Nightly Builds

(default settings)
brave logo
brave
1.100
chrome logo
chrome
158.0
duckduckgo logo
duckduckgo
1.212
edge logo
edge
158.0
firefox logo
firefox
160.0a1
opera logo
opera
140.0
tor logo
tor
16.0a14
vivaldi logo
vivaldi
8.3
State Partitioning testsWhich browsers isolate websites to prevent them from sharing data to track you?
A common vulnerability of web browsers is that they allow tracking companies to 'tag' your browser with some data ('state') that identifies you. When third-party trackers are embedded in websites, they can see this identifying data as you browse to different websites. Fortunately, it is possible for this category of leaks to be fixed by partitioning all data stored in the browser such that no data can be shared between websites.
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
        let responseText = '';
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/clear');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after clear:', responseText);
        // Store "h3" state in Alt-Svc cache
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/set');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after set:', responseText);
      }
read: async () => {
        const protocol = await fetchText(altSvcOrigin + '/protocol');
        if ((new URL(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same first party: h3, h3, h3
result, different first party: h2, h2, h2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
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(window.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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same first party: h3, h3, h3, h3
result, different first party: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async () => {
      // Clear Alt-Svc caching first.
        let responseText = '';
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/clear');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after clear:', responseText);
        // Store "h3" state in Alt-Svc cache
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/set');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after set:', responseText);
      }
read: async () => {
        const protocol = await fetchText(altSvcOrigin + '/protocol');
        if ((new URL(window.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(window.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(window.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(window.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 {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
result, different first party:
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed,
Error: Load failed
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
result, different first party:
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
result, different first party:
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.,
Error: NetworkError when attempting to fetch resource.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: (secret) => {
        try {
          const blobURL = URL.createObjectURL(new Blob([secret]));
          fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async (secret) => {
        const response = await fetch(`${baseURI}blob?mode=read&key=${secret}`);
        const result = await response.json();
        const blobUrl = decodeURIComponent(result.blobUrl);
        const blobResponse = await fetch(blobUrl);
        return blobResponse.text();
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
result, different first party:
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch,
Error: Failed to fetch
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
BroadcastChannel
A BroadcastChannel is designed to send messages between tabs. In some browsers it can be used for cross-site communication and tracking.
Passed
write: (secret) => {
        try {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
        try {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => {
        try {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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 {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message,
Error: no BroadcastChannel message
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => {
        try {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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 {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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 {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
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 {
          const 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) => {
          const bc = new BroadcastChannel('secrets');
          bc.onmessage = (event) => {
            if (event.data !== 'request') {
              resolve(event.data);
            }
          };
          bc.postMessage('request');
          setTimeout(() => reject(new Error('no BroadcastChannel message')), 3000);
        })
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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 {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
result, different first party:
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url'),
Error: undefined is not an object (evaluating 'cacheKeys[0].url')
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url'),
Error: Cannot read properties of undefined (reading 'url')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
result, different first party:
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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 {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
result, different first party:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_http,
272bd7fb-b9de-434f-b799-28b37bfd0008_http,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_http,
9d4da305-54b8-41ae-ad16-74257c77554c_http
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e_http,
fdc2e9f3-5586-414c-b177-8519bfd93e38_http,
7211820c-8fb8-4a11-958e-a6381d16a81f_http
result, different first party:
c92c73d8-1be6-4282-aedd-e03224a6719e_http,
fdc2e9f3-5586-414c-b177-8519bfd93e38_http,
7211820c-8fb8-4a11-958e-a6381d16a81f_http
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8_http,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_http,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_http,
59861472-4ebe-4a6d-abf8-18dd53621bb1_http,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830_http,
607f6857-5ef2-4551-8573-7583c41da544_http,
7df89f73-4b25-400d-91c1-37620c91f3d0_http,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_http
result, different first party:
edc596d6-abea-4bd4-8a0a-f69054097830_http,
607f6857-5ef2-4551-8573-7583c41da544_http,
7df89f73-4b25-400d-91c1-37620c91f3d0_http,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_http,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_http,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_http,
52418b24-aec4-44ef-bc76-c31a2df82aea_http,
e4703191-67f3-4fef-9f47-7d291112febd_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_http,
16557a9d-77e9-4669-8e8b-3baa065f318d_http,
136045ff-53a3-4f13-b463-96abc637e1eb_http,
551b76fd-39ee-437d-9fc1-399802c32d92_http,
b368155e-74b3-4d0c-a908-4c63d83e07b5_http
result, different first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_http,
16557a9d-77e9-4669-8e8b-3baa065f318d_http,
136045ff-53a3-4f13-b463-96abc637e1eb_http,
551b76fd-39ee-437d-9fc1-399802c32d92_http,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844_http,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_http,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_http,
cb586ccb-af00-4cf0-ad38-a47784c38900_http,
41302e20-1bf3-48b6-ad94-a071c0843555_http
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525_http,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_http,
b444ef2d-6d5a-4166-98ab-5d8194392be2_http,
4f7d4a70-5444-419c-ba6d-d959606a4e16_http,
922670be-c546-4202-a5b2-fb69048675b6_http
result, different first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525_http,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_http,
b444ef2d-6d5a-4166-98ab-5d8194392be2_http,
4f7d4a70-5444-419c-ba6d-d959606a4e16_http,
922670be-c546-4202-a5b2-fb69048675b6_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=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_js,
272bd7fb-b9de-434f-b799-28b37bfd0008_js,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_js,
9d4da305-54b8-41ae-ad16-74257c77554c_js
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e_js,
fdc2e9f3-5586-414c-b177-8519bfd93e38_js,
7211820c-8fb8-4a11-958e-a6381d16a81f_js
result, different first party:
c92c73d8-1be6-4282-aedd-e03224a6719e_js,
fdc2e9f3-5586-414c-b177-8519bfd93e38_js,
7211820c-8fb8-4a11-958e-a6381d16a81f_js
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8_js,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_js,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_js,
59861472-4ebe-4a6d-abf8-18dd53621bb1_js,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830_js,
607f6857-5ef2-4551-8573-7583c41da544_js,
7df89f73-4b25-400d-91c1-37620c91f3d0_js,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_js
result, different first party:
edc596d6-abea-4bd4-8a0a-f69054097830_js,
607f6857-5ef2-4551-8573-7583c41da544_js,
7df89f73-4b25-400d-91c1-37620c91f3d0_js,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_js,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_js,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_js,
52418b24-aec4-44ef-bc76-c31a2df82aea_js,
e4703191-67f3-4fef-9f47-7d291112febd_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_js,
16557a9d-77e9-4669-8e8b-3baa065f318d_js,
136045ff-53a3-4f13-b463-96abc637e1eb_js,
551b76fd-39ee-437d-9fc1-399802c32d92_js,
b368155e-74b3-4d0c-a908-4c63d83e07b5_js
result, different first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_js,
16557a9d-77e9-4669-8e8b-3baa065f318d_js,
136045ff-53a3-4f13-b463-96abc637e1eb_js,
551b76fd-39ee-437d-9fc1-399802c32d92_js,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844_js,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_js,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_js,
cb586ccb-af00-4cf0-ad38-a47784c38900_js,
41302e20-1bf3-48b6-ad94-a071c0843555_js
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525_js,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_js,
b444ef2d-6d5a-4166-98ab-5d8194392be2_js,
4f7d4a70-5444-419c-ba6d-d959606a4e16_js,
922670be-c546-4202-a5b2-fb69048675b6_js
result, different first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525_js,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_js,
b444ef2d-6d5a-4166-98ab-5d8194392be2_js,
4f7d4a70-5444-419c-ba6d-d959606a4e16_js,
922670be-c546-4202-a5b2-fb69048675b6_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:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
result, different first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
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:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
result, different first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_9409595219414431,
fake_01798913849144501,
fake_991489408648313,
fake_44185649410782135
result, different first party:
fake_6206624295971233,
fake_653652945325697,
fake_2074403369456883,
fake_25633387076540526
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_8570648730192472,
fake_44596541362109066,
fake_1885105441467474
result, different first party:
fake_8570648730192472,
fake_44596541362109066,
fake_1885105441467474
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_8295055241042955,
fake_356166769348226,
fake_4360002368373246,
fake_5887314492033491,
fake_36930058767784346
result, different first party:
fake_8977987798306928,
fake_5839302409635647,
fake_638946831568135,
fake_9971788792446952,
fake_7443578304827407
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_5360774574682876,
fake_10826310307806075,
fake_00698816595438001,
fake_2802260539813999
result, different first party:
fake_5360774574682876,
fake_10826310307806075,
fake_9876594360759654,
fake_2802260539813999
unsupported: false, false, false, false
passed: false, false, true, false
test failed: false, false, false, false
Passed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_33435588974295727,
fake_679375509517856,
fake_4950581225728645,
fake_4178101083830148,
fake_8439730372988734
result, different first party:
fake_5161085993029884,
fake_08649623066041823,
fake_09697103644216898,
fake_6275477493257904,
fake_14787002066552413
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_621015419812103,
fake_16509704230435074,
fake_6003005255712326,
fake_4184397868247236,
fake_25080736414216864
result, different first party:
fake_621015419812103,
fake_9089880638454257,
fake_6003005255712326,
fake_4184397868247236,
fake_25080736414216864
unsupported: false, false, false, false, false
passed: false, true, 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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_24574565206870114,
fake_9746474131335692,
fake_8110471324283692,
fake_3259285380034298,
fake_24537718381745788
result, different first party:
fake_38185163094477304,
fake_41170013126860905,
fake_6133346534174355,
fake_15621506433439114,
fake_018364653301004452
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same first party:
fake_031407436117509624,
fake_0007003165780588017,
fake_07620356639777359,
fake_19276205651855172,
fake_34806962906084427
result, different first party:
fake_031407436117509624,
fake_570917857433195,
fake_07620356639777359,
fake_038399915903559734,
fake_34806962906084427
unsupported: false, false, false, false, false
passed: false, true, false, true, 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.
