ad6,
2e53864b1f6b5072d1fec23fdca074e136257dbf659813bfbdddc984fe2f758d,
7e4c8aa4e27f1816b1fd98717c185fc4acef26fe6c30a367c097ad9a62023628,
7a937286afd27a3ea6ea9ccb616023fa7ee9719d88cf3cf728acd88970928ad2,
8181c553605409181077419eb6a5d81cf462cd78f6f9a7233ee05939e8579b9f

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
              
Passed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => document.referrer

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

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

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe,
0a838421-59e6-4ce3-b6f3-42e934531656,
823d78e7-647a-4fcc-b57a-f41d088c0b37,
0a860175-c009-46be-9961-2b46a37d8855,
39583853-6411-4656-8308-d5458f074429

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a,
d2b09752-b8d6-44ec-8c87-08334be85367,
d5c24430-61df-4b85-a66a-f778ad3a0627,
a54c15ec-a80d-4bef-852c-fd3333e3e985,
a464a713-5a56-465a-8267-ca5ad5d3026e

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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4,
3e1a9d99-b563-44cc-bd40-965f1cfe1921,
bedf8903-91f7-40b4-8861-2c4b4775a480,
371b933a-76db-4bbc-9e87-1412fb103b38,
ab884d29-7e62-4f69-92a5-db18d7f430a7

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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
878d6152-cf5f-4045-a81a-61fca23589b1,
1a8c0f62-e575-49aa-82fa-2368af206f33,
a48844cb-5790-4cad-985f-2ac5903cf4ba,
e8362b3c-457f-433a-a634-b3976f2bd2e4

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
e910db86-3295-44ea-b0f2-141d7f682f05,
47ca2b25-08e4-4e73-8292-842ad34ea27f,
e323919e-01ad-4713-a0e0-12788b8af39d,
c28c0205-1252-4812-8dc8-8eea3305b475

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
3bbb2028-30ca-4b99-85f6-629bc53932d8,
076272c4-4fc2-4104-b0e2-ce78add4bf49,
56c106e2-16d0-436c-84de-6c9b6acfb3ef

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: 
39f3f39d-d02f-4680-b741-1d671b6882b0,
d8848dcb-7e19-4775-91d7-9c6c13e052ba,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
67ea507f-14e7-4a39-bbe0-c353019d4b23,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256,
ed41193b-a91d-4cd0-81ab-8a8854107c30,
b43ed285-eb5d-4a40-9aa9-116344b081fa,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
b61627e3-6f32-4eaf-860d-525162a2467b

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: 
2e858d0b-2216-4032-82b9-582d55d00118,
f3ce28e1-94bf-4b32-8a67-199a702faac3,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
683773c8-9430-4736-aec3-80fc0b910969,
f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

read: () => window.name

result, same first party: 
name_85b9c2dc-4a3c-44ae-bb14-17c759676afe,
name_0a838421-59e6-4ce3-b6f3-42e934531656,
name_823d78e7-647a-4fcc-b57a-f41d088c0b37,
name_0a860175-c009-46be-9961-2b46a37d8855,
name_39583853-6411-4656-8308-d5458f074429

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_18c363dd-0a25-4118-829e-68797f7cfc6a,
name_d2b09752-b8d6-44ec-8c87-08334be85367,
name_d5c24430-61df-4b85-a66a-f778ad3a0627,
name_a54c15ec-a80d-4bef-852c-fd3333e3e985,
name_a464a713-5a56-465a-8267-ca5ad5d3026e

result, different first party: 
name_18c363dd-0a25-4118-829e-68797f7cfc6a,
name_d2b09752-b8d6-44ec-8c87-08334be85367,
name_d5c24430-61df-4b85-a66a-f778ad3a0627,
name_a54c15ec-a80d-4bef-852c-fd3333e3e985,
name_a464a713-5a56-465a-8267-ca5ad5d3026e

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => window.name

result, same first party: 
name_125432da-5470-4bd9-a28c-e1fe7247a5e4,
name_3e1a9d99-b563-44cc-bd40-965f1cfe1921,
name_bedf8903-91f7-40b4-8861-2c4b4775a480,
name_371b933a-76db-4bbc-9e87-1412fb103b38,
name_ab884d29-7e62-4f69-92a5-db18d7f430a7

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_a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
name_878d6152-cf5f-4045-a81a-61fca23589b1,
name_1a8c0f62-e575-49aa-82fa-2368af206f33,
name_a48844cb-5790-4cad-985f-2ac5903cf4ba,
name_e8362b3c-457f-433a-a634-b3976f2bd2e4

result, different first party: 
name_a386e0c1-6f89-4aea-8a13-12def4c0c9c3,
name_878d6152-cf5f-4045-a81a-61fca23589b1,
name_1a8c0f62-e575-49aa-82fa-2368af206f33,
name_a48844cb-5790-4cad-985f-2ac5903cf4ba,
name_e8362b3c-457f-433a-a634-b3976f2bd2e4

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => window.name

result, same first party: 
name_b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6,
name_e910db86-3295-44ea-b0f2-141d7f682f05,
name_47ca2b25-08e4-4e73-8292-842ad34ea27f,
name_e323919e-01ad-4713-a0e0-12788b8af39d,
name_c28c0205-1252-4812-8dc8-8eea3305b475

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_2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
name_f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
name_3bbb2028-30ca-4b99-85f6-629bc53932d8,
name_076272c4-4fc2-4104-b0e2-ce78add4bf49,
name_56c106e2-16d0-436c-84de-6c9b6acfb3ef

result, different first party: 
name_2e9cedda-c768-4af8-ae44-7cf9a6cd99ed,
name_f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b,
name_3bbb2028-30ca-4b99-85f6-629bc53932d8,
name_076272c4-4fc2-4104-b0e2-ce78add4bf49,
name_56c106e2-16d0-436c-84de-6c9b6acfb3ef

