(default settings)
|
brave 1.66 |
chrome 124.0 |
duckduckgo 1.58 |
edge 124.0 |
firefox 124.0a1 |
opera 110.0 |
safari 17.4 |
tor 13.5a5 |
vivaldi 6.6 |
---|---|---|---|---|---|---|---|---|---|
State Partitioning testsWhich browsers isolate websites to prevent them from sharing data to track you?
A common vulnerability of web browsers is that they allow tracking companies to 'tag' your browser with some data ('state') that identifies you. When third-party trackers are embedded in websites, they can see this identifying data as you browse to different websites. Fortunately, it is possible for this category of leaks to be fixed by partitioning all data stored in the browser such that no data can be shared between websites. | |||||||||
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned. | write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: h3 result, different first party: h2 unsupported: false passed: true test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: h3 result, different first party: h2 unsupported: false passed: true test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: Error: Unsupported result, different first party: h3 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: h3 result, different first party: h2 unsupported: false passed: true test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: h3 result, different first party: h2 unsupported: false passed: true test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: h3 result, different first party: h2 unsupported: false passed: true test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: Error: Unsupported result, different first party: h3 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: Error: Unsupported result, different first party: h2 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same first party: h3 result, different first party: h2 unsupported: false passed: true test failed: false |
blob
A 'blob URL' is a local reference to some raw data. Trackers can use a blob URL to share data between websites. | write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: Error: Failed to fetch unsupported: false passed: true test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 unsupported: false passed: false test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: Error: Load failed unsupported: false passed: true test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 unsupported: false passed: false test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: Error: NetworkError when attempting to fetch resource. unsupported: false passed: true test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 unsupported: false passed: false test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: Error: Load failed unsupported: false passed: true test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: Error: NetworkError when attempting to fetch resource. unsupported: false passed: true test failed: false |
write: (secret) => { try { let blobURL = URL.createObjectURL(new Blob([secret])); fetch(`${baseURI}blob?mode=write&key=${secret}&blobUrl=${encodeURIComponent(blobURL)}`); } catch (e) { throw new Error("Unsupported"); } } read: async (secret) => { let response = await fetch(`${baseURI}blob?mode=read&key=${secret}`); let result = await response.json(); let blobUrl = decodeURIComponent(result.blobUrl); let blobResponse = await fetch(blobUrl); return blobResponse.text(); } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b unsupported: false passed: false test failed: false |
BroadcastChannel
A BroadcastChannel is designed to send messages between tabs. In some browsers it can be used for cross-site communication and tracking. | write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: Error: The operation is insecure. unsupported: false passed: true test failed: false |
write: (secret) => { try { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data === "request") { bc.postMessage(secret); } }; } catch (e) { throw new Error("Unsupported"); } } read: () => new Promise((resolve, reject) => { let bc = new BroadcastChannel("secrets"); bc.onmessage = (event) => { if (event.data !== "request") { resolve(event.data); } }; bc.postMessage("request"); setTimeout(() => reject({message: "no BroadcastChannel message"}), 3000); }) result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: Error: no BroadcastChannel message unsupported: false passed: true test failed: 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. | write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: Error: Cannot read properties of undefined (reading 'url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: Error: Cannot read properties of undefined (reading 'url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: Error: undefined is not an object (evaluating 'cacheKeys[0].url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: Error: Cannot read properties of undefined (reading 'url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: Error: can't access property "url", cacheKeys[0] is undefined unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: Error: Cannot read properties of undefined (reading 'url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: c29ade6f-6e91-4000-9582-ca243d4f2894 result, different first party: Error: undefined is not an object (evaluating 'cacheKeys[0].url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: Error: The operation is insecure. result, different first party: Error: The operation is insecure. unsupported: true passed: undefined test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: Error: Cannot read properties of undefined (reading 'url') unsupported: false passed: true test failed: 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. | write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_http result, different first party: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167_http result, different first party: eac80989-abd5-4d75-ab7d-bc4b3f378167_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff_http result, different first party: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_http result, different first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243_http result, different first party: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0_http result, different first party: e91cf262-3db2-4ce2-9312-b912493f0ef0_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: e54f56ee-527d-4b84-847f-9120b105376f_http result, different first party: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557_http result, different first party: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_http result, different first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_http unsupported: false passed: false test failed: false |
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them. | write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_js result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167_js result, different first party: eac80989-abd5-4d75-ab7d-bc4b3f378167_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff_js result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_js result, different first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: eb0dda01-983e-40e8-b21b-217f51793243_js result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0_js result, different first party: e91cf262-3db2-4ce2-9312-b912493f0ef0_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: e54f56ee-527d-4b84-847f-9120b105376f_js result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557_js result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_js result, different first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_js unsupported: false passed: false test failed: false |
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers. | 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: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: null unsupported: false passed: true test failed: false |
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: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same first party: Error: Unsupported result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same first party: Error: Unsupported result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same first party: Error: Unsupported result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same first party: Error: Unsupported result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b unsupported: false passed: false test failed: false |
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites. | write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_7084186771363319 result, different first party: fake_2272268145888534 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_21618859912707467 result, different first party: fake_6085189803194619 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_09015397484328402 result, different first party: fake_723254404909278 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_069659341979881 result, different first party: fake_44882225731218006 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_20560520785469372 result, different first party: fake_8807832781452121 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_4695818784434147 result, different first party: fake_23259600374557454 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_28830244094653334 result, different first party: fake_027602366614611462 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_7501252736103019 result, different first party: fake_09433906170588457 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same first party: fake_5008356581461926 result, different first party: fake_6992584555094215 unsupported: false passed: true test failed: 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. | write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: 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. | write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking. | write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
getDirectory
navigator.storage.getDirectory exposes a location for storing files to web content. In some cases, these files may be shared across tabs. | 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: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
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: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { const root = await navigator.storage.getDirectory(); const fileHandle = await root.getFileHandle("secret.txt", { create: true }); const stream = await fileHandle.createWritable(); await stream.write(secret); await stream.close(); } catch (e) { throw new Error("Unsupported"); } } read: async () => { try { const root = await navigator.storage.getDirectory(); const fileHandle = await root.getFileHandle("secret.txt"); const file = await fileHandle.getFile(); return file.text(); } catch (e) { throw new Error("Unsupported"); } } result, same first party: result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
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: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
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: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { const root = await navigator.storage.getDirectory(); const fileHandle = await root.getFileHandle("secret.txt", { create: true }); const stream = await fileHandle.createWritable(); await stream.write(secret); await stream.close(); } catch (e) { throw new Error("Unsupported"); } } read: async () => { try { const root = await navigator.storage.getDirectory(); const fileHandle = await root.getFileHandle("secret.txt"); const file = await fileHandle.getFile(); return file.text(); } catch (e) { throw new Error("Unsupported"); } } result, same first party: result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
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 result, different first party: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: Error: Unsupported unsupported: false passed: true test failed: 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. | write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h1.privacytests2.org:8901/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h1.privacytests2.org:8901/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: unsupported: false passed: true test failed: false |
H2 connection
HTTP/2 is a web connection protocol introduced in 2015. Some browsers re-use HTTP/2 connections across websites and can thus be used to track users. | write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { await fetch(`https://h2.privacytests2.org:8902/?mode=write&secret=${secret}`, {cache: "no-store"}); } read: async () => { let response = await fetch(`https://h2.privacytests2.org:8902/?mode=read`, {cache: "no-store"}); return await response.text(); } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: unsupported: false passed: true test failed: 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. | write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: cda8b990c968a783d790834770c8106a result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: bc7bb090ba7241b3ba229223dc8617df result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: 985d1c56c0f012885dd851fc876483ec result, different first party: 97525ec66818ffd152170115d636edf8 unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: f27d550b5594e10d63b26594a7189ca9 result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: 3f627d4365f2252859641bbc2f6684fb result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: 284c99850ada91874e9986cac8ee2fae result, different first party: unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: 5a8300c423ffdf71339d83050a0e2d5b result, different first party: 68236f85cb634fe16c1f8e6e0b6be6ab unsupported: false passed: true test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: result, different first party: unsupported: true passed: undefined test failed: false |
write: async (secret) => { // Ensure that we can switch over to h3 via alt-svc: for (let i = 0; i<3; ++i) { await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); await sleepMs(500); } // Are we now connecting over h3? let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`, {cache: "no-store"}); let text = await response.text(); // Empty response text indicates we are not connecting over h3: if (text.trim() === "") { throw new Error("Unsupported"); } } read: async () => { let response = await fetch(`https://h3.privacytests2.org:4434/connection_id`); return await response.text(); } result, same first party: acf19d1e85798ac8935bb15d5539da44 result, different first party: unsupported: false passed: true test failed: false |