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 1, 1, 2, 1
unsupported: false, false, false, false
passed: false, false, true, false
test failed: false, false, false, false
Passed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, true, false, false, false
test failed: false, false, false, false, false
Passed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 2, 1
unsupported: false, false, false, false, false
passed: false, true, false, true, false
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:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt', { create: true });
          const stream = await fileHandle.createWritable();
          await stream.write(secret);
          await stream.close();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt');
          const file = await fileHandle.getFile();
          return file.text();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt', { create: true });
          const stream = await fileHandle.createWritable();
          await stream.write(secret);
          await stream.close();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt');
          const file = await fileHandle.getFile();
          return file.text();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt', { create: true });
          const stream = await fileHandle.createWritable();
          await stream.write(secret);
          await stream.close();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt');
          const file = await fileHandle.getFile();
          return file.text();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt', { create: true });
          const stream = await fileHandle.createWritable();
          await stream.write(secret);
          await stream.close();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt');
          const file = await fileHandle.getFile();
          return file.text();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
result, same first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
result, different first party:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt', { create: true });
          const stream = await fileHandle.createWritable();
          await stream.write(secret);
          await stream.close();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        try {
          const root = await navigator.storage.getDirectory();
          const fileHandle = await root.getFileHandle('secret.txt');
          const file = await fileHandle.getFile();
          return file.text();
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h1.privacytests2.org:8901/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, { cache: 'no-store' });
      }
read: async () => {
        const response = await fetch('https://h2.privacytests2.org:8902/?mode=read', { cache: 'no-store' });
        return await response.text();
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id');
        return await response.text();
      }
result, same first party:
b89273bf130a9b4e9471f15a49be1a44,
95579019593447cdc5b0917c904e11b0,
b672ae1288a9621c53204bc1016196b8,
ee80593cd965bfaf5bcc54fae4f25edc
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
        for (let i = 0; i < 3; ++i) {
          await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
          await sleepMs(500);
        }
        // Are we now connecting over h3?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id');
        return await response.text();
      }
result, same first party:
0d37fa3eb73e02d5bad1a508610d0908,
bbe783201689709847641642482fa7d0,
e476c5552908a56e0d1a58d2a5887012
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: 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?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const 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?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id');
        return await response.text();
      }
result, same first party:
aa1dabbbdfcfd0b50d5c1b9dc71e58e4,
198d3c383a7997d4da05ecd9d220c660,
c884a7f87aef0cd415a6ea1b19374a3f,
5fde6287e18bcaa10e2331d1f3659752
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
      // Ensure that we can switch over to h3 via alt-svc:
        for (let i = 0; i < 3; ++i) {
          await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
          await sleepMs(500);
        }
        // Are we now connecting over h3?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id');
        return await response.text();
      }
result, same first party:
54b5594a582e6e4511238d7bb1aedb18,
f892c7c999cb935ab81ce9e5a63a062a,
4fc80b1478d1a82d07f1f2fe3605912d,
dd370d77c0efb30a139a6b3cc21e7c0c,
0f01d52909f9fe4272e2238fd4896eb4
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?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id');
        return await response.text();
      }
result, same first party:
aa2e34b5209ada257c79c9bd9c003468,
4c9672ed319fcc10429a14a98634f069,
5dc47a8de10780324f21fe28cb738436,
098b06873f0423ae783ea7094153cb3f,
aa4c3fd814a172cad410450ba1a64816
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?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const 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?
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id', { cache: 'no-store' });
        const text = await response.text();
        // Empty response text indicates we are not connecting over h3:
        if (text.trim() === '') {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const response = await fetch('https://h3.privacytests2.org:4434/connection_id');
        return await response.text();
      }
result, same first party:
2fbed8f7aac2753587532890bf5c4465,
14446e3c8c168151f401b62bd4ccb8ae,
1072fed0a9802ffe6982f696b7886668,
cbb29c98380b6581d5aa5460da67870f,
75dbab0df1dad295bb6d72905210dea4
result, different first party: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
HSTS cache

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

            
Passed
write: null
read: null
result, same first party: , , ,
result, different first party:
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected
unsupported: , , ,
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: null
read: null
result, same first party: , ,
result, different first party:
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected
unsupported: , ,
passed: true, true, true
test failed: false, false, false
Failed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, 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: null
read: null
result, same first party: , , not tested, not tested
result, different first party:
HTTPS used by default; no HSTS cache issue expected,
HTTPS used by default; no HSTS cache issue expected,
Upgraded to https,
Upgraded to https
unsupported: , , false, false
passed: true, true, false, false
test failed: false, false, false, false
Passed
write: set HSTS flag
read: read HSTS flag
result, same first party: not tested, not tested, not tested, not tested, not tested
result, different first party: Used http, Used http, Used http, Used http, Used http
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 1, 1, 2, 1
unsupported: false, false, false, false
passed: false, false, true, false
test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, true, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 2, 1
unsupported: false, false, false, false, false
passed: false, true, false, true, 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.
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:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party: undefined
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party: undefined
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
result, different first party:
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
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) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        if (navigator.locks) {
          navigator.locks.request(key, lock => new Promise((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
        if (navigator.locks) {
          navigator.locks.request(key, lock => new Promise((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name'),
Error: Cannot read properties of undefined (reading 'name')
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        if (navigator.locks) {
          navigator.locks.request(key, lock => new Promise((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
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((resolve) => {}));
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].clientId;
        } else {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (navigator.locks) {
          const queryResult = await navigator.locks.query();
          return queryResult.held[0].name;
        }
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party: 1, 1, 1
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Unsupported
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party: 1, 1, 1, 1
result, different first party: 1, 1, 2, 1
unsupported: false, false, false, false
passed: false, false, true, false
test failed: false, false, false, false
Passed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, true, false, false, false
test failed: false, false, false, false, false
Unsupported
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
result, different first party:
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received,
Error: No requests received
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 2, 1
unsupported: false, false, false, false, false
passed: false, true, false, true, 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.
Passed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1
result, different first party: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 1, 1, 2, 1
unsupported: false, false, false, false
passed: false, false, true, false
test failed: false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 1, 1
unsupported: false, false, false, false, false
passed: false, true, false, false, false
test failed: false, false, false, false, false
Passed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 2, 2, 2, 2, 2
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same first party: 1, 1, 1, 1, 1
result, different first party: 1, 2, 1, 2, 1
unsupported: false, false, false, false, false
passed: false, true, false, true, false
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 {
          const worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: none, none, none, none
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        try {
          const worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party: none, none, none
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (secret) => {
        try {
          const worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
result, different first party: none, none, none, none, none
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 worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party: none, none, none, none
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (secret) => {
        try {
          const worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
result, different first party: none, none, none, none, none
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 worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
result, different first party: none, none, none, none, none
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 worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
result, different first party:
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.,
Error: SharedWorker constructor: StorageAccess denied.