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

read: () => window.name

result, same first party: 
name_39f3f39d-d02f-4680-b741-1d671b6882b0,
name_d8848dcb-7e19-4775-91d7-9c6c13e052ba,
name_8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68,
name_67ea507f-14e7-4a39-bbe0-c353019d4b23,
name_ce970a34-89ee-4cec-bee1-9fd5fb8a661f

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_3e64ad26-ab88-4553-aa54-2d649cd1c256,
name_ed41193b-a91d-4cd0-81ab-8a8854107c30,
name_b43ed285-eb5d-4a40-9aa9-116344b081fa,
name_6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b,
name_b61627e3-6f32-4eaf-860d-525162a2467b

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_2e858d0b-2216-4032-82b9-582d55d00118,
name_f3ce28e1-94bf-4b32-8a67-199a702faac3,
name_f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
name_683773c8-9430-4736-aec3-80fc0b910969,
name_f5e61287-ae53-4839-9876-c35d92b94f02

result, different first party: 
name_2e858d0b-2216-4032-82b9-582d55d00118,
name_f3ce28e1-94bf-4b32-8a67-199a702faac3,
name_f7e83b2d-cbcf-4099-bf46-0172410c0a0a,
name_683773c8-9430-4736-aec3-80fc0b910969,
name_f5e61287-ae53-4839-9876-c35d92b94f02

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
HTTPS testsWhich browsers prevent unencrypted network connections?
HTTPS is the protocol that web browsers use to connect securely to websites. When HTTPS is being used, the connection is encrypted so that third parties on the network cannot read content being sent between the server and your browser. In the past, insecure connections were the default and websites would need to actively request that a browser use HTTPS. Now the status quo is shifting, and browser makers are moving toward a world where HTTPS is the default protocol.`
        
Insecure website warning
Checks to see if the browser stops loading an insecure website and warns the user before giving them the option to continue. Known as HTTPS-Only Mode in some browsers.
              
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, true, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website never loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: false, false, false, false, false
result: 
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
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
Upgradable address
Checks to see if an insecure address entered into the browser's address bar is upgraded to HTTPS whenever possible.
              
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
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
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
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
Upgradable hyperlink
Checks to see if the user has clicked on a hyperlink to an insecure address, if the browser upgrades that address to HTTPS whenever possible.
              
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
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
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
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
Upgradable image
Checks to see if the browser attempts to upgrade an insecure address for an image to HTTPS whenever possible.
              
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Failed
passed: false, false, false, false, false
result: 
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Failed
passed: false, false, false, false, false
result: 
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely,
loaded insecurely
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Upgradable script
Checks to see if the browser attempts to upgrade an insecure address for an script to HTTPS whenever possible.
              
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Misc testsWhich browsers provide additional assorted privacy protections?
This category includes tests for the presence of miscellaneous privacy features
        
ECH enabled
Encrypted Client Hello (ECH) is a new protocol that hides the website you are visiting from third-party network eavesdroppers.
              
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true, true
GPC enabled first-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a website not to sell the user's personal data to third parties. This test checks to see if the GPC header is sent by default to the top-level website.
              
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
GPC enabled third-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a visited website not to sell the user's personal data to other parties. This test checks to see if the GPC header is sent to third-party elements on the web page.
              
Passed
sec-gpc: 1
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
IP address leak
IP addresses can be used to uniquely identify a large percentage of users. A proxy, VPN, or Tor can mask a user's IP address.
              
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
Stream isolation
Browsers that use Tor can use a different Tor circuit per top-level website.
              
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
      if (!usingTor) {
        throw new Error("Unsupported");
      }
    }
read: async () => {
      if (usingTor) {
        return ipAddress;
      } else {
        throw new Error("Unsupported");
      }
    }
unsupported: true, true, true, true, true
readSameFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty: 
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
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: 
2a0b:f4c2:1::1,
2a0b:f4c2:1::1,
2a0b:f4c2::15,
2605:6400:30:f7ca::2,
2001:67c:6ec:203:192:42:116:211
readDifferentFirstParty: 
2001:67c:6ec:203:192:42:116:189,
2602:fc24:13:e::1234,
2001:67c:6ec:203:192:42:116:221,
2a02:418:6017::148,
179.43.159.197
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
Tor enabled
The Tor network sends the browser's web requests through a series of relays to hide a user's IP address, thereby helping to mask their identity and location. This test checks to see if the Tor network is being used by default.
              
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
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
Fingerprinting resistance testsWhich browsers hide what's unique about your device?
Fingerprinting is a technique trackers use to uniquely identify you as you browse the web. A fingerprinting script will measure several characteristics of your browser and, combining this data, will build a fingerprint that may uniquely identify you among web users. Browsers can introduce countermeasures, such as minimizing the distinguishing information disclosed by certain web APIs so your browser is harder to pick out from the crowd (so-called 'fingerprinting resistance').`,
        
Media query screen height
Height of the user's screen in pixels.
              
Passed
expression: undefined
desired expression: undefined
actual value: 1289,1293,1291,1286,1292
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: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,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
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: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,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
Media query screen width
Width of the user's screen in pixels.
              
Passed
expression: undefined
desired expression: undefined
actual value: 1160,1160,1160,1160,1162
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: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,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
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: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,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
outerHeight
Height of the browser window in pixels, including browser chrome.
              
Passed
expression: outerHeight
desired expression: undefined
actual value: 1289,1293,1291,1286,1292
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
Passed
expression: outerHeight
desired expression: undefined
actual value: 703,703,703,703,703
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: 1040,1040,1040,1040,1040
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 1061,1061,1061,1061,1061
desired value: undefined
passed: false,false,false,false,false
Failed
expression: outerHeight
desired expression: undefined
actual value: 940,940,940,940,940
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
screen.height
Height of the user's screen, in pixels.
              