HSTS cache
The HTTP Strict-Transport-Security response header allows a website to signal that it should only be accessed via HTTPS. The browser remembers this directive in a database, but if this database is not partitioned, then it can be used to track users across websites." | write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: null read: null result, same first party: null result, different first party: HTTPS used by default; no HSTS cache issue expected unsupported: null passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
HSTS cache (fetch)
The HTTP Strict-Transport-Security response header allows a website to signal that it should only be accessed via HTTPS. The browser remembers this directive in a database, but if this database is not partitioned, then it can be used to track users across websites." | write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Used http unsupported: false passed: true test failed: false |
write: null read: null result, same first party: null result, different first party: HTTPS used by default; no HSTS cache issue expected unsupported: null passed: true test failed: false |
write: set HSTS flag read: read HSTS flag result, same first party: not tested result, different first party: Upgraded to https unsupported: false passed: false test failed: 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. | write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: 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. | write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: 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. | write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: Error: The operation is insecure. unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: undefined unsupported: false passed: true test failed: 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. | write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: Error: The operation is insecure. unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: null unsupported: false passed: true test failed: 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. | write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: Error: Cannot read properties of undefined (reading 'name') unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: Error: Cannot read properties of undefined (reading 'name') unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: Error: undefined is not an object (evaluating 'queryResult.held[0].name') unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: Error: Cannot read properties of undefined (reading 'name') unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: Error: LockManager.query: query() is not allowed in this context unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: Error: Cannot read properties of undefined (reading 'name') unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: Error: undefined is not an object (evaluating 'queryResult.held[0].name') unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: Error: LockManager.query: query() is not allowed in this context unsupported: false passed: true test failed: false |
write: async (key) => { if (navigator.locks) { navigator.locks.request(key, lock => new Promise((f,r) => {})); let queryResult = await navigator.locks.query(); return queryResult.held[0].clientId; } else { throw new Error("Unsupported"); } } read: async () => { if (navigator.locks) { let queryResult = await navigator.locks.query(); return queryResult.held[0].name; } } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: Error: Cannot read properties of undefined (reading 'name') unsupported: false passed: true test failed: 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. | write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: Error: No requests received result, different first party: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: Error: No requests received result, different first party: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: Error: No requests received result, different first party: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: 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. | write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
ServiceWorker
The ServiceWorker API allows websites to run code in the background and store content in the browser for offline use. If a ServiceWorker can be accessed from multiple websites, it can be abused to track users across sites. | write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: <html> <head><title>404 Not Found</title></head> <body> <center><h1>404 Not Found</h1></center> <hr><center>nginx/1.18.0 (Ubuntu)</center> </body> </html> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> result, different first party: unsupported: false passed: true test failed: false |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: <html> <head><title>404 Not Found</title></head> <body> <center><h1>404 Not Found</h1></center> <hr><center>nginx/1.18.0 (Ubuntu)</center> </body> </html> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> result, different first party: unsupported: false passed: true test failed: false |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: result, different first party: unsupported: false passed: undefined test failed: true |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: <html> <head><title>404 Not Found</title></head> <body> <center><h1>404 Not Found</h1></center> <hr><center>nginx/1.18.0 (Ubuntu)</center> </body> </html> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> result, different first party: unsupported: false passed: true test failed: false |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: result, different first party: unsupported: false passed: undefined test failed: true |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: <html> <head><title>404 Not Found</title></head> <body> <center><h1>404 Not Found</h1></center> <hr><center>nginx/1.18.0 (Ubuntu)</center> </body> </html> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> result, different first party: unsupported: false passed: true test failed: false |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: result, different first party: unsupported: false passed: undefined test failed: true |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: Error: navigator.serviceWorker is undefined result, different first party: Error: navigator.serviceWorker is undefined unsupported: true passed: undefined test failed: false |
write: async (key) => { if (!navigator.serviceWorker) { throw new Error("Unsupported"); } let registration = await navigator.serviceWorker.register( 'serviceWorker.js'); console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); await fetch(`serviceworker-write?secret=${key}`); } read: async () => { console.log("trying to register the serviceworker now..."); const registration = await Promise.race([ navigator.serviceWorker.register('serviceWorker.js'), sleepMs(500) ]); if (registration === undefined) { // We timed out or otherwise failed. throw new Error("ServiceWorker registration failed"); } console.log(registration); await navigator.serviceWorker.ready; console.log("service worker ready"); await sleepMs(100); let response = await fetch("serviceworker-read"); return await response.text(); } result, same first party: <html> <head><title>404 Not Found</title></head> <body> <center><h1>404 Not Found</h1></center> <hr><center>nginx/1.18.0 (Ubuntu)</center> </body> </html> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> <!-- a padding to disable MSIE and Chrome friendly error page --> result, different first party: unsupported: false passed: true test failed: 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. | write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: Error: Unsupported unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: Error: The operation is insecure. unsupported: false passed: true test failed: false |
write: async (secret) => { try { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); // console.log("worker", worker); const messagePromise = new Promise((resolve) => { worker.port.onmessage = (e) => resolve(e.data); }); worker.port.postMessage(secret); await messagePromise; } catch (e) { throw new Error("Unsupported"); } } read: async () => { let worker = new SharedWorker("supercookies_sharedworker.js"); worker.port.start(); const messagePromise = new Promise((resolve, reject) => { worker.port.onmessage = (e) => resolve(e.data); setTimeout(() => reject(new Error("no SharedWorker message received")), 200); }); worker.port.postMessage("request"); const message = await messagePromise; if (message === "none") { throw new Error("Unsupported"); } return message; } result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: Error: Unsupported unsupported: false passed: true test failed: 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. | write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: 96b8404f3f76e69bd60330169ab3f6863f4d63a4a5c6fde8f707482e0ecc000f result, different first party: cdc5949a89ef8a766b2129202344eb9067dc500d014cb626be4484d827ca6b78 unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: 5587909efde26f817917103f584466698daef951db94bf5146e493ff6056017c result, different first party: 43d2a0a80996a1553fbbe2511b8aa06eb67d6a650acd6c7454df121ccc78da50 unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: 28cf4b1862cfddf1ee908ea67bdce1f5adc851f35eee15d73d982cfa61ae304e result, different first party: 2ad650b09d4d7089158430236c22345a35efe400857b38782056b296448fc56d unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: 826e9efdd0cc1a9bfd4ffe5dee7717929e80aa43dfb44bc61d6176042693222a result, different first party: fec5df1f8d5a319ef6438177b6ec2253774b60c0cbadb07af232a130d858200e unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: e7ece0e172b517831dcedd22e60aaa4a3b5e72c85920df07ebf30363cc2adb84 result, different first party: 7f0595e99dced9f56e5ab89df194be2885172b176a71a6c01942d21b0eeff1ff unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: 0d71488817e1fb4595bce13bc16230b7d4153d4b5994ff40f41c2c4a736703d9 result, different first party: a31d2922fe2ce8969ad1eae5d648b65f7e7ddfa13b0a80dce0f47e19cd330866 unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: e6abcf18fd6132eab93494282c98dfc44a91023ee47c9cccd6a87e547e2e44d8 result, different first party: ac1f6bdc8b3030632a5b592b262c605d0a3d85b3e49c9c2024c91524c335a625 unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: d547101b20285ec2a153283f9a5e3daa580be2ce3e23c89a8eb4b0d4810810d1 result, different first party: e0086c2d09026296a755a58fe5977e230ba82fbd4fbb97fb59c503958264ddc2 unsupported: false passed: true test failed: false |
write: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } read: async () => { let results = await fetch("https://tls.privacytests2.org:8900/"); return (await results.json()).sessionId; } result, same first party: bdbe1b14ad19762b6c1931931bd39b6bf0d395979d1cb7093719a64449dc318e result, different first party: b333f64ff58310b99986950f6a44abba2171df8c17d5fd57cf8202094ef30b4e unsupported: false passed: true test failed: 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. | write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 2 result, different first party: 3 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same first party: 1 result, different first party: 2 unsupported: false passed: true test failed: 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. | write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: false |
write: (secret) => { /* do nothing */ } read: () => document.referrer result, same first party: https://test-pages.privacytests2.org/ result, different first party: https://test-pages.privacytests2.org/ unsupported: false passed: false test failed: 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. | write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: 8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: e54f56ee-527d-4b84-847f-9120b105376f result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: 80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: null unsupported: false passed: true test failed: false |
write: (secret) => sessionStorage.setItem("secret", secret) read: () => sessionStorage.getItem("secret") result, same first party: 5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: null unsupported: false passed: true test failed: 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. | write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_f7e729f7-9e22-4b1b-baa7-038cdd2b7466 result, different first party: unsupported: false passed: true test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_eac80989-abd5-4d75-ab7d-bc4b3f378167 result, different first party: name_eac80989-abd5-4d75-ab7d-bc4b3f378167 unsupported: false passed: false test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_8dcf3049-0641-4832-bc66-2373dea8b2ff result, different first party: unsupported: false passed: true test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_25ffccc7-68bd-4d2f-86e0-8a0bb87be277 result, different first party: name_25ffccc7-68bd-4d2f-86e0-8a0bb87be277 unsupported: false passed: false test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_eb0dda01-983e-40e8-b21b-217f51793243 result, different first party: unsupported: false passed: true test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_e91cf262-3db2-4ce2-9312-b912493f0ef0 result, different first party: name_e91cf262-3db2-4ce2-9312-b912493f0ef0 unsupported: false passed: false test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_e54f56ee-527d-4b84-847f-9120b105376f result, different first party: unsupported: false passed: true test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_80df2b1d-cc96-4f9a-8af8-418737aa9557 result, different first party: unsupported: false passed: true test failed: false |
write: (secret) => window.name = "name_" + secret read: () => window.name result, same first party: name_5c4b21b3-6581-43d2-8006-dc5d38ff986b result, different first party: name_5c4b21b3-6581-43d2-8006-dc5d38ff986b unsupported: false passed: false test failed: false |
HTTPS testsWhich browsers prevent unencrypted network connections?