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async (secret) => {
        try {
          const worker = new window.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 () => {
        const worker = new window.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 ((new URL(window.location)).searchParams.get('thirdparty') === 'same' && message === 'none') {
          throw new Error('Unsupported');
        }
        return message;
      }
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
result, different first party: none, none, none, none, none
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 () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
4591a53932590902316f52ea0afff3993fc7d1da438d4ff21afe6236a23ad094,
f11c55974c8e401633e005f8c96b9156722a3f817669f87cf807acc0d95af54a,
4ab464de9aab1824a8230e0d90fc7bcfefbcdc0d24ade595604dffea9c844477,
ed8e591fe28b1051fbad0eec61af80584539e6b2f662cedc7da0434fc1b741c8
result, different first party:
d4a2fa1468a8b294635ef31c4c30d2da070ca2c9335d8cba14fc59302b82b136,
e5f0741a945cfa7316957661f7a89d906a7a295b1bc2068dd10458061dcc5a6c,
941962c8b36f90f64c244a06afba39f80eaa6a096598a574025d4ccd09814fab,
5345471d86486d5e2ba107dfc90298b879dd2b128917accb9c948f879b175899
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
f901efc46208d998bf928d860d603bc9c633966789c876f9a095a4ff7f871c29,
13d9c9892c437541fb40a8d5ffdc19aeccdb774f36a5f742ec9b36deab7313b7,
51382a5e2edcdf0ffbc4f0f99111198ee50af1768940bbe52f37d6fedff1e5c9
result, different first party:
dba5fa4962295333598a861487203899252b44562b83bbb80811d36482e882c2,
60cb6d65adec7ccab0c4d7a3fbdb98a3623eee11ad4adc1c536eac2d23757489,
c6bc14a3ea7fbecbda64642d58e85825ca03645fbe9a0326966cb2e2c4ac74af
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
7946b2e0bdb1c7a3c8d1d6480daab8f1a696d09ba7b543da8466fd962213f01f,
d48631c40febea6a08b053d91af35a88c39cf31da5cb8aeca4bd8549b0f8d332,
833af2d3ac278ad946d10bc69454c445bb58bf41af683ed0feb4f59f172fc4bd,
9a51d4aaa3e5f262443266049ee6e81db465669dcb1a835db4ff6aa38a31e167,
cc2a530ee762b68e69069e5b466372ee3edbbc07d5814ba61520a7430121872e
result, different first party:
4226e7fe87b4e0f70762f0012987cf0723a9eb46468dce8b27ac089d12163dd0,
23e45506fa66a9d5a9d148df43a3e3c460a8ed5ab1e73705185b6ccffe4207d6,
3b95f5ab9ebd07c37a5a1a61d32ee086640973b02b616de3d34bff4420c2947f,
60285ea671addb591914b4d6d453a8280a0d3dde0593cda948279adddfca5c50,
c3ccbdee9335a5ae7d4bd3ab40ef2ae8d60593c8479712c97ed107b48a22faf8
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
74fb92d4fdc878920c2b328d5034a6ab4fc92749fc741056b9caea6f7290a429,
5942e877cacab659d029c06f7be14909068a787e707bd0895373c4fc680021cf,
ba80cfcbeff5cfd91d8bd1ee4c9dbeab3ce0326c43db8b71dd48e93e69f06135,
ba3da69306990e68d4e5f845524b19e152a5835ec649a9b742105d5a1dd1f383
result, different first party:
f23cbddaaae7ca63a34306dd9ab9a1e4cc59042f520467e95c6035901a4cb57d,
2610ae1d0a0e36de539f9ffe64be2a75cccada925f9dbe93560774ab37f0f6a5,
1811e125ca68a8e3d727c1aa5fe9179f33830e978bec1fe222f77cd4981ac69d,
42329f26046ccb3b794fba7861d50e81f42e328fde7c4935aedde57b6340348a
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
bfd576394f75fcdf8521c12cd587d9af9e2d405e5540092a96521d600f56d2b9,
b9ac6b5e4831136fbb4503d4f9156bd6284b18a3823afc1a91f2fdd8b52d37d4,
4360729cd8f2ff06fd63e7433141bc5316dc4f39588c9f9b3324779fc3da2f38,
4929b6511c2e7a1cffac8427f51ca4101d7673521cfcd6fc2115103dc91af119,
b1017df62f0ab2be2ecbdd8b51b0af158b9d0298be51024d0c1c16da82f92311
result, different first party:
f17b7e649f649bbb8f74fe944c6dc007d792b9ace92e38034a24fb1b35a379d3,
ab6b5e1a9ebe05dbe652182e928eb25f2aad8438ea836bd1b30e1b78ee0c8da8,
c185f917a68e79747ea4d20f9ca4f1d87007a630fc0b333756f1a2a89870b2cc,
ebf87ed6d8f0f3214ce600cb9b60eace962ee5fdc2796d986762a1df9d9ae938,
01ea661f086ffaf32cbd515e3d3084469a2406355798cd658e93c05c38f94e5d
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
d4357192b93fa7c8c24b12babe7d6f240e619b240cd3c6f4996f92c85189a663,
3e9cb13b002f6b916c7803ea837598f65d298285799859b16ac2bad5eff9d52d,
a4b8c886fa578856062bef4df900cab7ebf1a845fa71dfb67828c5128e7934e1,
44df125e472e6c2db3862a8c55691472022109b4d07d2fda816e5a8411ed5c58,
12919989753034c2a58bd3a8a07d7f9a00f80eb01b2359a39cdd174ce894b0bf
result, different first party:
fb935ed1b817d4673786d327c04be555b7ccabbab74f7726a51434a7a000e772,
9e0438281d23a9553299ab5d78efdd045c4c50d06beec598a3c5a3881898b0b5,
4ef6cc0c80dec0a0821120cd198e93b09b59f8e74ab0c8df4b4fa206509be386,
aab5c62328f216cad30a0009a4bb692357e369db75eb912198e378c3ce9ec578,
6bb76720024cfe46205af7e4b89662ee513355431ecf99107f31978ec2135002
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
034a5ad0313bf19abab9ef56c28c0d9f17a737e816a77d5529a31f8b3eb6a445,
ffc635485c5161f31ac2397340da832b4f68419623ece1bbc0d731b2489296e9,
d2e37b4fd985c226ecfefe6815a6cc28071860a456c301d0444cb9567ba7c035,
f28f2695588ef0e540f05da791c6131231cbeed12d23d09c2812f97b7a9350a8,
b897f51b22ad0419dfb2eace8314fbbafcbdbaecb813ae6322027dc048ab3e61
result, different first party:
0b82678b4990913e191374e27df4cba814e7e9b9af831e271c5b9f0bc297aa68,
d52ea4f1931cba9dec3d7a03036a6ead13790f862ba161f9ae7774a09025315f,
448ee5cc04a00c7518829f2a59d3e062f5bb3b00148c1721f13c2fe83d794765,
1f310e2bf95baa2ba633831bd79bd197843f15bb411460cf716cc5b38c0c4eac,
424c2d484b913af39d11cbd05eba45a18c9deeb908061ec6d3ecdae505953dfa
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Passed
write: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
read: async () => {
        const results = await fetch('https://tls.privacytests2.org:8900/');
        return (await results.json()).sessionId;
      }
result, same first party:
0e658052b186c97df8c71453f39b3fd5b0f56eb83cd5d74f87d3d59b808c3275,
1cc09a04791d81b1aa220fa745e36cb453747273c7fc0745b22f7f180399245b,
5369dfa69b939be60ae59462a36a30acdba7a4398d5006d97d2599dc8c41f61d,
38e28cbd26489ea36b050d47ceb3a7f2e00ea728b9068005a390de31741b3fdd,
91941278948c37d1a97557b14769f4955d0e90ac8823bfd093c2455f18d7a1b6
result, different first party:
bfbd945c109b2e7cdebc4c1c78dec1c553dd52653eef887824785fef4a11f7e6,
d63de85514e42b195cc922dfc9e9a6c2e04d4365ca7f63c4cd85df7b2816ace2,
0ad79e8407473e60f454f280d093abc812c9dd58d37c5804cb06c5ee9991509d,
58a4eb06e8ac680bbf95304d8f2ffde68f7898109b17f065eeabb405bd2441ca,
4c0b35de854164ef8335a53870c09ae9f53d2ffcb0ec58b3fbb5c79cb28c3303
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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same first party: 1, 1, 1
result, different first party: 2, 2, 2
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same first party: 1, 1, 1, 1
result, different first party: 2, 2, 2, 2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
result, different first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { /* do nothing */ }
read: () => document.referrer
result, same first party:
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
https://test-pages.privacytests2.org/,
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) => window.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
272bd7fb-b9de-434f-b799-28b37bfd0008,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => window.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
c92c73d8-1be6-4282-aedd-e03224a6719e,
fdc2e9f3-5586-414c-b177-8519bfd93e38,
7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party: , ,
unsupported: false, false, false
passed: true, true, true
test failed: false, false, false
Passed
write: (secret) => window.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
eefd03c2-1231-4138-baa4-774d3158e5c8,
2a5056df-98d2-455f-a8a7-b45c830bc0d0,
00d14dd7-0ffd-445a-ae68-93d6c39639e8,
59861472-4ebe-4a6d-abf8-18dd53621bb1,
80ea1c6c-1ef5-448e-9859-0e10932ef44c
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.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
edc596d6-abea-4bd4-8a0a-f69054097830,
607f6857-5ef2-4551-8573-7583c41da544,
7df89f73-4b25-400d-91c1-37620c91f3d0,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Passed
write: (secret) => window.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
3c46d620-e1ba-49e0-91c2-27ad388d29f4,
52418b24-aec4-44ef-bc76-c31a2df82aea,
e4703191-67f3-4fef-9f47-7d291112febd
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.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
16557a9d-77e9-4669-8e8b-3baa065f318d,
136045ff-53a3-4f13-b463-96abc637e1eb,
551b76fd-39ee-437d-9fc1-399802c32d92,
b368155e-74b3-4d0c-a908-4c63d83e07b5
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.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
047815ce-dbd8-417c-a633-e834e3b08844,
d85ef60b-be0e-43b2-b73f-d9efcf57355f,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
cb586ccb-af00-4cf0-ad38-a47784c38900,
41302e20-1bf3-48b6-ad94-a071c0843555
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.sessionStorage.setItem('secret', secret)
read: () => window.sessionStorage.getItem('secret')
result, same first party:
bf38f82d-30bf-4fd4-a84a-5024eed10525,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
b444ef2d-6d5a-4166-98ab-5d8194392be2,
4f7d4a70-5444-419c-ba6d-d959606a4e16,
922670be-c546-4202-a5b2-fb69048675b6
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_61ac0a7a-b523-4ffb-bf70-405b3e8b5984,
name_272bd7fb-b9de-434f-b799-28b37bfd0008,
name_22e67ac7-a16d-4dc9-a9a6-3e6a061cac70,
name_9d4da305-54b8-41ae-ad16-74257c77554c