Passed
expression: screen.height
desired expression: undefined
actual value: 1289,1293,1291,1286,1292
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: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,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
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: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,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
screen.width
Width of the user's screen, in pixels.
              
Passed
expression: screen.width
desired expression: undefined
actual value: 1160,1160,1160,1160,1162
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: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,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
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: 2560,2560,2560,2560,2560
desired value: undefined
passed: false,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
screenX
Position, in pixels, of the left edge of the browser window on screen.
              
Passed
expression: screenX
desired expression: undefined
actual value: 4,7,2,0,4
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
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
Passed
expression: screenX
desired expression: undefined
actual value: 4,4,4,4,4
desired value: undefined
passed: true,true,true,true,true
Failed
expression: screenX
desired expression: undefined
actual value: 320,320,320,320,320
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screenX
desired expression: undefined
actual value: 340,340,340,340,340
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
screenY
Position, in pixels, of the top edge of the browser window on screen.
              
Passed
expression: screenY
desired expression: undefined
actual value: 8,1,6,1,1
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: 1440,1440,1440,1440,1440
desired value: undefined
passed: false,false,false,false,false
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: 25,25,25,25,25
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 202,202,202,202,202
desired value: undefined
passed: false,false,false,false,false
Failed
expression: screenY
desired expression: undefined
actual value: 500,500,500,500,500
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
System font detection
Web pages can detect the presence of a font installed on the user's system. The presence or absence of various fonts is commonly used to fingerprint users.
              
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,false,false
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false,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
Tracking query parameter testsWhich browsers remove URL parameters that can track you?
When you browse from one web page to another, tracking companies will frequently attach a 'tracking query parameter' to the address of the second web page. That query parameter may contain a unique identifier that tracks you individually as you browse the web. And these query parameters are frequently synchronized with cookies, making them a powerful tracking vector. Web browsers can protect you from known tracking query parameters by stripping them from web addresses before your browser sends them. (The set of tracking query parameters tested here was largely borrowed from Brave.)`
        
__hsfp
HubSpot tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
__hssc
HubSpot tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
__hstc
HubSpot tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
__s
Drip.com email address tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
_hsenc
HubSpot tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
_openstat
Yandex tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
dclid
DoubleClick Click ID (Google)
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
fbclid
Facebook Click Identifier
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
gclid
Google Click Identifier
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
hsCtaTracking
HubSpot tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
mc_eid
Mailchimp Email ID (email recipient's address)
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
mkt_tok
Adobe Marketo tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
ml_subscriber
MailerLite email tracking
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
ml_subscriber_hash
MailerLite email tracking
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
msclkid
Microsoft Click ID
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
oly_anon_id
Omeda marketing 'anonymous' customer id
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
oly_enc_id
Omeda marketing 'known' customer id
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
rb_clickid
Unknown high-entropy tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
s_cid
Adobe Site Catalyst tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
vero_conv
Vero tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
vero_id
Vero tracking parameter
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
wickedid
Wicked Reports e-commerce tracking
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
yclid
Yandex Click ID
              
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Failed
value: 5456301701128969
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5456301701128969
passed: false, false, false, false, false
Tracker content blocking testsWhich browsers block important known tracking scripts and pixels?
When you visit a web page, it frequently has third-party embedded tracking content, such as scripts and tracking pixels. These embedded components spy on you. Some browsers and browser extensions maintain list of tracking companies and block their content from being loaded. This section checks to see if a browser blocks 20 of the largest trackers listed by https://whotracks.me.`
        
Adobe
Tests whether the browser blocks the page from loading the tracker at https://munchkin.marketo.net/munchkin.js
              
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: false, false, false, false, false
Adobe Audience Manager
Tests whether the browser blocks the page from loading the tracker at https://dpm.demdex.net/ibs
              
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false, false
Amazon adsystem
Tests whether the browser blocks the page from loading the tracker at https://s.amazon-adsystem.com/dcm
              
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
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, false
AppNexus
Tests whether the browser blocks the page from loading the tracker at https://ib.adnxs.com/px?id=178248&t=1
              
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false, false, false, false
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, false
Bing Ads
Tests whether the browser blocks the page from loading the tracker at https://bat.bing.com/bat.js
              
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Failed
url: https://bat.bing.com/bat.js
passed: false, false, false, false, false
Chartbeat
Tests whether the browser blocks the page from loading the tracker at https://static.chartbeat.com/js/chartbeat.js
              
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false, false, false
Criteo
Tests whether the browser blocks the page from loading the tracker at https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
              
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false, false
DoubleClick (Google)
Tests whether the browser blocks the page from loading the tracker at https://securepubads.g.doubleclick.net/static/glade.js
              
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false, false, false
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, false
Facebook tracking
Tests whether the browser blocks the page from loading the tracker at https://connect.facebook.net/en_US/fbevents.js
              
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Google (third-party ad pixel)
Tests whether the browser blocks the page from loading the tracker at https://www.google.com/pagead/1p-user-list/
              
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: false, false, false, false, false
Google Analytics
Tests whether the browser blocks the page from loading the tracker at https://google-analytics.com/urchin.js
              
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false, false, false
Google Tag Manager
Tests whether the browser blocks the page from loading the tracker at https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
              
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false, false
Index Exchange
Tests whether the browser blocks the page from loading the tracker at https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
              
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
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, false
New Relic
Tests whether the browser blocks the page from loading the tracker at https://js-agent.newrelic.com/nr-1212.min.js
              
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false, false, false
Quantcast
Tests whether the browser blocks the page from loading the tracker at https://pixel.quantserve.com/pixel
              