HTTPS is the protocol that web browsers use to connect securely to websites. When HTTPS is being used, the connection is encrypted so that third parties on the network cannot read content being sent between the server and your browser. In the past, insecure connections were the default and websites would need to actively request that a browser use HTTPS. Now the status quo is shifting, and browser makers are moving toward a world where HTTPS is the default protocol.` | |||||||||
Insecure website warning
Checks to see if the browser stops loading an insecure website and warns the user before giving them the option to continue. Known as HTTPS-Only Mode in some browsers. | passed: false result: Insecure website loaded |
passed: false result: Insecure website loaded |
passed: false result: Insecure website loaded |
passed: false result: Insecure website loaded |
passed: false result: Insecure website loaded |
passed: false result: Insecure website loaded |
passed: false result: Insecure website loaded |
passed: true result: Insecure website never loaded |
passed: false result: 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. | upgraded: true passed: true |
upgraded: true passed: true |
upgraded: false passed: false |
upgraded: true passed: true |
upgraded: false passed: false |
upgraded: true passed: true |
upgraded: false passed: false |
upgraded: true passed: true |
upgraded: true passed: 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. | upgraded: true passed: true |
upgraded: true passed: true |
upgraded: false passed: false |
upgraded: true passed: true |
upgraded: false passed: false |
upgraded: true passed: true |
upgraded: false passed: false |
upgraded: true passed: true |
upgraded: true passed: true |
Upgradable image
Checks to see if the browser attempts to upgrade an insecure address for an image to HTTPS whenever possible. | passed: true result: upgraded |
passed: true result: upgraded |
passed: false result: loaded insecurely |
passed: true result: upgraded |
passed: true result: upgraded |
passed: true result: upgraded |
passed: true result: upgraded |
passed: true result: upgraded |
passed: true result: upgraded |
Upgradable script
Checks to see if the browser attempts to upgrade an insecure address for an script to HTTPS whenever possible. | passed: true result: blocked |
passed: true result: blocked |
passed: true result: blocked |
passed: true result: blocked |
passed: true result: blocked |
passed: true result: blocked |
passed: true result: blocked |
passed: true result: upgraded |
passed: true result: 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. | SNI_status: encrypted passed: true |
SNI_status: encrypted passed: true |
SNI_status: plaintext passed: false |
SNI_status: encrypted passed: true |
SNI_status: encrypted passed: true |
SNI_status: encrypted passed: true |
SNI_status: plaintext passed: false |
SNI_status: plaintext passed: false |
SNI_status: encrypted passed: 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. | header value: 1 passed: true |
header value: undefined passed: false |
header value: undefined passed: false |
header value: undefined passed: false |
header value: undefined passed: false |
header value: undefined passed: false |
header value: undefined passed: false |
header value: undefined passed: false |
header value: undefined passed: 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. | sec-gpc: 1 passed: true |
passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
IP address leak
IP addresses can be used to uniquely identify a large percentage of users. A proxy, VPN, or Tor can mask a user's IP address. | passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
passed: false |
passed: true |
passed: false |
Stream isolation
Browsers that use Tor can use a different Tor circuit per top-level website. | write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: false readSameFirstParty: 2605:6400:30:f174:1111:2222:3333:4444 readDifferentFirstParty: 2001:67c:6ec:203:192:42:116:186 passed: true testFailed: false |
write: () => { if (!usingTor) { throw new Error("Unsupported"); } } read: async () => { if (usingTor) { return ipAddress; } else { throw new Error("Unsupported"); } } unsupported: true readSameFirstParty: Error: Unsupported readDifferentFirstParty: Error: Unsupported testFailed: 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. | IsTorExit: false passed: false |
IsTorExit: false passed: false |
IsTorExit: false passed: false |
IsTorExit: false passed: false |
IsTorExit: false passed: false |
IsTorExit: false passed: false |
IsTorExit: false passed: false |
IsTorExit: true passed: true |
IsTorExit: false passed: false |
Fingerprinting resistance testsWhich browsers hide what's unique about your device?