result, different first party: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => { window.name = 'name_' + secret; }
read: () => window.name
result, same first party:
name_c92c73d8-1be6-4282-aedd-e03224a6719e,
name_fdc2e9f3-5586-414c-b177-8519bfd93e38,
name_7211820c-8fb8-4a11-958e-a6381d16a81f
result, different first party:
name_c92c73d8-1be6-4282-aedd-e03224a6719e,
name_fdc2e9f3-5586-414c-b177-8519bfd93e38,
name_7211820c-8fb8-4a11-958e-a6381d16a81f
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (secret) => { window.name = 'name_' + secret; }
read: () => window.name
result, same first party:
name_eefd03c2-1231-4138-baa4-774d3158e5c8,
name_2a5056df-98d2-455f-a8a7-b45c830bc0d0,
name_00d14dd7-0ffd-445a-ae68-93d6c39639e8,
name_59861472-4ebe-4a6d-abf8-18dd53621bb1,
name_80ea1c6c-1ef5-448e-9859-0e10932ef44c
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_edc596d6-abea-4bd4-8a0a-f69054097830,
name_607f6857-5ef2-4551-8573-7583c41da544,
name_7df89f73-4b25-400d-91c1-37620c91f3d0,
name_6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
result, different first party:
name_edc596d6-abea-4bd4-8a0a-f69054097830,
name_607f6857-5ef2-4551-8573-7583c41da544,
name_7df89f73-4b25-400d-91c1-37620c91f3d0,
name_6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Passed
write: (secret) => { window.name = 'name_' + secret; }
read: () => window.name
result, same first party:
name_9d32dcf8-7361-494a-a7f8-4fb1ebf2b752,
name_c6d7250c-ba10-4b12-9cd7-e0d5f8590de9,
name_3c46d620-e1ba-49e0-91c2-27ad388d29f4,
name_52418b24-aec4-44ef-bc76-c31a2df82aea,
name_e4703191-67f3-4fef-9f47-7d291112febd
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_e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
name_16557a9d-77e9-4669-8e8b-3baa065f318d,
name_136045ff-53a3-4f13-b463-96abc637e1eb,
name_551b76fd-39ee-437d-9fc1-399802c32d92,
name_b368155e-74b3-4d0c-a908-4c63d83e07b5
result, different first party:
name_e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2,
name_16557a9d-77e9-4669-8e8b-3baa065f318d,
name_136045ff-53a3-4f13-b463-96abc637e1eb,
name_551b76fd-39ee-437d-9fc1-399802c32d92,
name_b368155e-74b3-4d0c-a908-4c63d83e07b5
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_047815ce-dbd8-417c-a633-e834e3b08844,
name_d85ef60b-be0e-43b2-b73f-d9efcf57355f,
name_c3e2e662-e121-4f1c-ab2d-a850e5bb3f10,
name_cb586ccb-af00-4cf0-ad38-a47784c38900,
name_41302e20-1bf3-48b6-ad94-a071c0843555
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_bf38f82d-30bf-4fd4-a84a-5024eed10525,
name_91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
name_b444ef2d-6d5a-4166-98ab-5d8194392be2,
name_4f7d4a70-5444-419c-ba6d-d959606a4e16,
name_922670be-c546-4202-a5b2-fb69048675b6
result, different first party:
name_bf38f82d-30bf-4fd4-a84a-5024eed10525,
name_91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7,
name_b444ef2d-6d5a-4166-98ab-5d8194392be2,
name_4f7d4a70-5444-419c-ba6d-d959606a4e16,
name_922670be-c546-4202-a5b2-fb69048675b6
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
HTTPS testsWhich browsers prevent unencrypted network connections?
HTTPS is the protocol that web browsers use to connect securely to websites. When HTTPS is being used, the connection is encrypted so that third parties on the network cannot read content being sent between the server and your browser. In the past, insecure connections were the default and websites would need to actively request that a browser use HTTPS. Now the status quo is shifting, and browser makers are moving toward a world where HTTPS is the default protocol.`
Insecure website warning

            
Passed
passed: true, true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Passed
passed: true, true, true
result:
Insecure website never loaded,
Insecure website never loaded,
Insecure website never loaded
Failed
passed: false, false, false, false, false
result:
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded,
Insecure website loaded
Failed
passed: true, true, false, false
result:
Insecure website never loaded,
Insecure website never 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
passed: true, true, true, true
Passed
upgraded: true, true, true
passed: true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Upgradable hyperlink
Checks to see if the user has clicked on a hyperlink to an insecure address, if the browser upgrades that address to HTTPS whenever possible.
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true
passed: true, true, true
Failed
upgraded: false, false, false, false, false
passed: false, false, false, false, false
Passed
upgraded: true, true, true, true
passed: true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Passed
upgraded: true, true, true, true, true
passed: true, true, true, true, true
Upgradable image
Checks to see if the browser attempts to upgrade an insecure address for an image to HTTPS whenever possible.
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true
result: upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true
result: upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, true, true
result: upgraded, upgraded, upgraded, upgraded, upgraded
Passed
passed: true, true, true, 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
result: blocked, blocked, blocked, blocked
Passed
passed: true, true, true
result: blocked, blocked, blocked
Passed
passed: true, true, true, true, true
result: blocked, blocked, blocked, blocked, blocked
Passed
passed: true, true, true, true
result: 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.
Failed
SNI_status: encrypted
passed: true, true, true, false
Passed
SNI_status: encrypted
passed: true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Passed
SNI_status: encrypted
passed: true, true, true, true, true
Failed
SNI_status: plaintext
passed: false, false, false, false, false
Passed
SNI_status: encrypted
passed: true, true, true, true, true
GPC enabled first-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a website not to sell the user's personal data to third parties. This test checks to see if the GPC header is sent by default to the top-level website.
Passed
header value: 1
passed: true, true, true, true
Failed
header value: undefined
passed: false, false, false
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Failed
header value: undefined
passed: false, false, false, false, false
Passed
header value: 1
passed: true, true, true, true, true
Failed
header value: undefined
passed: false, false, false, false, false
GPC enabled third-party
The Global Privacy Control is an HTTP header that can be sent by a browser to instruct a visited website not to sell the user's personal data to other parties. This test checks to see if the GPC header is sent to third-party elements on the web page.
Passed
sec-gpc: 1
passed: true, true, true, true
Failed
passed: false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false
Failed
passed: false, false, false, false, false
Failed
passed: false, false, false, false, false
Passed
sec-gpc: 1
passed: true, true, true, true, true
Failed
passed: false, false, false, false, false
IP address hidden
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, true, true, true
Failed
passed: true, false, true
Failed
passed: true, false, true, true, false
Failed
passed: true, false, true, false
Failed
passed: false, true, true, false, true
Failed
passed: false, true, true, false, true
Passed
passed: true, true, true, true, true
Failed
passed: false, false, false, true, false
Stream isolation
Browsers that use Tor can use a different Tor circuit per top-level website.
Unsupported
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Unsupported
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false
Unsupported
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false
Unsupported
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Unsupported
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: true, true, true, true, true
readSameFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
readDifferentFirstParty:
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported,
Error: Unsupported
testFailed: false, false, false, false, false
Passed
write: () => {
        if (!usingTor) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        if (usingTor) {
          return ipAddress;
        } else {
          throw new Error('Unsupported');
        }
      }
unsupported: false, false, false, false, false
readSameFirstParty:
2001:67c:e60:c0c:192:42:116:55,
2001:67c:289c:4::79,
185.227.134.106,
2602:f6f6:2:ad5c::1,
2a0e:97c0:3e3:460:1337:b01b:1337:2
readDifferentFirstParty:
2a0b:f4c2::22,
91.92.109.126,
2a0b:f4c2::21,
2a0b:f4c2::3,
2001:67c:e60:c0c:192:42:116:53
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
passed: false, false, false, false
Failed
IsTorExit: false, false, false
passed: false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false
passed: false, false, false, false
Failed
IsTorExit: false, false, false, false, false
passed: false, false, false, false, false
Failed
IsTorExit: false, false, false, false, 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').`,
System font detection
Web pages can detect the presence of a font installed on the user's system. The presence or absence of various fonts is commonly used to fingerprint users.