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false, false
Scorecard Research Beacon
Tests whether the browser blocks the page from loading the tracker at https://sb.scorecardresearch.com/internal-c2/default/cs.js
              
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: false, false, false, false, false
Taboola
Tests whether the browser blocks the page from loading the tracker at https://trc.taboola.com/futureplc-tomsguide/trc/3/json
              
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Twitter pixel
Tests whether the browser blocks the page from loading the tracker at https://t.co/i/adsct
              
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Yandex Ads
Tests whether the browser blocks the page from loading the tracker at https://yandex.ru/ads/system/header-bidding.js
              
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Tracking cookie protection testsWhich browsers block important known tracking cookies?
A large fraction of web pages on the web have hidden third-party trackers that read and write cookies in your browser. These cookies can be used to track your browsing across websites. This section checks to see if a browser stops cross-site tracking by cookies from 20 of the largest trackers listed by https://whotracks.me.`,
        
Adobe
Tests whether the browser stops cookies from munchkin.marketo.net from tracking users across websites.
              
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, 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, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: true, 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, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: true, 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, false
url: https://dpm.demdex.net/ibs
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: true, 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, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, 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, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: true, 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, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, 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, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true, true
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, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true, true
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, false
url: https://bat.bing.com/bat.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, 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, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, 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, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, 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, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: true, 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, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, 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, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: true, true, true, true, true
Facebook tracking
Tests whether the browser stops cookies from connect.facebook.net from tracking users across websites.
              
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, 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, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: true, 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, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, 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, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: true, 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, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true, true
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, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true, true
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, false
url: https://google-analytics.com/urchin.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, 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, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true, true
Index Exchange
Tests whether the browser stops cookies from dsum-sec.casalemedia.com from tracking users across websites.
              
Passed
passed: true, true, true, true, 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, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, 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, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: true, 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
Failed
passed: false, 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, true
New Relic
Tests whether the browser stops cookies from js-agent.newrelic.com from tracking users across websites.
              
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, 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, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, 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, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: true, 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, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, 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, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, 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, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: true, 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, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true, true
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, false
url: https://t.co/i/adsct
cookieFound: true, true, true, true, true
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, false
url: https://t.co/i/adsct
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://t.co/i/adsct
cookieFound: true, 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, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, 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, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, 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
Failed
passed: false, false, false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: true, 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, 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, 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
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, 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, 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
Unsupported
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

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

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

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

unsupported: true, true, true, true, true

passed: undefined

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

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

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

result, different session: 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
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_1p

result, different session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_1p

result, different session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_1p,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_1p,
bedf8903-91f7-40b4-8861-2c4b4775a480_1p,
371b933a-76db-4bbc-9e87-1412fb103b38_1p,
ab884d29-7e62-4f69-92a5-db18d7f430a7_1p

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

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_1p

result, different session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p,
e910db86-3295-44ea-b0f2-141d7f682f05_1p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p,
e323919e-01ad-4713-a0e0-12788b8af39d_1p,
c28c0205-1252-4812-8dc8-8eea3305b475_1p

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p,
e910db86-3295-44ea-b0f2-141d7f682f05_1p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p,
e323919e-01ad-4713-a0e0-12788b8af39d_1p,
c28c0205-1252-4812-8dc8-8eea3305b475_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_1p

result, different session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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: Failed reading data from the file system,
Error: Failed reading data from the file system,
Error: Failed reading data from the file system,
Error: Failed reading data from the file system,
Error: Failed reading data from the file system

result, different session: 
Error: Failed reading data from the file system,
Error: Failed reading data from the file system,
Error: Failed reading data from the file system,
Error: Failed reading data from the file system,
Error: Failed reading data from the file system

unsupported: true, true, true, true, true

passed: undefined

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: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

result, different session: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p_http,
0a838421-59e6-4ce3-b6f3-42e934531656_1p_http,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p_http,
0a860175-c009-46be-9961-2b46a37d8855_1p_http,
39583853-6411-4656-8308-d5458f074429_1p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p_http,
d2b09752-b8d6-44ec-8c87-08334be85367_1p_http,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p_http,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p_http,
a464a713-5a56-465a-8267-ca5ad5d3026e_1p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_1p_http,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_1p_http,
bedf8903-91f7-40b4-8861-2c4b4775a480_1p_http,
371b933a-76db-4bbc-9e87-1412fb103b38_1p_http,
ab884d29-7e62-4f69-92a5-db18d7f430a7_1p_http

result, different session: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_1p_http,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_1p_http,
bedf8903-91f7-40b4-8861-2c4b4775a480_1p_http,
371b933a-76db-4bbc-9e87-1412fb103b38_1p_http,
ab884d29-7e62-4f69-92a5-db18d7f430a7_1p_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p_http,
878d6152-cf5f-4045-a81a-61fca23589b1_1p_http,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p_http,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p_http,
e8362b3c-457f-433a-a634-b3976f2bd2e4_1p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p_http,
e910db86-3295-44ea-b0f2-141d7f682f05_1p_http,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p_http,
e323919e-01ad-4713-a0e0-12788b8af39d_1p_http,
c28c0205-1252-4812-8dc8-8eea3305b475_1p_http