Fingerprinting is a technique trackers use to uniquely identify you as you browse the web. A fingerprinting script will measure several characteristics of your browser and, combining this data, will build a fingerprint that may uniquely identify you among web users. Browsers can introduce countermeasures, such as minimizing the distinguishing information disclosed by certain web APIs so your browser is harder to pick out from the crowd (so-called 'fingerprinting resistance').`, | |||||||||
Media query screen height
Height of the user's screen in pixels. | expression: undefined desired expression: undefined actual value: 1293 desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 900 desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: 1440 desired value: undefined passed: false |
Media query screen width
Width of the user's screen in pixels. | expression: undefined desired expression: undefined actual value: 1164 desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: 1400 desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: 2560 desired value: undefined passed: false |
outerHeight
Height of the browser window in pixels, including browser chrome. | expression: outerHeight desired expression: undefined actual value: 1293 desired value: undefined passed: true |
expression: outerHeight desired expression: undefined actual value: 1371 desired value: undefined passed: false |
expression: outerHeight desired expression: undefined actual value: 703 desired value: undefined passed: true |
expression: outerHeight desired expression: undefined actual value: 1371 desired value: undefined passed: false |
expression: outerHeight desired expression: undefined actual value: 1040 desired value: undefined passed: false |
expression: outerHeight desired expression: undefined actual value: 1061 desired value: undefined passed: false |
expression: outerHeight desired expression: undefined actual value: 940 desired value: undefined passed: false |
expression: outerHeight desired expression: undefined actual value: 900 desired value: undefined passed: true |
expression: outerHeight desired expression: undefined actual value: 1371 desired value: undefined passed: false |
screen.height
Height of the user's screen, in pixels. | expression: screen.height desired expression: undefined actual value: 1293 desired value: undefined passed: true |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screen.height desired expression: undefined actual value: 900 desired value: undefined passed: true |
expression: screen.height desired expression: undefined actual value: 1440 desired value: undefined passed: false |
screen.width
Width of the user's screen, in pixels. | expression: screen.width desired expression: undefined actual value: 1164 desired value: undefined passed: true |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
expression: screen.width desired expression: undefined actual value: 1400 desired value: undefined passed: true |
expression: screen.width desired expression: undefined actual value: 2560 desired value: undefined passed: false |
screenX
Position, in pixels, of the left edge of the browser window on screen. | expression: screenX desired expression: undefined actual value: 8 desired value: undefined passed: true |
expression: screenX desired expression: undefined actual value: 22 desired value: undefined passed: false |
expression: screenX desired expression: undefined actual value: 0 desired value: undefined passed: true |
expression: screenX desired expression: undefined actual value: 22 desired value: undefined passed: false |
expression: screenX desired expression: undefined actual value: 642 desired value: undefined passed: false |
expression: screenX desired expression: undefined actual value: 320 desired value: undefined passed: false |
expression: screenX desired expression: undefined actual value: 340 desired value: undefined passed: false |
expression: screenX desired expression: undefined actual value: 0 desired value: undefined passed: true |
expression: screenX desired expression: undefined actual value: 22 desired value: undefined passed: false |
screenY
Position, in pixels, of the top edge of the browser window on screen. | expression: screenY desired expression: undefined actual value: 0 desired value: undefined passed: true |
expression: screenY desired expression: undefined actual value: 47 desired value: undefined passed: false |
expression: screenY desired expression: undefined actual value: 1440 desired value: undefined passed: false |
expression: screenY desired expression: undefined actual value: 47 desired value: undefined passed: false |
expression: screenY desired expression: undefined actual value: 355 desired value: undefined passed: false |
expression: screenY desired expression: undefined actual value: 202 desired value: undefined passed: false |
expression: screenY desired expression: undefined actual value: 500 desired value: undefined passed: false |
expression: screenY desired expression: undefined actual value: 0 desired value: undefined passed: true |
expression: screenY desired expression: undefined actual value: 47 desired value: undefined passed: false |
System font detection
Web pages can detect the presence of a font installed on the user's system. The presence or absence of various fonts is commonly used to fingerprint users. | expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: false |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: true |
expression: undefined desired expression: undefined actual value: undefined desired value: undefined passed: 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: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
__hssc
HubSpot tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
__hstc
HubSpot tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
__s
Drip.com email address tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
_hsenc
HubSpot tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
_openstat
Yandex tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
dclid
DoubleClick Click ID (Google) | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
fbclid
Facebook Click Identifier | passed: true |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
gclid
Google Click Identifier | passed: true |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
hsCtaTracking
HubSpot tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
mc_eid
Mailchimp Email ID (email recipient's address) | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
mkt_tok
Adobe Marketo tracking parameter | passed: true |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
ml_subscriber
MailerLite email tracking | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
ml_subscriber_hash
MailerLite email tracking | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
msclkid
Microsoft Click ID | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
oly_anon_id
Omeda marketing 'anonymous' customer id | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
oly_enc_id
Omeda marketing 'known' customer id | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
rb_clickid
Unknown high-entropy tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
s_cid
Adobe Site Catalyst tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
vero_conv
Vero tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
vero_id
Vero tracking parameter | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
wickedid
Wicked Reports e-commerce tracking | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
yclid
Yandex Click ID | passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: false |
value: 01752447911282684 passed: false |
passed: true |
value: 01752447911282684 passed: 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 | url: https://munchkin.marketo.net/munchkin.js passed: true |
url: https://munchkin.marketo.net/munchkin.js passed: false |
url: https://munchkin.marketo.net/munchkin.js passed: true |
url: https://munchkin.marketo.net/munchkin.js passed: false |
url: https://munchkin.marketo.net/munchkin.js passed: false |
url: https://munchkin.marketo.net/munchkin.js passed: false |
url: https://munchkin.marketo.net/munchkin.js passed: false |
url: https://munchkin.marketo.net/munchkin.js passed: false |
url: https://munchkin.marketo.net/munchkin.js passed: false |
Adobe Audience Manager
Tests whether the browser blocks the page from loading the tracker at https://dpm.demdex.net/ibs | url: https://dpm.demdex.net/ibs passed: true |
url: https://dpm.demdex.net/ibs passed: false |
url: https://dpm.demdex.net/ibs passed: true |
url: https://dpm.demdex.net/ibs passed: false |
url: https://dpm.demdex.net/ibs passed: false |
url: https://dpm.demdex.net/ibs passed: false |
url: https://dpm.demdex.net/ibs passed: false |
url: https://dpm.demdex.net/ibs passed: false |
url: https://dpm.demdex.net/ibs passed: false |
Amazon adsystem
Tests whether the browser blocks the page from loading the tracker at https://s.amazon-adsystem.com/dcm | url: https://s.amazon-adsystem.com/dcm passed: true |
url: https://s.amazon-adsystem.com/dcm passed: false |
url: https://s.amazon-adsystem.com/dcm passed: true |
url: https://s.amazon-adsystem.com/dcm passed: false |
url: https://s.amazon-adsystem.com/dcm passed: false |
url: https://s.amazon-adsystem.com/dcm passed: false |
url: https://s.amazon-adsystem.com/dcm passed: false |
url: https://s.amazon-adsystem.com/dcm passed: false |
url: https://s.amazon-adsystem.com/dcm passed: false |
AppNexus
Tests whether the browser blocks the page from loading the tracker at https://ib.adnxs.com/px?id=178248&t=1 | url: https://ib.adnxs.com/px?id=178248&t=1 passed: true |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: true |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
url: https://ib.adnxs.com/px?id=178248&t=1 passed: false |
Bing Ads
Tests whether the browser blocks the page from loading the tracker at https://bat.bing.com/bat.js | url: https://bat.bing.com/bat.js passed: true |
url: https://bat.bing.com/bat.js passed: false |
url: https://bat.bing.com/bat.js passed: true |
url: https://bat.bing.com/bat.js passed: false |
url: https://bat.bing.com/bat.js passed: false |
url: https://bat.bing.com/bat.js passed: false |
url: https://bat.bing.com/bat.js passed: false |
url: https://bat.bing.com/bat.js passed: false |
url: https://bat.bing.com/bat.js passed: false |
Chartbeat
Tests whether the browser blocks the page from loading the tracker at https://static.chartbeat.com/js/chartbeat.js | url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: true |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
url: https://static.chartbeat.com/js/chartbeat.js passed: false |
Criteo
Tests whether the browser blocks the page from loading the tracker at https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx | url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: true |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: true |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx passed: false |
DoubleClick (Google)
Tests whether the browser blocks the page from loading the tracker at https://securepubads.g.doubleclick.net/static/glade.js | url: https://securepubads.g.doubleclick.net/static/glade.js passed: true |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: true |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
url: https://securepubads.g.doubleclick.net/static/glade.js passed: false |
Facebook tracking
Tests whether the browser blocks the page from loading the tracker at https://connect.facebook.net/en_US/fbevents.js | url: https://connect.facebook.net/en_US/fbevents.js passed: true |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
url: https://connect.facebook.net/en_US/fbevents.js passed: true |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
url: https://connect.facebook.net/en_US/fbevents.js passed: false |
Google (third-party ad pixel)
Tests whether the browser blocks the page from loading the tracker at https://www.google.com/pagead/1p-user-list/ | url: https://www.google.com/pagead/1p-user-list/ passed: true |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
url: https://www.google.com/pagead/1p-user-list/ passed: true |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
url: https://www.google.com/pagead/1p-user-list/ passed: false |
Google Analytics
Tests whether the browser blocks the page from loading the tracker at https://google-analytics.com/urchin.js | url: https://google-analytics.com/urchin.js passed: true |
url: https://google-analytics.com/urchin.js passed: false |
url: https://google-analytics.com/urchin.js passed: true |
url: https://google-analytics.com/urchin.js passed: false |
url: https://google-analytics.com/urchin.js passed: false |
url: https://google-analytics.com/urchin.js passed: false |
url: https://google-analytics.com/urchin.js passed: false |
url: https://google-analytics.com/urchin.js passed: false |
url: https://google-analytics.com/urchin.js passed: false |
Google Tag Manager
Tests whether the browser blocks the page from loading the tracker at https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL | url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: true |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: true |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL passed: false |
Index Exchange
Tests whether the browser blocks the page from loading the tracker at https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 | url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: true |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: true |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 passed: false |
New Relic
Tests whether the browser blocks the page from loading the tracker at https://js-agent.newrelic.com/nr-1212.min.js | url: https://js-agent.newrelic.com/nr-1212.min.js passed: true |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: true |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
url: https://js-agent.newrelic.com/nr-1212.min.js passed: false |
Quantcast
Tests whether the browser blocks the page from loading the tracker at https://pixel.quantserve.com/pixel | url: https://pixel.quantserve.com/pixel passed: true |
url: https://pixel.quantserve.com/pixel passed: false |
url: https://pixel.quantserve.com/pixel passed: true |
url: https://pixel.quantserve.com/pixel passed: false |
url: https://pixel.quantserve.com/pixel passed: false |
url: https://pixel.quantserve.com/pixel passed: false |
url: https://pixel.quantserve.com/pixel passed: false |
url: https://pixel.quantserve.com/pixel passed: false |
url: https://pixel.quantserve.com/pixel passed: false |
Scorecard Research Beacon
Tests whether the browser blocks the page from loading the tracker at https://sb.scorecardresearch.com/internal-c2/default/cs.js | url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: true |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: true |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
url: https://sb.scorecardresearch.com/internal-c2/default/cs.js passed: false |
Taboola
Tests whether the browser blocks the page from loading the tracker at https://trc.taboola.com/futureplc-tomsguide/trc/3/json | url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: true |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: true |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json passed: false |
Twitter pixel
Tests whether the browser blocks the page from loading the tracker at https://t.co/i/adsct | url: https://t.co/i/adsct passed: true |
url: https://t.co/i/adsct passed: false |
url: https://t.co/i/adsct passed: true |
url: https://t.co/i/adsct passed: false |
url: https://t.co/i/adsct passed: false |
url: https://t.co/i/adsct passed: false |
url: https://t.co/i/adsct passed: false |
url: https://t.co/i/adsct passed: false |
url: https://t.co/i/adsct passed: false |
Yandex Ads
Tests whether the browser blocks the page from loading the tracker at https://yandex.ru/ads/system/header-bidding.js | url: https://yandex.ru/ads/system/header-bidding.js passed: true |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
url: https://yandex.ru/ads/system/header-bidding.js passed: true |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
url: https://yandex.ru/ads/system/header-bidding.js passed: false |
Tracking cookie protection testsWhich browsers block important known tracking cookies?