Passed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: true,true,true,true
Failed
expression: undefined
desired expression: undefined
actual value: undefined
desired value: undefined
passed: false,false,false
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
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
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
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
__hssc
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
__hstc
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
__s
Drip.com email address tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
_hsenc
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
_openstat
Yandex tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
dclid
DoubleClick Click ID (Google)
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
fbclid
Facebook Click Identifier
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
gclid
Google Click Identifier
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
hsCtaTracking
HubSpot tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
mc_eid
Mailchimp Email ID (email recipient's address)
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
mkt_tok
Adobe Marketo tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
ml_subscriber
MailerLite email tracking
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
ml_subscriber_hash
MailerLite email tracking
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
msclkid
Microsoft Click ID
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
oly_anon_id
Omeda marketing 'anonymous' customer id
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
oly_enc_id
Omeda marketing 'known' customer id
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
rb_clickid
Unknown high-entropy tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
s_cid
Adobe Site Catalyst tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
vero_conv
Vero tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
vero_id
Vero tracking parameter
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
wickedid
Wicked Reports e-commerce tracking
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false, false, false
yclid
Yandex Click ID
Passed
passed: true, true, true, true
Failed
value: 5388749818657461
passed: false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Failed
value: 5388749818657461
passed: false, false, false, false, false
Passed
passed: true, true, true, true, true
Failed
value: 5388749818657461
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
Passed
url: https://munchkin.marketo.net/munchkin.js
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Passed
url: https://munchkin.marketo.net/munchkin.js
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: , false
Passed
url: https://munchkin.marketo.net/munchkin.js
Failed
url: https://munchkin.marketo.net/munchkin.js
passed: , false, false
Passed
url: https://munchkin.marketo.net/munchkin.js
passed: true, true, true, true, true
Adobe Audience Manager
Tests whether the browser blocks the page from loading the tracker at https://dpm.demdex.net/ibs
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Failed
url: https://dpm.demdex.net/ibs
passed: false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Failed
url: https://dpm.demdex.net/ibs
passed: false
Failed
url: https://dpm.demdex.net/ibs
passed: false, false, false, false
Passed
url: https://dpm.demdex.net/ibs
passed: true, true, true, true, true
Amazon adsystem
Tests whether the browser blocks the page from loading the tracker at https://s.amazon-adsystem.com/dcm
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false
Failed
url: https://s.amazon-adsystem.com/dcm
passed: false, false, false, false, false
Passed
url: https://s.amazon-adsystem.com/dcm
Failed
url: https://s.amazon-adsystem.com/dcm
passed: , false, false
Passed
url: https://s.amazon-adsystem.com/dcm
passed: true, true, true, true, true
AppNexus
Tests whether the browser blocks the page from loading the tracker at https://ib.adnxs.com/px?id=178248&t=1
Passed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: true, true, true, true
Failed
url: https://ib.adnxs.com/px?id=178248&t=1
passed: false, false
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
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
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
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
Passed
url: 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
Passed
url: https://bat.bing.com/bat.js
Passed
url: https://bat.bing.com/bat.js
Failed
url: https://bat.bing.com/bat.js
passed: , false, false
Passed
url: https://bat.bing.com/bat.js
passed: true, true, true, true, true
Chartbeat
Tests whether the browser blocks the page from loading the tracker at https://static.chartbeat.com/js/chartbeat.js
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true
Failed
url: https://static.chartbeat.com/js/chartbeat.js
passed: false, false, false
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
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
Passed
url: https://static.chartbeat.com/js/chartbeat.js
passed: true, true, true, true, true
Criteo
Tests whether the browser blocks the page from loading the tracker at https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: , false, false
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
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
Failed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: false, false, false, true, false
Passed
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
passed: true, true, true, true, true
DoubleClick (Google)
Tests whether the browser blocks the page from loading the tracker at https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: , false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
Failed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: false, false, false
Passed
url: https://securepubads.g.doubleclick.net/static/glade.js
passed: true, true, true, true, true
Facebook tracking
Tests whether the browser blocks the page from loading the tracker at https://connect.facebook.net/en_US/fbevents.js
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false
Failed
url: https://connect.facebook.net/en_US/fbevents.js
passed: false, false, false, false, false
Passed
url: https://connect.facebook.net/en_US/fbevents.js
passed: true, true, true, true, true
Google (third-party ad pixel)
Tests whether the browser blocks the page from loading the tracker at https://www.google.com/pagead/1p-user-list/
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: , false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Passed
url: https://www.google.com/pagead/1p-user-list/
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: , false
Passed
url: https://www.google.com/pagead/1p-user-list/
Failed
url: https://www.google.com/pagead/1p-user-list/
passed: , false, false
Passed
url: https://www.google.com/pagead/1p-user-list/
passed: true, true, true, true, true
Google Analytics
Tests whether the browser blocks the page from loading the tracker at https://google-analytics.com/urchin.js
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Failed
url: https://google-analytics.com/urchin.js
passed: false, false
Failed
url: https://google-analytics.com/urchin.js
passed: , false
Failed
url: https://google-analytics.com/urchin.js
passed: false
Failed
url: https://google-analytics.com/urchin.js
passed: false, false, false
Passed
url: https://google-analytics.com/urchin.js
passed: true, true, true, true, true
Google Tag Manager
Tests whether the browser blocks the page from loading the tracker at https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: , false, false
Failed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: false, false, false, false
Passed
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
passed: true, true, true, true, true
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
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: true, true, true, true, true
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, false, false, false
Passed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
Failed
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
passed: false, false, 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
New Relic
Tests whether the browser blocks the page from loading the tracker at https://js-agent.newrelic.com/nr-1212.min.js
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: false, false
Failed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: , false, false, false
Passed
url: https://js-agent.newrelic.com/nr-1212.min.js
passed: true, true, true, true, true
Quantcast
Tests whether the browser blocks the page from loading the tracker at https://pixel.quantserve.com/pixel
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true
Failed
url: https://pixel.quantserve.com/pixel
passed: false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
Passed
url: https://pixel.quantserve.com/pixel
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Failed
url: https://pixel.quantserve.com/pixel
passed: false
Failed
url: https://pixel.quantserve.com/pixel
passed: false, false, false, false
Passed
url: https://pixel.quantserve.com/pixel
passed: true, true, true, true, true
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
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: , false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
Failed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: , false, false
Passed
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
passed: true, true, true, true, true
Taboola
Tests whether the browser blocks the page from loading the tracker at https://trc.taboola.com/futureplc-tomsguide/trc/3/json
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false
Failed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: false, false, false, false, false
Passed
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
passed: true, true, true, true, true
Twitter pixel
Tests whether the browser blocks the page from loading the tracker at https://t.co/i/adsct
Passed
url: https://t.co/i/adsct
passed: true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Failed
url: https://t.co/i/adsct
passed: false, false
Failed
url: https://t.co/i/adsct
passed: false, false, false, false, false
Passed
url: https://t.co/i/adsct
Failed
url: https://t.co/i/adsct
passed: false, false, false
Passed
url: https://t.co/i/adsct
passed: true, true, true, true, true
Yandex Ads
Tests whether the browser blocks the page from loading the tracker at https://yandex.ru/ads/system/header-bidding.js
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false
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
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Failed
url: https://yandex.ru/ads/system/header-bidding.js
passed: false, false, false, false, false
Passed
url: https://yandex.ru/ads/system/header-bidding.js
passed: true, true, true, true, true
Tracking cookie protection testsWhich browsers block important known tracking cookies?
A large fraction of web pages on the web have hidden third-party trackers that read and write cookies in your browser. These cookies can be used to track your browsing across websites. This section checks to see if a browser stops cross-site tracking by cookies from 20 of the largest trackers listed by https://whotracks.me.`,
Adobe
Tests whether the browser stops cookies from munchkin.marketo.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://munchkin.marketo.net/munchkin.js
cookieFound: 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
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://munchkin.marketo.net/munchkin.js
cookieFound: false, false, false, false, false
Adobe Audience Manager
Tests whether the browser stops cookies from dpm.demdex.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://dpm.demdex.net/ibs
cookieFound: 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
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dpm.demdex.net/ibs
cookieFound: false, false, false, false, false
Amazon adsystem
Tests whether the browser stops cookies from s.amazon-adsystem.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://s.amazon-adsystem.com/dcm
cookieFound: 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
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://s.amazon-adsystem.com/dcm
cookieFound: false, false, false, false, false
AppNexus
Tests whether the browser stops cookies from ib.adnxs.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://ib.adnxs.com/px?id=178248&t=1
cookieFound: false, false, false, false, false
Bing Ads
Tests whether the browser stops cookies from bat.bing.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://bat.bing.com/bat.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://bat.bing.com/bat.js
cookieFound: false, false, false, false, false
Chartbeat
Tests whether the browser stops cookies from static.chartbeat.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://static.chartbeat.com/js/chartbeat.js
cookieFound: false, false, false, false, false
Criteo
Tests whether the browser stops cookies from dis.criteo.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: 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
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx
cookieFound: false, false, false, false, false
DoubleClick (Google)
Tests whether the browser stops cookies from securepubads.g.doubleclick.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: 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
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://securepubads.g.doubleclick.net/static/glade.js
cookieFound: false, false, false, false, false
Facebook tracking
Tests whether the browser stops cookies from connect.facebook.net from tracking users across websites.