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p_http,
e910db86-3295-44ea-b0f2-141d7f682f05_1p_http,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p_http,
e323919e-01ad-4713-a0e0-12788b8af39d_1p_http,
c28c0205-1252-4812-8dc8-8eea3305b475_1p_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p_http,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p_http,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p_http,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p_http,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_1p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p_http,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p_http,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p_http,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p_http,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_1p_http

result, different session: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p_http,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p_http,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p_http,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p_http,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_1p_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
3e64ad26-ab88-4553-aa54-2d649cd1c256_1p_http,
ed41193b-a91d-4cd0-81ab-8a8854107c30_1p_http,
b43ed285-eb5d-4a40-9aa9-116344b081fa_1p_http,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b_1p_http,
b61627e3-6f32-4eaf-860d-525162a2467b_1p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
2e858d0b-2216-4032-82b9-582d55d00118_1p_http,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p_http,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p_http,
683773c8-9430-4736-aec3-80fc0b910969_1p_http,
f5e61287-ae53-4839-9876-c35d92b94f02_1p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p_js,
0a838421-59e6-4ce3-b6f3-42e934531656_1p_js,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p_js,
0a860175-c009-46be-9961-2b46a37d8855_1p_js,
39583853-6411-4656-8308-d5458f074429_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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p_js,
d2b09752-b8d6-44ec-8c87-08334be85367_1p_js,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p_js,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p_js,
a464a713-5a56-465a-8267-ca5ad5d3026e_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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_1p_js,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_1p_js,
bedf8903-91f7-40b4-8861-2c4b4775a480_1p_js,
371b933a-76db-4bbc-9e87-1412fb103b38_1p_js,
ab884d29-7e62-4f69-92a5-db18d7f430a7_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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p_js,
878d6152-cf5f-4045-a81a-61fca23589b1_1p_js,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p_js,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p_js,
e8362b3c-457f-433a-a634-b3976f2bd2e4_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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p_js,
e910db86-3295-44ea-b0f2-141d7f682f05_1p_js,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p_js,
e323919e-01ad-4713-a0e0-12788b8af39d_1p_js,
c28c0205-1252-4812-8dc8-8eea3305b475_1p_js

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p_js,
e910db86-3295-44ea-b0f2-141d7f682f05_1p_js,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p_js,
e323919e-01ad-4713-a0e0-12788b8af39d_1p_js,
c28c0205-1252-4812-8dc8-8eea3305b475_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p_js,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p_js,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p_js,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p_js,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_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: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p_js,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p_js,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p_js,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p_js,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_1p_js

result, different session: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p_js,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p_js,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p_js,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p_js,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256_1p_js,
ed41193b-a91d-4cd0-81ab-8a8854107c30_1p_js,
b43ed285-eb5d-4a40-9aa9-116344b081fa_1p_js,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b_1p_js,
b61627e3-6f32-4eaf-860d-525162a2467b_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: 
2e858d0b-2216-4032-82b9-582d55d00118_1p_js,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p_js,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p_js,
683773c8-9430-4736-aec3-80fc0b910969_1p_js,
f5e61287-ae53-4839-9876-c35d92b94f02_1p_js

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_1p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_1p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

result, same session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_1p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

result, same session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_1p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

result, same session: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
              
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_5307779021470667,
fake_4925321266698144,
fake_7097748754191378,
fake_6195382841468382,
fake_5355711442408828

result, different session: 
fake_5307779021470667,
fake_4925321266698144,
fake_7097748754191378,
fake_6195382841468382,
fake_5355711442408828

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_5596578000712868,
fake_3271649666805636,
fake_04518355437963817,
fake_4647984375588625,
fake_7895124974746408

result, different session: 
fake_5596578000712868,
fake_3271649666805636,
fake_04518355437963817,
fake_4647984375588625,
fake_7895124974746408

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_5728102125120873,
fake_030453217613123806,
fake_0826581327631366,
fake_3994253969900301,
fake_4480587027116274

result, different session: 
fake_5728102125120873,
fake_030453217613123806,
fake_0826581327631366,
fake_3994253969900301,
fake_4480587027116274

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_9835020788680271,
fake_1163480625292257,
fake_8827797465639677,
fake_1519286543361671,
fake_026764544593606

result, different session: 
fake_9835020788680271,
fake_1163480625292257,
fake_8827797465639677,
fake_1519286543361671,
fake_026764544593606

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_3349045642777462,
fake_5878844827847172,
fake_10266113302515456,
fake_8079479994800749,
fake_2136563031841281

result, different session: 
fake_3349045642777462,
fake_5878844827847172,
fake_10266113302515456,
fake_8079479994800749,
fake_2136563031841281

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_6994120378660136,
fake_5697028023198405,
fake_6857783303842042,
fake_7373174377642013,
fake_5984143280184018

result, different session: 
fake_6994120378660136,
fake_5697028023198405,
fake_6857783303842042,
fake_7373174377642013,
fake_5984143280184018

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_004906801047394271,
fake_9851034616360683,
fake_79047760295413,
fake_7482621435904155,
fake_8267817514162752

result, different session: 
fake_004906801047394271,
fake_9851034616360683,
fake_79047760295413,
fake_7482621435904155,
fake_8267817514162752

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_6161407967596413,
fake_5393951638209078,
fake_8523514422831624,
fake_762329067509611,
fake_7662299959254615

result, different session: 
fake_1777542216121557,
fake_2900455146121286,
fake_05284542810856485,
fake_6176955338095675,
fake_47769175639247186

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_7858919788622813,
fake_5780863603371917,
fake_5492538693205216,
fake_36374818038894974,
fake_7852941778512226

result, different session: 
fake_7858919788622813,
fake_5780863603371917,
fake_5492538693205216,
fake_36374818038894974,
fake_7852941778512226

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
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: 2, 2, 2, 2, 2

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 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
Failed
write: async (key) => {
      let style = document.createElement("style");
      style.type='text/css';
      let fontURI = testURI("resource", "font", key);
      style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
      document.getElementsByTagName("head")[0].appendChild(style);
      return key;
    }

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 2

result, different session: 1, 1, 1, 1, 2

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_1p

result, different session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_1p

result, different session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_1p,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_1p,
bedf8903-91f7-40b4-8861-2c4b4775a480_1p,
371b933a-76db-4bbc-9e87-1412fb103b38_1p,
ab884d29-7e62-4f69-92a5-db18d7f430a7_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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_1p

result, different session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p,
e910db86-3295-44ea-b0f2-141d7f682f05_1p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p,
e323919e-01ad-4713-a0e0-12788b8af39d_1p,
c28c0205-1252-4812-8dc8-8eea3305b475_1p