A large fraction of web pages on the web have hidden third-party trackers that read and write cookies in your browser. These cookies can be used to track your browsing across websites. This section checks to see if a browser stops cross-site tracking by cookies from 20 of the largest trackers listed by https://whotracks.me.`, | |||||||||
Adobe
Tests whether the browser stops cookies from munchkin.marketo.net from tracking users across websites. | passed: true url: https://munchkin.marketo.net/munchkin.js cookieFound: false |
passed: false url: https://munchkin.marketo.net/munchkin.js cookieFound: true |
passed: true url: https://munchkin.marketo.net/munchkin.js cookieFound: false |
passed: true url: https://munchkin.marketo.net/munchkin.js cookieFound: false |
passed: true url: https://munchkin.marketo.net/munchkin.js cookieFound: false |
passed: false url: https://munchkin.marketo.net/munchkin.js cookieFound: true |
passed: true url: https://munchkin.marketo.net/munchkin.js cookieFound: false |
passed: true url: https://munchkin.marketo.net/munchkin.js cookieFound: false |
passed: false url: https://munchkin.marketo.net/munchkin.js cookieFound: true |
Adobe Audience Manager
Tests whether the browser stops cookies from dpm.demdex.net from tracking users across websites. | passed: true url: https://dpm.demdex.net/ibs cookieFound: false |
passed: false url: https://dpm.demdex.net/ibs cookieFound: true |
passed: true url: https://dpm.demdex.net/ibs cookieFound: false |
passed: true url: https://dpm.demdex.net/ibs cookieFound: false |
passed: true url: https://dpm.demdex.net/ibs cookieFound: false |
passed: false url: https://dpm.demdex.net/ibs cookieFound: true |
passed: true url: https://dpm.demdex.net/ibs cookieFound: false |
passed: true url: https://dpm.demdex.net/ibs cookieFound: false |
passed: false url: https://dpm.demdex.net/ibs cookieFound: true |
Amazon adsystem
Tests whether the browser stops cookies from s.amazon-adsystem.com from tracking users across websites. | passed: true url: https://s.amazon-adsystem.com/dcm cookieFound: false |
passed: false url: https://s.amazon-adsystem.com/dcm cookieFound: true |
passed: true url: https://s.amazon-adsystem.com/dcm cookieFound: false |
passed: true url: https://s.amazon-adsystem.com/dcm cookieFound: false |
passed: true url: https://s.amazon-adsystem.com/dcm cookieFound: false |
passed: false url: https://s.amazon-adsystem.com/dcm cookieFound: true |
passed: true url: https://s.amazon-adsystem.com/dcm cookieFound: false |
passed: true url: https://s.amazon-adsystem.com/dcm cookieFound: false |
passed: false url: https://s.amazon-adsystem.com/dcm cookieFound: true |
AppNexus
Tests whether the browser stops cookies from ib.adnxs.com from tracking users across websites. | passed: true url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: false |
passed: false url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: true |
passed: true url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: false |
passed: false url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: true |
passed: true url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: false |
passed: false url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: true |
passed: true url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: false |
passed: true url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: false |
passed: false url: https://ib.adnxs.com/px?id=178248&t=1 cookieFound: true |
Bing Ads
Tests whether the browser stops cookies from bat.bing.com from tracking users across websites. | passed: true url: https://bat.bing.com/bat.js cookieFound: false |
passed: false url: https://bat.bing.com/bat.js cookieFound: true |
passed: true url: https://bat.bing.com/bat.js cookieFound: false |
passed: false url: https://bat.bing.com/bat.js cookieFound: true |
passed: true url: https://bat.bing.com/bat.js cookieFound: false |
passed: false url: https://bat.bing.com/bat.js cookieFound: true |
passed: true url: https://bat.bing.com/bat.js cookieFound: false |
passed: true url: https://bat.bing.com/bat.js cookieFound: false |
passed: false url: https://bat.bing.com/bat.js cookieFound: true |
Chartbeat
Tests whether the browser stops cookies from static.chartbeat.com from tracking users across websites. | passed: true url: https://static.chartbeat.com/js/chartbeat.js cookieFound: false |
passed: false url: https://static.chartbeat.com/js/chartbeat.js cookieFound: true |
passed: true url: https://static.chartbeat.com/js/chartbeat.js cookieFound: false |
passed: false url: https://static.chartbeat.com/js/chartbeat.js cookieFound: true |
passed: true url: https://static.chartbeat.com/js/chartbeat.js cookieFound: false |
passed: false url: https://static.chartbeat.com/js/chartbeat.js cookieFound: true |
passed: true url: https://static.chartbeat.com/js/chartbeat.js cookieFound: false |
passed: true url: https://static.chartbeat.com/js/chartbeat.js cookieFound: false |
passed: false url: https://static.chartbeat.com/js/chartbeat.js cookieFound: true |
Criteo
Tests whether the browser stops cookies from dis.criteo.com from tracking users across websites. | passed: true url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: false |
passed: false url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: true |
passed: true url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: false |
passed: true url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: false |
passed: true url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: false |
passed: false url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: true |
passed: true url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: false |
passed: true url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: false |
passed: false url: https://dis.criteo.com/dis/rtb/appnexus/cookiematch.aspx cookieFound: true |
DoubleClick (Google)
Tests whether the browser stops cookies from securepubads.g.doubleclick.net from tracking users across websites. | passed: true url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: false |
passed: false url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: true |
passed: true url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: false |
passed: true url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: false |
passed: true url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: false |
passed: false url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: true |
passed: true url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: false |
passed: true url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: false |
passed: false url: https://securepubads.g.doubleclick.net/static/glade.js cookieFound: true |
Facebook tracking
Tests whether the browser stops cookies from connect.facebook.net from tracking users across websites. | passed: true url: https://connect.facebook.net/en_US/fbevents.js cookieFound: false |
passed: false url: https://connect.facebook.net/en_US/fbevents.js cookieFound: true |
passed: true url: https://connect.facebook.net/en_US/fbevents.js cookieFound: false |
passed: true url: https://connect.facebook.net/en_US/fbevents.js cookieFound: false |
passed: true url: https://connect.facebook.net/en_US/fbevents.js cookieFound: false |
passed: false url: https://connect.facebook.net/en_US/fbevents.js cookieFound: true |
passed: true url: https://connect.facebook.net/en_US/fbevents.js cookieFound: false |
passed: true url: https://connect.facebook.net/en_US/fbevents.js cookieFound: false |
passed: false url: https://connect.facebook.net/en_US/fbevents.js cookieFound: true |
Google (third-party ad pixel)
Tests whether the browser stops cookies from www.google.com from tracking users across websites. | passed: true url: https://www.google.com/pagead/1p-user-list/ cookieFound: false |
passed: false url: https://www.google.com/pagead/1p-user-list/ cookieFound: true |
passed: true url: https://www.google.com/pagead/1p-user-list/ cookieFound: false |