Passed
passed: true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: 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
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://connect.facebook.net/en_US/fbevents.js
cookieFound: false, false, false, false, false
Google (third-party ad pixel)
Tests whether the browser stops cookies from www.google.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://www.google.com/pagead/1p-user-list/
cookieFound: 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
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.google.com/pagead/1p-user-list/
cookieFound: false, false, false, false, false
Google Analytics
Tests whether the browser stops cookies from google-analytics.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://google-analytics.com/urchin.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://google-analytics.com/urchin.js
cookieFound: false, false, false, false, false
Google Tag Manager
Tests whether the browser stops cookies from www.googletagmanager.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL
cookieFound: false, false, false, false, false
Index Exchange
Tests whether the browser stops cookies from dsum-sec.casalemedia.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: 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
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1
cookieFound: false, false, false, false, false
New Relic
Tests whether the browser stops cookies from js-agent.newrelic.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://js-agent.newrelic.com/nr-1212.min.js
cookieFound: false, false, false, false, false
Quantcast
Tests whether the browser stops cookies from pixel.quantserve.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://pixel.quantserve.com/pixel
cookieFound: 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
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://pixel.quantserve.com/pixel
cookieFound: false, false, false, false, false
Scorecard Research Beacon
Tests whether the browser stops cookies from sb.scorecardresearch.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Failed
passed: false, false, false, false
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: true, true, true, true
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js
cookieFound: false, false, false, false, false
Taboola
Tests whether the browser stops cookies from trc.taboola.com from tracking users across websites.
Passed
passed: true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: 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
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json
cookieFound: false, false, false, false, false
Twitter pixel
Tests whether the browser stops cookies from t.co from tracking users across websites.
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://t.co/i/adsct
cookieFound: true, true, true
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://t.co/i/adsct
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://t.co/i/adsct
cookieFound: false, false, false, false, false
Yandex Ads
Tests whether the browser stops cookies from yandex.ru from tracking users across websites.
Passed
passed: true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Failed
passed: false, false, false
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: 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
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Failed
passed: true, true, false, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, true, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Passed
passed: true, true, true, true, true
url: https://yandex.ru/ads/system/header-bidding.js
cookieFound: false, false, false, false, false
Cross-session first-party tracking testsWhich browsers prevent websites from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow websites ("first parties") to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?)
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned.
Passed
write: async () => {
      // Clear Alt-Svc caching first.
        let responseText = '';
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/clear');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after clear:', responseText);
        // Store "h3" state in Alt-Svc cache
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/set');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after set:', responseText);
      }
read: async () => {
        const protocol = await fetchText(altSvcOrigin + '/protocol');
        if ((new URL(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h3, h3, h3, h3
result, different session: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h3, h3, h3
result, different session: h3, h3, h3
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h2, h2, h2, h2, h2
result, different session: h3, h3, h3, h3, h3
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
        let responseText = '';
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/clear');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after clear:', responseText);
        // Store "h3" state in Alt-Svc cache
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/set');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after set:', responseText);
      }
read: async () => {
        const protocol = await fetchText(altSvcOrigin + '/protocol');
        if ((new URL(window.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(window.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(window.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(window.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 {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
result, different session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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 {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
047815ce-dbd8-417c-a633-e834e3b08844_1p,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_1p,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_1p,
cb586ccb-af00-4cf0-ad38-a47784c38900_1p,
41302e20-1bf3-48b6-ad94-a071c0843555_1p
result, different session:
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined,
Error: can't access property "url",
cacheKeys[0] is undefined
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_1p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_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.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p_http,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p_http,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p_http,
9d4da305-54b8-41ae-ad16-74257c77554c_1p_http
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p_http,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p_http,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p_http
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p_http,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p_http,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p_http
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p_http,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p_http,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p_http,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p_http,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p_http
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p_http,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p_http,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p_http,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p_http,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p_http,
607f6857-5ef2-4551-8573-7583c41da544_1p_http,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p_http,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p_http
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p_http,
607f6857-5ef2-4551-8573-7583c41da544_1p_http,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p_http,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p_http,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p_http,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p_http,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p_http,
e4703191-67f3-4fef-9f47-7d291112febd_1p_http
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p_http,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p_http,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p_http,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p_http,
e4703191-67f3-4fef-9f47-7d291112febd_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p_http,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p_http,
136045ff-53a3-4f13-b463-96abc637e1eb_1p_http,
551b76fd-39ee-437d-9fc1-399802c32d92_1p_http,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p_http
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p_http,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p_http,
136045ff-53a3-4f13-b463-96abc637e1eb_1p_http,
551b76fd-39ee-437d-9fc1-399802c32d92_1p_http,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
047815ce-dbd8-417c-a633-e834e3b08844_1p_http,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_1p_http,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_1p_http,
cb586ccb-af00-4cf0-ad38-a47784c38900_1p_http,
41302e20-1bf3-48b6-ad94-a071c0843555_1p_http
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p_http,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p_http,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p_http,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p_http,
922670be-c546-4202-a5b2-fb69048675b6_1p_http
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p_http,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p_http,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p_http,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p_http,
922670be-c546-4202-a5b2-fb69048675b6_1p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p_js,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p_js,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p_js,
9d4da305-54b8-41ae-ad16-74257c77554c_1p_js
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p_js,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p_js,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p_js
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p_js,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p_js,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p_js
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p_js,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p_js,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p_js,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p_js,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p_js
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p_js,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p_js,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p_js,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p_js,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p_js,
607f6857-5ef2-4551-8573-7583c41da544_1p_js,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p_js,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p_js
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p_js,
607f6857-5ef2-4551-8573-7583c41da544_1p_js,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p_js,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p_js,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p_js,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p_js,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p_js,
e4703191-67f3-4fef-9f47-7d291112febd_1p_js
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p_js,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p_js,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p_js,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p_js,
e4703191-67f3-4fef-9f47-7d291112febd_1p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p_js,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p_js,
136045ff-53a3-4f13-b463-96abc637e1eb_1p_js,
551b76fd-39ee-437d-9fc1-399802c32d92_1p_js,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p_js
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p_js,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p_js,
136045ff-53a3-4f13-b463-96abc637e1eb_1p_js,
551b76fd-39ee-437d-9fc1-399802c32d92_1p_js,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
047815ce-dbd8-417c-a633-e834e3b08844_1p_js,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_1p_js,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_1p_js,
cb586ccb-af00-4cf0-ad38-a47784c38900_1p_js,
41302e20-1bf3-48b6-ad94-a071c0843555_1p_js
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p_js,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p_js,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p_js,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p_js,
922670be-c546-4202-a5b2-fb69048675b6_1p_js
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p_js,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p_js,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p_js,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p_js,
922670be-c546-4202-a5b2-fb69048675b6_1p_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 session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
047815ce-dbd8-417c-a633-e834e3b08844_1p,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_1p,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_1p,
cb586ccb-af00-4cf0-ad38-a47784c38900_1p,
41302e20-1bf3-48b6-ad94-a071c0843555_1p
result, different session: , , , ,
unsupported: false, false, false, false, false
passed: true, true, true, true, true
test failed: false, false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_1p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_1p
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.
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_8728398624920388,
fake_9385152021753727,
fake_9700236012456327,
fake_08502068494078419
result, different session:
fake_8728398624920388,
fake_9385152021753727,
fake_9700236012456327,
fake_08502068494078419
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_2186657163675778,
fake_4451096202896896,
fake_6593286382136185
result, different session:
fake_2186657163675778,
fake_4451096202896896,
fake_6593286382136185
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_566667890429932,
fake_13485951769289461,
fake_22415283682934461,
fake_24862492264643055,
fake_25950264876805007
result, different session:
fake_566667890429932,
fake_13485951769289461,
fake_22415283682934461,
fake_24862492264643055,
fake_25950264876805007
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_7419514362306363,
fake_9536398231685421,
fake_37006458997449365,
fake_35075543365191697
result, different session:
fake_7419514362306363,
fake_9536398231685421,
fake_37006458997449365,
fake_35075543365191697
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_04716599762421114,
fake_26262769020185717,
fake_9909833402012711,
fake_14093548547598966,
fake_7094132693660962
result, different session:
fake_04716599762421114,
fake_26262769020185717,
fake_9909833402012711,
fake_14093548547598966,
fake_7094132693660962
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_6012317893852952,
fake_9653216418630057,
fake_40547341450676844,
fake_42202493487783244,
fake_8310203685268258
result, different session:
fake_6012317893852952,
fake_9653216418630057,
fake_40547341450676844,
fake_42202493487783244,
fake_8310203685268258
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_897284000225814,
fake_016989925960362084,
fake_48440146320675903,
fake_5996494480455177,
fake_2535147462877221
result, different session:
fake_41825651085614846,
fake_05699042527107556,
fake_6575424467789803,
fake_261022742415965,
fake_8546247500594282
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_1711645929619292,
fake_8816238134750363,
fake_26896491045173865,
fake_2374730085198422,
fake_06335140082250668
result, different session:
fake_1711645929619292,
fake_8816238134750363,
fake_26896491045173865,
fake_2374730085198422,
fake_06335140082250668
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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
result, different session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_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:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_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:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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:
047815ce-dbd8-417c-a633-e834e3b08844_1p,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_1p,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_1p,
cb586ccb-af00-4cf0-ad38-a47784c38900_1p,
41302e20-1bf3-48b6-ad94-a071c0843555_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:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_1p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_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) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
result, different session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_1p,
272bd7fb-b9de-434f-b799-28b37bfd0008_1p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_1p,
9d4da305-54b8-41ae-ad16-74257c77554c_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_1p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_1p,
7211820c-8fb8-4a11-958e-a6381d16a81f_1p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_1p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_1p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_1p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_1p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_1p,
607f6857-5ef2-4551-8573-7583c41da544_1p,
7df89f73-4b25-400d-91c1-37620c91f3d0_1p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_1p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_1p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_1p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_1p,
52418b24-aec4-44ef-bc76-c31a2df82aea_1p,
e4703191-67f3-4fef-9f47-7d291112febd_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_1p,
16557a9d-77e9-4669-8e8b-3baa065f318d_1p,
136045ff-53a3-4f13-b463-96abc637e1eb_1p,
551b76fd-39ee-437d-9fc1-399802c32d92_1p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_1p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Passed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
047815ce-dbd8-417c-a633-e834e3b08844_1p,
d85ef60b-be0e-43b2-b73f-d9efcf57355f_1p,
c3e2e662-e121-4f1c-ab2d-a850e5bb3f10_1p,
cb586ccb-af00-4cf0-ad38-a47784c38900_1p,
41302e20-1bf3-48b6-ad94-a071c0843555_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) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_1p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_1p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_1p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_1p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_1p,
922670be-c546-4202-a5b2-fb69048675b6_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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Unsupported
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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.