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p,
e910db86-3295-44ea-b0f2-141d7f682f05_1p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p,
e323919e-01ad-4713-a0e0-12788b8af39d_1p,
c28c0205-1252-4812-8dc8-8eea3305b475_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_1p

result, different session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_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: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_1p

result, different session: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256_1p,
ed41193b-a91d-4cd0-81ab-8a8854107c30_1p,
b43ed285-eb5d-4a40-9aa9-116344b081fa_1p,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b_1p,
b61627e3-6f32-4eaf-860d-525162a2467b_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: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

result, different session: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_1p

result, different session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_1p,
0a838421-59e6-4ce3-b6f3-42e934531656_1p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_1p,
0a860175-c009-46be-9961-2b46a37d8855_1p,
39583853-6411-4656-8308-d5458f074429_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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_1p

result, different session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_1p,
d2b09752-b8d6-44ec-8c87-08334be85367_1p,
d5c24430-61df-4b85-a66a-f778ad3a0627_1p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_1p,
a464a713-5a56-465a-8267-ca5ad5d3026e_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: 
125432da-5470-4bd9-a28c-e1fe7247a5e4_1p,
3e1a9d99-b563-44cc-bd40-965f1cfe1921_1p,
bedf8903-91f7-40b4-8861-2c4b4775a480_1p,
371b933a-76db-4bbc-9e87-1412fb103b38_1p,
ab884d29-7e62-4f69-92a5-db18d7f430a7_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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_1p

result, different session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_1p,
878d6152-cf5f-4045-a81a-61fca23589b1_1p,
1a8c0f62-e575-49aa-82fa-2368af206f33_1p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_1p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p,
e910db86-3295-44ea-b0f2-141d7f682f05_1p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p,
e323919e-01ad-4713-a0e0-12788b8af39d_1p,
c28c0205-1252-4812-8dc8-8eea3305b475_1p

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_1p,
e910db86-3295-44ea-b0f2-141d7f682f05_1p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_1p,
e323919e-01ad-4713-a0e0-12788b8af39d_1p,
c28c0205-1252-4812-8dc8-8eea3305b475_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_1p

result, different session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_1p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_1p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_1p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_1p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_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: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_1p

result, different session: 
39f3f39d-d02f-4680-b741-1d671b6882b0_1p,
d8848dcb-7e19-4775-91d7-9c6c13e052ba_1p,
8c64b5d6-88a1-4cf7-9a46-7870c8b1ff68_1p,
67ea507f-14e7-4a39-bbe0-c353019d4b23_1p,
ce970a34-89ee-4cec-bee1-9fd5fb8a661f_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: 
3e64ad26-ab88-4553-aa54-2d649cd1c256_1p,
ed41193b-a91d-4cd0-81ab-8a8854107c30_1p,
b43ed285-eb5d-4a40-9aa9-116344b081fa_1p,
6501b5b9-2c2b-4bce-afba-5f4e64c8ff8b_1p,
b61627e3-6f32-4eaf-860d-525162a2467b_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: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

result, different session: 
2e858d0b-2216-4032-82b9-582d55d00118_1p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_1p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_1p,
683773c8-9430-4736-aec3-80fc0b910969_1p,
f5e61287-ae53-4839-9876-c35d92b94f02_1p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

result, different session: 
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
XMLHttpRequest cache
Similar to the newer Fetch API, any resource received may be cached by the browser. The cache is potentially vulnerable to cross-site tracking attack.
              
Failed
write: async (key) => {
      const req = new XMLHttpRequest();
      const loadPromise = new Promise(resolve => req.addEventListener("load", resolve));
      req.open("GET", testURI("resource", "xhr", key));
      req.send();
      await loadPromise;
      return key;
    }

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
Cross-session third-party tracking testsWhich browsers prevent third-party trackers from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow third-party trackers to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
        
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
              
Failed
write: async () => {
      // Clear Alt-Svc caching first.
      let responseText = "";
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/clear");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after clear:", responseText);
      // Store "h3" state in Alt-Svc cache
      for (let i = 0; i < 3; ++i) {
        await fetch(altSvcOrigin + "/set");
        await sleepMs(100);
      }
      responseText = await fetchText(altSvcOrigin + "/protocol");
      console.log("after set:", responseText);
    }

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

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

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

unsupported: false, false, false, false, false

passed: false, false, false, true, 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, h3

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

unsupported: false, false, false, false, false

passed: false, false, false, true, false

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, h2, h3

unsupported: false, false, false, false, false

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

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

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

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

result, different session: 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
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: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_3p,
0a838421-59e6-4ce3-b6f3-42e934531656_3p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_3p,
0a860175-c009-46be-9961-2b46a37d8855_3p,
39583853-6411-4656-8308-d5458f074429_3p

result, different session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_3p,
0a838421-59e6-4ce3-b6f3-42e934531656_3p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_3p,
0a860175-c009-46be-9961-2b46a37d8855_3p,
39583853-6411-4656-8308-d5458f074429_3p

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: 
18c363dd-0a25-4118-829e-68797f7cfc6a_3p,
d2b09752-b8d6-44ec-8c87-08334be85367_3p,
d5c24430-61df-4b85-a66a-f778ad3a0627_3p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_3p,
a464a713-5a56-465a-8267-ca5ad5d3026e_3p

result, different session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_3p,
d2b09752-b8d6-44ec-8c87-08334be85367_3p,
d5c24430-61df-4b85-a66a-f778ad3a0627_3p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_3p,
a464a713-5a56-465a-8267-ca5ad5d3026e_3p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