passed: true url: https://www.google.com/pagead/1p-user-list/ cookieFound: false |
passed: true url: https://www.google.com/pagead/1p-user-list/ cookieFound: false |
passed: false url: https://www.google.com/pagead/1p-user-list/ cookieFound: true |
passed: true url: https://www.google.com/pagead/1p-user-list/ cookieFound: false |
passed: true url: https://www.google.com/pagead/1p-user-list/ cookieFound: false |
passed: false url: https://www.google.com/pagead/1p-user-list/ cookieFound: true |
Google Analytics
Tests whether the browser stops cookies from google-analytics.com from tracking users across websites. | passed: true url: https://google-analytics.com/urchin.js cookieFound: false |
passed: false url: https://google-analytics.com/urchin.js cookieFound: true |
passed: true url: https://google-analytics.com/urchin.js cookieFound: false |
passed: false url: https://google-analytics.com/urchin.js cookieFound: true |
passed: true url: https://google-analytics.com/urchin.js cookieFound: false |
passed: false url: https://google-analytics.com/urchin.js cookieFound: true |
passed: true url: https://google-analytics.com/urchin.js cookieFound: false |
passed: true url: https://google-analytics.com/urchin.js cookieFound: false |
passed: false url: https://google-analytics.com/urchin.js cookieFound: true |
Google Tag Manager
Tests whether the browser stops cookies from www.googletagmanager.com from tracking users across websites. | passed: true url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: false |
passed: false url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: true |
passed: true url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: false |
passed: false url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: true |
passed: true url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: false |
passed: false url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: true |
passed: true url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: false |
passed: true url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: false |
passed: false url: https://www.googletagmanager.com/gtag.js?id=GTM-NX4SMZL cookieFound: true |
Index Exchange
Tests whether the browser stops cookies from dsum-sec.casalemedia.com from tracking users across websites. | passed: true url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: false |
passed: false url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: true |
passed: true url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: false |
passed: true url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: false |
passed: true url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: false |
passed: false url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: true |
passed: true url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: false |
passed: true url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: false |
passed: false url: https://dsum-sec.casalemedia.com/crum?cm_dsp_id=10&external_user_id=629685505537&C=1 cookieFound: true |
New Relic
Tests whether the browser stops cookies from js-agent.newrelic.com from tracking users across websites. | passed: true url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: false |
passed: false url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: true |
passed: true url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: false |
passed: false url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: true |
passed: true url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: false |
passed: false url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: true |
passed: true url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: false |
passed: true url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: false |
passed: false url: https://js-agent.newrelic.com/nr-1212.min.js cookieFound: true |
Quantcast
Tests whether the browser stops cookies from pixel.quantserve.com from tracking users across websites. | passed: true url: https://pixel.quantserve.com/pixel cookieFound: false |
passed: false url: https://pixel.quantserve.com/pixel cookieFound: true |
passed: true url: https://pixel.quantserve.com/pixel cookieFound: false |
passed: true url: https://pixel.quantserve.com/pixel cookieFound: false |
passed: true url: https://pixel.quantserve.com/pixel cookieFound: false |
passed: false url: https://pixel.quantserve.com/pixel cookieFound: true |
passed: true url: https://pixel.quantserve.com/pixel cookieFound: false |
passed: true url: https://pixel.quantserve.com/pixel cookieFound: false |
passed: false url: https://pixel.quantserve.com/pixel cookieFound: true |
Scorecard Research Beacon
Tests whether the browser stops cookies from sb.scorecardresearch.com from tracking users across websites. | passed: true url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: false |
passed: false url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: true |
passed: true url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: false |
passed: false url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: true |
passed: true url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: false |
passed: false url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: true |
passed: true url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: false |
passed: true url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: false |
passed: false url: https://sb.scorecardresearch.com/internal-c2/default/cs.js cookieFound: true |
Taboola
Tests whether the browser stops cookies from trc.taboola.com from tracking users across websites. | passed: true url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: false |
passed: false url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: true |
passed: true url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: false |
passed: true url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: false |
passed: true url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: false |
passed: false url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: true |
passed: true url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: false |
passed: true url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: false |
passed: false url: https://trc.taboola.com/futureplc-tomsguide/trc/3/json cookieFound: true |
Twitter pixel
Tests whether the browser stops cookies from t.co from tracking users across websites. | passed: true url: https://t.co/i/adsct cookieFound: false |
passed: false url: https://t.co/i/adsct cookieFound: true |
passed: true url: https://t.co/i/adsct cookieFound: false |
passed: false url: https://t.co/i/adsct cookieFound: true |
passed: true url: https://t.co/i/adsct cookieFound: false |
passed: false url: https://t.co/i/adsct cookieFound: true |
passed: true url: https://t.co/i/adsct cookieFound: false |
passed: true url: https://t.co/i/adsct cookieFound: false |
passed: false url: https://t.co/i/adsct cookieFound: true |
Yandex Ads
Tests whether the browser stops cookies from yandex.ru from tracking users across websites. | passed: true url: https://yandex.ru/ads/system/header-bidding.js cookieFound: false |
passed: false url: https://yandex.ru/ads/system/header-bidding.js cookieFound: true |
passed: true url: https://yandex.ru/ads/system/header-bidding.js cookieFound: false |
passed: true url: https://yandex.ru/ads/system/header-bidding.js cookieFound: false |
passed: true url: https://yandex.ru/ads/system/header-bidding.js cookieFound: false |
passed: false url: https://yandex.ru/ads/system/header-bidding.js cookieFound: true |
passed: true url: https://yandex.ru/ads/system/header-bidding.js cookieFound: false |
passed: true url: https://yandex.ru/ads/system/header-bidding.js cookieFound: false |
passed: false url: https://yandex.ru/ads/system/header-bidding.js cookieFound: true |
Cross-session first-party tracking testsWhich browsers prevent websites from tracking you across browser sessions?