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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h3, h3, h3, h3
result, different session: h2, h2, h2, h2
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h3, h3, h3
result, different session: h3, h3, h3
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
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(window.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(window.location)).searchParams.get('thirdparty') === 'same') {
          if (protocol !== 'h3') {
            throw new Error('Unsupported');
          }
        }
        return protocol;
      }
result, same session: h3, h3, h3, h3
result, different session: h3, h3, h3, h3
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async () => {
      // Clear Alt-Svc caching first.
        let responseText = '';
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/clear');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after clear:', responseText);
        // Store "h3" state in Alt-Svc cache
        for (let i = 0; i < 3; ++i) {
          await fetch(altSvcOrigin + '/set');
          await sleepMs(100);
        }
        responseText = await fetchText(altSvcOrigin + '/protocol');
        console.log('after set:', responseText);
      }
read: async () => {
        const protocol = await fetchText(altSvcOrigin + '/protocol');
        if ((new URL(window.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(window.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(window.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(window.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 {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
result, different session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_3p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_3p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_3p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_3p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_3p
result, different session:
eefd03c2-1231-4138-baa4-774d3158e5c8_3p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_3p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_3p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_3p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_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 {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
result, different session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: async (key) => {
        try {
          const cache = await window.caches.open('supercookies');
          cache.addAll([`test.css?key=${key}`]);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: async () => {
        const cache = await window.caches.open('supercookies');
        const cacheKeys = await cache.keys();
        const url = cacheKeys[0].url;
        return (new URL(url)).searchParams.get('key');
      }
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_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.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p_http,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p_http,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p_http,
9d4da305-54b8-41ae-ad16-74257c77554c_3p_http
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p_http,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p_http,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p_http
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p_http,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p_http,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p_http
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Unsupported
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p_http,
607f6857-5ef2-4551-8573-7583c41da544_3p_http,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p_http,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p_http
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p_http,
607f6857-5ef2-4551-8573-7583c41da544_3p_http,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p_http,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p_http
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p_http,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p_http,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p_http,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p_http,
e4703191-67f3-4fef-9f47-7d291112febd_3p_http
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p_http,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p_http,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p_http,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p_http,
e4703191-67f3-4fef-9f47-7d291112febd_3p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p_http,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p_http,
136045ff-53a3-4f13-b463-96abc637e1eb_3p_http,
551b76fd-39ee-437d-9fc1-399802c32d92_3p_http,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p_http
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p_http,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p_http,
136045ff-53a3-4f13-b463-96abc637e1eb_3p_http,
551b76fd-39ee-437d-9fc1-399802c32d92_3p_http,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
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.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: async (secret) => {
      // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value.
        await fetch(`${baseURI}cookie?secret=${secret}_http`);
      }
read: async () => {
      // Test if we now send a requests with a 'cookie' header containing the secret.
        const response = await fetch(`${baseURI}headers`);
        const cookie = (await response.json()).cookie;
        return cookie ? cookie.match(/secret=([\w-]+)/)[1] : null;
      }
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p_http,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p_http,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p_http,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p_http,
922670be-c546-4202-a5b2-fb69048675b6_3p_http
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p_http,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p_http,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p_http,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p_http,
922670be-c546-4202-a5b2-fb69048675b6_3p_http
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them.
Passed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p_js,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p_js,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p_js,
9d4da305-54b8-41ae-ad16-74257c77554c_3p_js
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p_js,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p_js,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p_js
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p_js,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p_js,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p_js
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Unsupported
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p_js,
607f6857-5ef2-4551-8573-7583c41da544_3p_js,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p_js,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p_js
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p_js,
607f6857-5ef2-4551-8573-7583c41da544_3p_js,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p_js,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p_js
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p_js,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p_js,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p_js,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p_js,
e4703191-67f3-4fef-9f47-7d291112febd_3p_js
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p_js,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p_js,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p_js,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p_js,
e4703191-67f3-4fef-9f47-7d291112febd_3p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p_js,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p_js,
136045ff-53a3-4f13-b463-96abc637e1eb_3p_js,
551b76fd-39ee-437d-9fc1-399802c32d92_3p_js,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p_js
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p_js,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p_js,
136045ff-53a3-4f13-b463-96abc637e1eb_3p_js,
551b76fd-39ee-437d-9fc1-399802c32d92_3p_js,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p_js
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (secret) => {
        document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`;
      }
read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p_js,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p_js,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p_js,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p_js,
922670be-c546-4202-a5b2-fb69048675b6_3p_js
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p_js,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p_js,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p_js,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p_js,
922670be-c546-4202-a5b2-fb69048675b6_3p_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 session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
result, different session: , , ,
unsupported: false, false, false, false
passed: true, true, true, true
test failed: false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Unsupported
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
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 session: , , , ,
result, different session: , , , ,
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (data) => {
        const msPerHour = 60 * 60 * 1000;
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        window.cookieStore.set({
          name: 'partition_test',
          value: data,
          expires: Date.now() + msPerHour,
          sameSite: 'none'
        });
      }
read: async () => {
        if (!window.cookieStore) {
          throw new Error('Unsupported');
        }
        const cookie = await window.cookieStore.get('partition_test');
        if (!cookie) {
          return null;
        }
        return cookie.value;
      }
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
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.