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

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

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_3p,
878d6152-cf5f-4045-a81a-61fca23589b1_3p,
1a8c0f62-e575-49aa-82fa-2368af206f33_3p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_3p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_3p

result, different session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_3p,
878d6152-cf5f-4045-a81a-61fca23589b1_3p,
1a8c0f62-e575-49aa-82fa-2368af206f33_3p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_3p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_3p

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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_3p,
e910db86-3295-44ea-b0f2-141d7f682f05_3p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_3p,
e323919e-01ad-4713-a0e0-12788b8af39d_3p,
c28c0205-1252-4812-8dc8-8eea3305b475_3p

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_3p,
e910db86-3295-44ea-b0f2-141d7f682f05_3p,
47ca2b25-08e4-4e73-8292-842ad34ea27f_3p,
e323919e-01ad-4713-a0e0-12788b8af39d_3p,
c28c0205-1252-4812-8dc8-8eea3305b475_3p

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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_3p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_3p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_3p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_3p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_3p

result, different session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_3p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_3p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_3p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_3p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_3p

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: 
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p

result, different session: 
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p,
47a37c68-eb39-4765-8686-ffe721bfeb14_3p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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: 
2e858d0b-2216-4032-82b9-582d55d00118_3p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_3p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_3p,
683773c8-9430-4736-aec3-80fc0b910969_3p,
f5e61287-ae53-4839-9876-c35d92b94f02_3p

result, different session: 
2e858d0b-2216-4032-82b9-582d55d00118_3p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_3p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_3p,
683773c8-9430-4736-aec3-80fc0b910969_3p,
f5e61287-ae53-4839-9876-c35d92b94f02_3p

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_3p_http,
0a838421-59e6-4ce3-b6f3-42e934531656_3p_http,
823d78e7-647a-4fcc-b57a-f41d088c0b37_3p_http,
0a860175-c009-46be-9961-2b46a37d8855_3p_http,
39583853-6411-4656-8308-d5458f074429_3p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_3p_http,
d2b09752-b8d6-44ec-8c87-08334be85367_3p_http,
d5c24430-61df-4b85-a66a-f778ad3a0627_3p_http,
a54c15ec-a80d-4bef-852c-fd3333e3e985_3p_http,
a464a713-5a56-465a-8267-ca5ad5d3026e_3p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_3p_http,
878d6152-cf5f-4045-a81a-61fca23589b1_3p_http,
1a8c0f62-e575-49aa-82fa-2368af206f33_3p_http,
a48844cb-5790-4cad-985f-2ac5903cf4ba_3p_http,
e8362b3c-457f-433a-a634-b3976f2bd2e4_3p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_3p_http,
e910db86-3295-44ea-b0f2-141d7f682f05_3p_http,
47ca2b25-08e4-4e73-8292-842ad34ea27f_3p_http,
e323919e-01ad-4713-a0e0-12788b8af39d_3p_http,
c28c0205-1252-4812-8dc8-8eea3305b475_3p_http

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_3p_http,
e910db86-3295-44ea-b0f2-141d7f682f05_3p_http,
47ca2b25-08e4-4e73-8292-842ad34ea27f_3p_http,
e323919e-01ad-4713-a0e0-12788b8af39d_3p_http,
c28c0205-1252-4812-8dc8-8eea3305b475_3p_http

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_3p_http,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_3p_http,
3bbb2028-30ca-4b99-85f6-629bc53932d8_3p_http,
076272c4-4fc2-4104-b0e2-ce78add4bf49_3p_http,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_3p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same session: 
2e858d0b-2216-4032-82b9-582d55d00118_3p_http,
f3ce28e1-94bf-4b32-8a67-199a702faac3_3p_http,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_3p_http,
683773c8-9430-4736-aec3-80fc0b910969_3p_http,
f5e61287-ae53-4839-9876-c35d92b94f02_3p_http

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_3p_js,
0a838421-59e6-4ce3-b6f3-42e934531656_3p_js,
823d78e7-647a-4fcc-b57a-f41d088c0b37_3p_js,
0a860175-c009-46be-9961-2b46a37d8855_3p_js,
39583853-6411-4656-8308-d5458f074429_3p_js

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_3p_js,
d2b09752-b8d6-44ec-8c87-08334be85367_3p_js,
d5c24430-61df-4b85-a66a-f778ad3a0627_3p_js,
a54c15ec-a80d-4bef-852c-fd3333e3e985_3p_js,
a464a713-5a56-465a-8267-ca5ad5d3026e_3p_js

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_3p_js,
878d6152-cf5f-4045-a81a-61fca23589b1_3p_js,
1a8c0f62-e575-49aa-82fa-2368af206f33_3p_js,
a48844cb-5790-4cad-985f-2ac5903cf4ba_3p_js,
e8362b3c-457f-433a-a634-b3976f2bd2e4_3p_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: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_3p_js,
e910db86-3295-44ea-b0f2-141d7f682f05_3p_js,
47ca2b25-08e4-4e73-8292-842ad34ea27f_3p_js,
e323919e-01ad-4713-a0e0-12788b8af39d_3p_js,
c28c0205-1252-4812-8dc8-8eea3305b475_3p_js

result, different session: 
b6bd7e2b-fbda-44ca-b27d-7905fbb4ddb6_3p_js,
e910db86-3295-44ea-b0f2-141d7f682f05_3p_js,
47ca2b25-08e4-4e73-8292-842ad34ea27f_3p_js,
e323919e-01ad-4713-a0e0-12788b8af39d_3p_js,
c28c0205-1252-4812-8dc8-8eea3305b475_3p_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: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_3p_js,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_3p_js,
3bbb2028-30ca-4b99-85f6-629bc53932d8_3p_js,
076272c4-4fc2-4104-b0e2-ce78add4bf49_3p_js,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_3p_js