A common vulnerability of web browsers is that they allow websites ("first parties") to 'tag' your browser with some tracking data. This tag can be used to re-identify you when you return to a website you visited before. This category of leaks can be prevented by browser if they clean or isolate data between browser sessions. (In cases where a user has logged into a website or entered detailed information, it may be justifiable for a browser to retain information across sessions. These tests check when no such justification exists: when you have entered no significant information into a website, will the browser still retain data that allows you to be tracked across sessions?) | |||||||||
Alt-Svc
Alt-Svc allows the server to indicate to the web browser that a resource should be loaded on a different server. Because this is a persistent setting, it could be used to track users across websites if it is not correctly partitioned. | write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h2 unsupported: false passed: true test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h2 result, different session: h3 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h2 result, different session: h2 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: 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. | write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: 8dcf3049-0641-4832-bc66-2373dea8b2ff_1p result, different session: Error: undefined is not an object (evaluating 'cacheKeys[0].url') unsupported: false passed: true test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: eb0dda01-983e-40e8-b21b-217f51793243_1p result, different session: eb0dda01-983e-40e8-b21b-217f51793243_1p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: Error: Failed reading data from the file system result, different session: Error: Failed reading data from the file system unsupported: true passed: undefined test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: Error: The operation is insecure. result, different session: Error: The operation is insecure. unsupported: true passed: undefined test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p unsupported: false passed: false test failed: 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. | write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p_http result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p_http result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: 8dcf3049-0641-4832-bc66-2373dea8b2ff_1p_http result, different session: 8dcf3049-0641-4832-bc66-2373dea8b2ff_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p_http result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: eb0dda01-983e-40e8-b21b-217f51793243_1p_http result, different session: eb0dda01-983e-40e8-b21b-217f51793243_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p_http result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: e54f56ee-527d-4b84-847f-9120b105376f_1p_http result, different session: e54f56ee-527d-4b84-847f-9120b105376f_1p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: 80df2b1d-cc96-4f9a-8af8-418737aa9557_1p_http result, different session: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p_http result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p_http unsupported: false passed: false test failed: false |
cookie (JS)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them. | write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p_js result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p_js result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: 8dcf3049-0641-4832-bc66-2373dea8b2ff_1p_js result, different session: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p_js result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: eb0dda01-983e-40e8-b21b-217f51793243_1p_js result, different session: eb0dda01-983e-40e8-b21b-217f51793243_1p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p_js result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: e54f56ee-527d-4b84-847f-9120b105376f_1p_js result, different session: e54f56ee-527d-4b84-847f-9120b105376f_1p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: 80df2b1d-cc96-4f9a-8af8-418737aa9557_1p_js result, different session: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p_js result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p_js unsupported: false passed: false test failed: false |
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers. | 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: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p unsupported: false passed: false test failed: false |
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: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p unsupported: false passed: false test failed: false |
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites. | write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_7874627047609934 result, different session: fake_7874627047609934 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_46435514990582627 result, different session: fake_46435514990582627 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_05074008774456429 result, different session: fake_05074008774456429 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_44795063423598 result, different session: fake_44795063423598 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_5444769045116449 result, different session: fake_5444769045116449 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_07743221482212781 result, different session: fake_07743221482212781 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_1617914929183284 result, different session: fake_1617914929183284 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_05217536698321945 result, different session: fake_688707112546648 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_25904896503836516 result, different session: fake_25904896503836516 unsupported: false passed: false test failed: 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. | write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: Error: Failed to fetch result, different session: 1 unsupported: true passed: undefined test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 2 result, different session: 2 unsupported: false passed: false test failed: 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. | write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking. | write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: Error: Failed to fetch result, different session: 1 unsupported: true passed: undefined test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: Error: Failed to fetch result, different session: 1 unsupported: true passed: undefined test failed: 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. | write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: 8dcf3049-0641-4832-bc66-2373dea8b2ff_1p result, different session: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: eb0dda01-983e-40e8-b21b-217f51793243_1p result, different session: eb0dda01-983e-40e8-b21b-217f51793243_1p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: e54f56ee-527d-4b84-847f-9120b105376f_1p result, different session: e54f56ee-527d-4b84-847f-9120b105376f_1p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: 80df2b1d-cc96-4f9a-8af8-418737aa9557_1p result, different session: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p unsupported: false passed: false test failed: 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. | write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_1p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_1p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: 8dcf3049-0641-4832-bc66-2373dea8b2ff_1p result, different session: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_1p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: eb0dda01-983e-40e8-b21b-217f51793243_1p result, different session: eb0dda01-983e-40e8-b21b-217f51793243_1p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_1p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: e54f56ee-527d-4b84-847f-9120b105376f_1p result, different session: e54f56ee-527d-4b84-847f-9120b105376f_1p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: 80df2b1d-cc96-4f9a-8af8-418737aa9557_1p result, different session: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_1p unsupported: false passed: false test failed: 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. | write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h2 result, different session: h3 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h2 result, different session: h3 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h2 result, different session: h2 unsupported: true passed: undefined test failed: false |
write: async () => { // Clear Alt-Svc caching first. let responseText = ""; for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/clear"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after clear:", responseText); // Store "h3" state in Alt-Svc cache for (let i = 0; i < 3; ++i) { await fetch(altSvcOrigin + "/set"); await sleepMs(100); } responseText = await fetchText(altSvcOrigin + "/protocol"); console.log("after set:", responseText); } read: async () => { const protocol = await fetchText(altSvcOrigin + "/protocol"); if ((new URL(location)).searchParams.get("thirdparty") === "same") { if (protocol !== "h3") { throw new Error("Unsupported"); } } return protocol; } result, same session: h3 result, different session: h3 unsupported: false passed: false test failed: 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. | write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: Error: undefined is not an object (evaluating 'cacheKeys[0].url') result, different session: Error: undefined is not an object (evaluating 'cacheKeys[0].url') unsupported: true passed: undefined test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: eb0dda01-983e-40e8-b21b-217f51793243_3p result, different session: eb0dda01-983e-40e8-b21b-217f51793243_3p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: c29ade6f-6e91-4000-9582-ca243d4f2894_3p result, different session: c29ade6f-6e91-4000-9582-ca243d4f2894_3p unsupported: false passed: false test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: Error: The operation is insecure. result, different session: Error: The operation is insecure. unsupported: true passed: undefined test failed: false |
write: async (key) => { try { let cache = await caches.open("supercookies"); cache.addAll([`test.css?key=${key}`]); } catch (e) { throw new Error("Unsupported"); } } read: async () => { let cache = await caches.open("supercookies"); let cacheKeys = await cache.keys(); let url = cacheKeys[0].url; return (new URL(url)).searchParams.get("key"); } result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p unsupported: false passed: false test failed: false |
cookie (HTTP)
The cookie, first introduced by Netscape in 1994, is a small amount of data stored by your browser on a website's behalf. It has legitimate uses, but it is also the classic cross-site tracking mechanism, and today still the most popular method of tracking users across websites. Browsers can stop cookies from being used for cross-site tracking by either blocking or partitioning them. | write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p_http result, different session: null unsupported: false passed: true test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p_http result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p_http result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: eb0dda01-983e-40e8-b21b-217f51793243_3p_http result, different session: eb0dda01-983e-40e8-b21b-217f51793243_3p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p_http result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p_http unsupported: false passed: false test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
write: async (secret) => { // Request a page that will send an HTTPOnly 'set-cookie' response header with secret value. await fetch(`${baseURI}cookie?secret=${secret}_http`); } read: async () => { // Test if we now send a requests with a 'cookie' header containing the secret. let response = await fetch(`${baseURI}headers`); let cookie = (await response.json())["cookie"]; return cookie ? cookie.match(/secret=([\w-]+)/)[1]: null; } result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p_http result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p_http unsupported: false passed: false test failed: 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. | write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p_js result, different session: null unsupported: false passed: true test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p_js result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p_js result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: eb0dda01-983e-40e8-b21b-217f51793243_3p_js result, different session: eb0dda01-983e-40e8-b21b-217f51793243_3p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p_js result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p_js unsupported: false passed: false test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
write: (secret) => { document.cookie = `secret=${secret}_js; max-age=3600; SameSite=None; Secure`; } read: () => document.cookie ? document.cookie.match(/secret=([\w-]+)/)[1] : null result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
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: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p_js result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p_js unsupported: false passed: false test failed: false |
CookieStore
The Cookie Store API is an alternative asynchronous API for managing cookies, supported by some browsers. | 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: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p result, different session: null unsupported: false passed: true test failed: false |