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_6188555935841777,
fake_1253746656122885,
fake_48904218097650687,
fake_8476618336458737
result, different session:
fake_6188555935841777,
fake_1253746656122885,
fake_48904218097650687,
fake_8476618336458737
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_6739375726149119,
fake_5249375580624493,
fake_2907566162094657
result, different session:
fake_6739375726149119,
fake_5249375580624493,
fake_2907566162094657
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_6487409917441156,
fake_6425494928618991,
fake_8918035165897173,
fake_6371289635832331,
fake_5507081540960737
result, different session:
fake_6487409917441156,
fake_6425494928618991,
fake_8918035165897173,
fake_6371289635832331,
fake_5507081540960737
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_10633656703047256,
fake_7754057735114726,
fake_49319106754165776,
fake_13851437707707093
result, different session:
fake_10633656703047256,
fake_7754057735114726,
fake_49319106754165776,
fake_13851437707707093
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_6556162720656342,
fake_7747982662194144,
fake_3460455703703096,
fake_8112566930340035,
fake_31737097731292785
result, different session:
fake_6556162720656342,
fake_7747982662194144,
fake_3460455703703096,
fake_8112566930340035,
fake_31737097731292785
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_9224162381094052,
fake_5154133386476012,
fake_14836121585743278,
fake_21651202819640525,
fake_28030471509112775
result, different session:
fake_9224162381094052,
fake_5154133386476012,
fake_14836121585743278,
fake_21651202819640525,
fake_28030471509112775
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_2609929405488236,
fake_2819486386672312,
fake_29024393187864206,
fake_6744369536142325,
fake_7342056477662284
result, different session:
fake_0770274571747207,
fake_6394467496273535,
fake_06765032627950252,
fake_8433015101680557,
fake_8976855932189658
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="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return key;
      }
read: async (key) => {
        const href = testURI('resource', 'css', key);
        const head = document.getElementsByTagName('head')[0];
        head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`;
        const testElement = document.querySelector('#css');
        let fontFamily;
        while (true) {
          await sleepMs(100);
          fontFamily = window.getComputedStyle(testElement).fontFamily;
          if (fontFamily.startsWith('fake')) {
            break;
          }
        }
        console.log(fontFamily);
        return fontFamily;
      }
result, same session:
fake_20460606106629786,
fake_543218414906103,
fake_5609546459438763,
fake_002157188303234525,
fake_2412653132953686
result, different session:
fake_20460606106629786,
fake_543218414906103,
fake_5609546459438763,
fake_002157188303234525,
fake_2412653132953686
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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => key
read: async (key) => {
      // Wait for the favicon to load (defined in supercookies.html)
        await sleepMs(2000);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const 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);
        const response = await fetch(
          testURI('ctr', 'favicon', key), { cache: 'reload' });
        const count = (await response.text()).trim();
        if (count === '0') {
          throw new Error('No requests received');
        }
        return count;
      }
result, same session: 3, 3, 3, 3, 3
result, different session: 3, 3, 3, 3, 3
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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const countResponse = await fetch(testURI('ctr', 'fetch', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        return key;
      }
read: async (key) => {
        await fetch(testURI('resource', 'fetch', key),
          { cache: 'force-cache' });
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const response = await fetch(
          testURI('ctr', 'font', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`;
        document.getElementsByTagName('head')[0].appendChild(style);
        return key;
      }
read: async (key) => {
        const text = document.createElement('span');
        text.id = 'text';
        text.innerText = 'test';
        document.body.appendChild(text);
        const originalWidth = text.getBoundingClientRect().width;
        const style = document.createElement('style');
        style.type = 'text/css';
        const fontURI = testURI('resource', 'font', key);
        style.innerHTML = `@font-face {font-family: "myFont"; src: url("${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);
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const response = await fetch(
          testURI('ctr', 'page', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        iframe.addEventListener('load', () => resolve(key), { once: true });
        iframe.src = testURI('resource', 'page', key);
      })
read: async (key) => {
        const iframe = document.createElement('iframe');
        document.body.appendChild(iframe);
        const iframeLoadPromise = new Promise((resolve, reject) => {
          iframe.addEventListener('load', resolve, { once: true });
        });
        const address = testURI('resource', 'page', key);
        iframe.src = address;
        await iframeLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const response = await fetch(
          testURI('ctr', 'image', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        img.addEventListener('load', () => resolve(key), { once: true });
        img.src = testURI('resource', 'image', key);
      })
read: async (key) => {
        const img = document.createElement('img');
        document.body.appendChild(img);
        const imgLoadPromise = new Promise((resolve, reject) => {
          img.addEventListener('load', resolve, { once: true });
        });
        img.src = testURI('resource', 'image', key);
        await imgLoadPromise;
        const 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:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
result, different session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_3p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_3p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_3p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_3p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_3p
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:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
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:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure
result, different session:
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure,
Error: IDBFactory.open: The operation is insecure
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: async (secret) => {
        try {
          return await IdbKeyVal.set('secret', secret);
        } catch (e) {
          throw new Error('Unsupported');
        }
      }
read: () => IdbKeyVal.get('secret')
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
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) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
result, different session:
61ac0a7a-b523-4ffb-bf70-405b3e8b5984_3p,
272bd7fb-b9de-434f-b799-28b37bfd0008_3p,
22e67ac7-a16d-4dc9-a9a6-3e6a061cac70_3p,
9d4da305-54b8-41ae-ad16-74257c77554c_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
result, different session:
c92c73d8-1be6-4282-aedd-e03224a6719e_3p,
fdc2e9f3-5586-414c-b177-8519bfd93e38_3p,
7211820c-8fb8-4a11-958e-a6381d16a81f_3p
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Passed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
eefd03c2-1231-4138-baa4-774d3158e5c8_3p,
2a5056df-98d2-455f-a8a7-b45c830bc0d0_3p,
00d14dd7-0ffd-445a-ae68-93d6c39639e8_3p,
59861472-4ebe-4a6d-abf8-18dd53621bb1_3p,
80ea1c6c-1ef5-448e-9859-0e10932ef44c_3p
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) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
result, different session:
edc596d6-abea-4bd4-8a0a-f69054097830_3p,
607f6857-5ef2-4551-8573-7583c41da544_3p,
7df89f73-4b25-400d-91c1-37620c91f3d0_3p,
6be1d4ea-8dd2-4d34-9e4c-0b5dd00c8859_3p
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
result, different session:
9d32dcf8-7361-494a-a7f8-4fb1ebf2b752_3p,
c6d7250c-ba10-4b12-9cd7-e0d5f8590de9_3p,
3c46d620-e1ba-49e0-91c2-27ad388d29f4_3p,
52418b24-aec4-44ef-bc76-c31a2df82aea_3p,
e4703191-67f3-4fef-9f47-7d291112febd_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
result, different session:
e0ecbcf7-7e51-43e7-8f7d-7ceb83a4bdf2_3p,
16557a9d-77e9-4669-8e8b-3baa065f318d_3p,
136045ff-53a3-4f13-b463-96abc637e1eb_3p,
551b76fd-39ee-437d-9fc1-399802c32d92_3p,
b368155e-74b3-4d0c-a908-4c63d83e07b5_3p
unsupported: false, false, false, false, false
passed: false, false, false, false, false
test failed: false, false, false, false, false
Unsupported
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
result, different session:
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.,
Error: The operation is insecure.
unsupported: true, true, true, true, true
passed: undefined
test failed: false, false, false, false, false
Failed
write: (secret) => { window.localStorage.setItem('secret', secret); }
read: () => window.localStorage.getItem('secret')
result, same session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
result, different session:
bf38f82d-30bf-4fd4-a84a-5024eed10525_3p,
91d18093-e75b-49cd-a5fc-fcb5a4a4d8f7_3p,
b444ef2d-6d5a-4166-98ab-5d8194392be2_3p,
4f7d4a70-5444-419c-ba6d-d959606a4e16_3p,
922670be-c546-4202-a5b2-fb69048675b6_3p
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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Unsupported
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const countString = (await response.text()).trim();
        if (parseInt(countString) === 0) {
          throw new Error('No requests received');
        }
        return countString;
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        return key;
      }
read: async (key) => {
        const link = document.createElement('link');
        link.rel = 'prefetch';
        link.href = testURI('resource', 'prefetch', key);
        document.getElementsByTagName('head')[0].appendChild(link);
        await sleepMs(500);
        const response = await fetch(
          testURI('ctr', 'prefetch', key), { cache: 'reload' });
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const response = await fetch(
          testURI('ctr', 'script', key), { cache: 'reload' });
        return (await response.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: (key) => new Promise((resolve, reject) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        script.addEventListener('load', () => resolve(key), { once: true });
        script.src = testURI('resource', 'script', key);
      })
read: async (key) => {
        const script = document.createElement('script');
        document.body.appendChild(script);
        const scriptLoadPromise = new Promise((resolve, reject) => {
          script.addEventListener('load', resolve, { once: true });
        });
        script.src = testURI('resource', 'script', key);
        await scriptLoadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1
result, different session: 1, 1, 1
unsupported: false, false, false
passed: false, false, false
test failed: false, false, false
Failed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const countResponse = await fetch(testURI('ctr', 'xhr', key),
          { cache: 'reload' });
        return (await countResponse.text()).trim();
      }
result, same session: 1, 1, 1, 1
result, different session: 1, 1, 1, 1
unsupported: false, false, false, false
passed: false, false, false, false
test failed: false, false, false, false
Failed
write: async (key) => {
        const req = new window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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 window.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 window.XMLHttpRequest();
        const loadPromise = new Promise(resolve => req.addEventListener('load', resolve));
        req.open('GET', testURI('resource', 'xhr', key));
        req.send();
        await loadPromise;
        const 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
DNS privacy testsWhich browsers keep their DNS queries encrypted?
The Domain Name System (DNS) is the method by which web browsers look up the IP address for each website you visit. In a DNS query, a web browser will ask a DNS resolver (somewhere on the internet) for the IP address corresponding to a domain name (such as nytimes.com) for a website you want to visit. Traditionally, most web browsers have sent their DNS queries unencrypted, which means your ISP or anyone else on the network between your computer and the DNS resolver can eavesdrop on the websites you visit. In recent years, web browsers and operating systems have begun to introduce encrypted DNS, including the DNS over HTTPS (DoH) protocol, to encrypt the DNS request from your browser and the response from the resolver to keep your browsing history from leaking. These tests check whether a browser is still protecting its DNS requests by sending them encrypted.
Location: Brazil
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Brazil.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Location: China
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in China.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Location: Germany
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Germany.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Location: India
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in India.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Location: Nigeria
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Nigeria.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Location: Russia
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in Russia.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Location: United States
  Checks whether the browser decides to use
  encrypted DNS if the computer is located in United States.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
OS DNS: Cloudflare
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Cloudflare.
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true
leak detected: false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
OS DNS: Comodo
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Comodo.
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
OS DNS: Google
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Google.
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true
leak detected: false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
OS DNS: Quad9
  Checks whether the browser decides to use
  encrypted DNS if the operating system's default DNS provider is Quad9.
Passed
passed: true, true, true, true
leak detected: false, false, false, false
Failed
passed: false, false, false
leak detected: true, true, true
Failed
passed: true, true, false, true, true
leak detected: false, false, true, false, false
Failed
passed: false, false, false, false
leak detected: true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true
Passed
passed: true, true, true, true, true
leak detected: false, false, false, false, false
Failed
passed: false, false, false, false, false
leak detected: true, true, true, true, true