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

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

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

result, same session: , , , , 

result, different session: , , , , 

unsupported: true, true, true, true, true

passed: undefined

test failed: false, false, false, false, false
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: 
2e858d0b-2216-4032-82b9-582d55d00118_3p_js,
f3ce28e1-94bf-4b32-8a67-199a702faac3_3p_js,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_3p_js,
683773c8-9430-4736-aec3-80fc0b910969_3p_js,
f5e61287-ae53-4839-9876-c35d92b94f02_3p_js

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
85b9c2dc-4a3c-44ae-bb14-17c759676afe_3p,
0a838421-59e6-4ce3-b6f3-42e934531656_3p,
823d78e7-647a-4fcc-b57a-f41d088c0b37_3p,
0a860175-c009-46be-9961-2b46a37d8855_3p,
39583853-6411-4656-8308-d5458f074429_3p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 
18c363dd-0a25-4118-829e-68797f7cfc6a_3p,
d2b09752-b8d6-44ec-8c87-08334be85367_3p,
d5c24430-61df-4b85-a66a-f778ad3a0627_3p,
a54c15ec-a80d-4bef-852c-fd3333e3e985_3p,
a464a713-5a56-465a-8267-ca5ad5d3026e_3p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

result, same session: 
a386e0c1-6f89-4aea-8a13-12def4c0c9c3_3p,
878d6152-cf5f-4045-a81a-61fca23589b1_3p,
1a8c0f62-e575-49aa-82fa-2368af206f33_3p,
a48844cb-5790-4cad-985f-2ac5903cf4ba_3p,
e8362b3c-457f-433a-a634-b3976f2bd2e4_3p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

result, same session: 
2e9cedda-c768-4af8-ae44-7cf9a6cd99ed_3p,
f5c96863-c6e7-4c92-9c0c-e6f5877f1d5b_3p,
3bbb2028-30ca-4b99-85f6-629bc53932d8_3p,
076272c4-4fc2-4104-b0e2-ce78add4bf49_3p,
56c106e2-16d0-436c-84de-6c9b6acfb3ef_3p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

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

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

result, same session: 
2e858d0b-2216-4032-82b9-582d55d00118_3p,
f3ce28e1-94bf-4b32-8a67-199a702faac3_3p,
f7e83b2d-cbcf-4099-bf46-0172410c0a0a_3p,
683773c8-9430-4736-aec3-80fc0b910969_3p,
f5e61287-ae53-4839-9876-c35d92b94f02_3p

result, different session: , , , , 

unsupported: false, false, false, false, false

passed: true, true, true, true, true

test failed: false, false, false, false, false
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites.
              
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_7779036276956086,
fake_0984077471635636,
fake_8450199796193485,
fake_6839776082740363,
fake_6372473003732719

result, different session: 
fake_7779036276956086,
fake_0984077471635636,
fake_8450199796193485,
fake_6839776082740363,
fake_6372473003732719

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_6345367072640651,
fake_6556328479204949,
fake_07375664571419538,
fake_5868772970547707,
fake_4073327662394899

result, different session: 
fake_6345367072640651,
fake_6556328479204949,
fake_07375664571419538,
fake_5868772970547707,
fake_4073327662394899

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_5380893111348586,
fake_9278739760894603,
fake_3560398050375959,
fake_4752854298693956,
fake_0739454626073699

result, different session: 
fake_5380893111348586,
fake_9278739760894603,
fake_3560398050375959,
fake_4752854298693956,
fake_0739454626073699

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_6269721511141437,
fake_3232493089608217,
fake_8725409632198704,
fake_4807823395640911,
fake_6268394492158162

result, different session: 
fake_6269721511141437,
fake_3232493089608217,
fake_8725409632198704,
fake_4807823395640911,
fake_6268394492158162

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_6674894383082506,
fake_8530605517212253,
fake_4795990844577933,
fake_8645044790924239,
fake_2647263888594382

result, different session: 
fake_6674894383082506,
fake_8530605517212253,
fake_4795990844577933,
fake_8645044790924239,
fake_2647263888594382

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_6996677574799137,
fake_8798533838364546,
fake_3789345205314232,
fake_4741118666636641,
fake_1784542186724798

result, different session: 
fake_6996677574799137,
fake_8798533838364546,
fake_3789345205314232,
fake_4741118666636641,
fake_1784542186724798

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_6993069127883618,
fake_7436332148392952,
fake_10925250678243015,
fake_5938873240452647,
fake_7126208727599455

result, different session: 
fake_6993069127883618,
fake_7436332148392952,
fake_10925250678243015,
fake_5938873240452647,
fake_7126208727599455

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_41640779039263953,
fake_923880805794185,
fake_8783753314533369,
fake_731160302133818,
fake_8761981874520051

result, different session: 
fake_297975575764438,
fake_6648936264875298,
fake_4656940613052645,
fake_8839459669170486,
fake_81178044792543

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_9898431154882836,
fake_2819814693384539,
fake_6243249172749252,
fake_18157293072904124,
fake_43943056103416

result, different session: 
fake_9898431154882836,
fake_2819814693384539,
fake_6243249172749252,
fake_18157293072904124,
fake_43943056103416

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

test failed: false, false, false, false, false
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: 2, 2, 2, 2, 2

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 2, 1, 1, 1

result, different session: 1, 2, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 2, 2, 2, 2, 2

unsupported: false, false, false, false, false

passed: true, true, true, true, true

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 1, 1, 1, 1

result, different session: 1, 1, 1, 1, 1

unsupported: false, false, false, false, false

passed: false, false, false, false, false

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

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

result, same session: 1, 2, 1, 1, 1

result, different session: 1, 2, 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