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: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p unsupported: false passed: false test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
write: (data) => { const msPerHour = 60 * 60 * 1000; if (!window.cookieStore) { throw new Error("Unsupported"); } window.cookieStore.set({ name: "partition_test", value: data, expires: Date.now() + msPerHour, sameSite: "none" }); } read: async () => { if (!window.cookieStore) { throw new Error("Unsupported"); } const cookie = await window.cookieStore.get("partition_test"); if (!cookie) { return null; } return cookie.value; } result, same session: Error: Unsupported result, different session: Error: Unsupported unsupported: true passed: undefined test failed: false |
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: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p unsupported: false passed: false test failed: false |
CSS cache
CSS stylesheets are cached, and if that cache is shared between websites, it can be used to track users across sites. | write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_5670925018311572 result, different session: fake_5670925018311572 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_4150730120744297 result, different session: fake_4150730120744297 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_7429052136396279 result, different session: fake_7429052136396279 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_7221522415872998 result, different session: fake_7221522415872998 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_8170554612828678 result, different session: fake_8170554612828678 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_5966791259768218 result, different session: fake_5966791259768218 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_9475647907685694 result, different session: fake_9475647907685694 unsupported: false passed: false test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_9497429960602763 result, different session: fake_6845812176349395 unsupported: false passed: true test failed: false |
write: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return key; } read: async (key) => { const href = testURI("resource", "css", key); const head = document.getElementsByTagName("head")[0]; head.innerHTML += `<link type="text/css" rel="stylesheet" href="${href}">`; const testElement = document.querySelector("#css"); let fontFamily; while (true) { await sleepMs(100); fontFamily = getComputedStyle(testElement).fontFamily; if (fontFamily.startsWith("fake")) { break; } } console.log(fontFamily); return fontFamily; } result, same session: fake_8482089041296716 result, different session: fake_8482089041296716 unsupported: false passed: false test failed: 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. | write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => key read: async (key) => { // Wait for the favicon to load (defined in supercookies.html) await sleepMs(2000); let response = await fetch( testURI("ctr", "favicon", key), {"cache": "reload"}); let count = (await response.text()).trim(); if (count === "0") { throw new Error("No requests received"); } return count; } result, same session: 2 result, different session: 2 unsupported: false passed: false test failed: 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. | write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); return key; } read: async (key) => { let response = await fetch(testURI("resource", "fetch", key), {cache: "force-cache"}); let countResponse = await fetch(testURI("ctr", "fetch", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
font cache
Web fonts are sometimes stored in their own cache, which is vulnerable to being abused for cross-site tracking. | write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 2 result, different session: 2 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: async (key) => { let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } body { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); return key; } read: async (key) => { const text = document.createElement("span"); text.id = "text"; text.innerText = "test"; document.body.appendChild(text); const originalWidth = text.getBoundingClientRect().width; let style = document.createElement("style"); style.type='text/css'; let fontURI = testURI("resource", "font", key); style.innerHTML = `@font-face {font-family: "myFont"; src: url("${fontURI}"); } #text { font-family: "myFont" }`; document.getElementsByTagName("head")[0].appendChild(style); let newWidth; do { await sleepMs(100); newWidth = text.getBoundingClientRect().width; } while (newWidth < 0 || newWidth === originalWidth) let response = await fetch( testURI("ctr", "font", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); iframe.addEventListener("load", () => resolve(key), {once: true}); iframe.src = testURI("resource", "page", key); }) read: async (key) => { let iframe = document.createElement("iframe"); document.body.appendChild(iframe); let iframeLoadPromise = new Promise((resolve, reject) => { iframe.addEventListener("load", resolve, {once: true}); }); let address = testURI("resource", "page", key); iframe.src = address; await iframeLoadPromise; let response = await fetch( testURI("ctr", "page", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let img = document.createElement("img"); document.body.appendChild(img); img.addEventListener("load", () => resolve(key), {once: true}); img.src = testURI("resource", "image", key); }) read: async (key) => { let img = document.createElement("img"); document.body.appendChild(img); let imgLoadPromise = new Promise((resolve, reject) => { img.addEventListener("load", resolve, {once: true}); }); img.src = testURI("resource", "image", key); await imgLoadPromise; let response = await fetch( testURI("ctr", "image", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: undefined result, different session: undefined unsupported: true passed: undefined test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: eb0dda01-983e-40e8-b21b-217f51793243_3p result, different session: eb0dda01-983e-40e8-b21b-217f51793243_3p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p unsupported: false passed: false test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: e54f56ee-527d-4b84-847f-9120b105376f_3p result, different session: undefined unsupported: false passed: true test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: Error: The operation is insecure. result, different session: Error: The operation is insecure. unsupported: true passed: undefined test failed: false |
write: async (secret) => { try { return await IdbKeyVal.set("secret", secret); } catch (e) { throw new Error("Unsupported"); } } read: () => IdbKeyVal.get("secret") result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p unsupported: false passed: false test failed: 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. | write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p result, different session: f7e729f7-9e22-4b1b-baa7-038cdd2b7466_3p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p result, different session: eac80989-abd5-4d75-ab7d-bc4b3f378167_3p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: null result, different session: null unsupported: true passed: undefined test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p result, different session: 25ffccc7-68bd-4d2f-86e0-8a0bb87be277_3p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: eb0dda01-983e-40e8-b21b-217f51793243_3p result, different session: eb0dda01-983e-40e8-b21b-217f51793243_3p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p result, different session: e91cf262-3db2-4ce2-9312-b912493f0ef0_3p unsupported: false passed: false test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: e54f56ee-527d-4b84-847f-9120b105376f_3p result, different session: null unsupported: false passed: true test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: Error: The operation is insecure. result, different session: Error: The operation is insecure. unsupported: true passed: undefined test failed: false |
write: (secret) => localStorage.setItem("secret", secret) read: () => localStorage.getItem("secret") result, same session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p result, different session: 5c4b21b3-6581-43d2-8006-dc5d38ff986b_3p unsupported: false passed: false test failed: 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. | write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: Error: No requests received result, different session: Error: No requests received unsupported: true passed: undefined test failed: false |
write: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); return key; } read: async (key) => { let link = document.createElement("link"); link.rel = "prefetch"; link.href = testURI("resource", "prefetch", key); document.getElementsByTagName("head")[0].appendChild(link); await sleepMs(500); let response = await fetch( testURI("ctr", "prefetch", key), {"cache": "reload"}); let countString = (await response.text()).trim(); if (parseInt(countString) === 0) { throw new Error("No requests received"); } return countString; } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: (key) => new Promise((resolve, reject) => { let script = document.createElement("script"); document.body.appendChild(script); script.addEventListener("load", () => resolve(key), {once: true}); script.src = testURI("resource", "script", key); }) read: async (key) => { let script = document.createElement("script"); document.body.appendChild(script); let scriptLoadPromise = new Promise((resolve, reject) => { script.addEventListener("load", resolve, {once: true}); }); script.src = testURI("resource", "script", key); await scriptLoadPromise; let response = await fetch( testURI("ctr", "script", key), {"cache": "reload"}); return (await response.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: 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. | write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 2 unsupported: false passed: true test failed: false |
write: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; return key; } read: async (key) => { const req = new XMLHttpRequest(); const loadPromise = new Promise(resolve => req.addEventListener("load", resolve)); req.open("GET", testURI("resource", "xhr", key)); req.send(); await loadPromise; let countResponse = await fetch(testURI("ctr", "xhr", key), {cache: "reload"}); return (await countResponse.text()).trim(); } result, same session: 1 result, different session: 1 unsupported: false passed: false test failed: false |
DNS privacy testsWhich browsers keep their DNS queries encrypted?
The Domain Name System (DNS) is the method by which web browsers look up the IP address for each website you visit. In a DNS query, a web browser will ask a DNS resolver (somewhere on the internet) for the IP address corresponding to a domain name (such as nytimes.com) for a website you want to visit. Traditionally, most web browsers have sent their DNS queries unencrypted, which means your ISP or anyone else on the network between your computer and the DNS resolver can eavesdrop on the websites you visit. In recent years, web browsers and operating systems have begun to introduce encrypted DNS, including the DNS over HTTPS (DoH) protocol, to encrypt the DNS request from your browser and the response from the resolver to keep your browsing history from leaking. These tests check whether a browser is still protecting its DNS requests by sending them encrypted. | |||||||||
Location: Brazil
Checks whether the browser decides to use encrypted DNS if the computer is located in Brazil. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
Location: China
Checks whether the browser decides to use encrypted DNS if the computer is located in China. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
Location: Germany
Checks whether the browser decides to use encrypted DNS if the computer is located in Germany. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
Location: India
Checks whether the browser decides to use encrypted DNS if the computer is located in India. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
Location: Nigeria
Checks whether the browser decides to use encrypted DNS if the computer is located in Nigeria. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
Location: Russia
Checks whether the browser decides to use encrypted DNS if the computer is located in Russia. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
Location: United States
Checks whether the browser decides to use encrypted DNS if the computer is located in United States. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
OS DNS: Cloudflare
Checks whether the browser decides to use encrypted DNS if the operating system's default DNS provider is Cloudflare. | passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
passed: false leak detected: true |
passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
OS DNS: Comodo
Checks whether the browser decides to use encrypted DNS if the operating system's default DNS provider is Comodo. | passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
OS DNS: Google
Checks whether the browser decides to use encrypted DNS if the operating system's default DNS provider is Google. | passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
passed: false leak detected: true |
passed: true leak detected: false |
passed: true leak detected: false |
passed: true leak detected: false |
OS DNS: Quad9
Checks whether the browser decides to use encrypted DNS if the operating system's default DNS provider is Quad9. | passed: false leak detected: true |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
passed: true leak detected: false |
passed: false leak detected: true |
passed: true leak detected: false |
passed: true leak detected: false |
passed: false leak detected: true |