{
  "schema_version": "1.1",
  "id": "firefox-total-cookie-protection-by-default",
  "slug": "firefox-total-cookie-protection-by-default",
  "url": "https://groundedkit.com/claims/firefox-total-cookie-protection-by-default/",
  "api_url": "https://groundedkit.com/api/claims/firefox-total-cookie-protection-by-default.json",
  "claim": "Firefox isolates cookies per website by default (Total Cookie Protection), rolled out by default to users worldwide starting June 2022",
  "commonly_cited_as": "\"Firefox blocks third-party cookies\"",
  "verdict": "verified",
  "verdict_definition": "Primary source found; it says the same thing, the scope matches, and it is reasonably current.",
  "confidence": "high",
  "rating": {
    "value": 5,
    "best": 5,
    "worst": 1
  },
  "origin": {
    "publisher": "Mozilla",
    "title": "Firefox rolls out Total Cookie Protection by default to more users worldwide",
    "year": "2022 (updated Aug. 2024)"
  },
  "quote": "Total Cookie Protection works by creating a separate “cookie jar” for each website you visit.",
  "method": "Mozilla product announcement.",
  "drift": [
    "Cookies are partitioned per site rather than blocked outright"
  ],
  "interest": "Mozilla describing its own browser.",
  "safe_rephrasing": "Since 2022 Firefox has, by default, kept each site's cookies in a separate 'cookie jar', so trackers cannot follow users across sites.",
  "sources": [
    {
      "title": "Mozilla Blog — Total Cookie Protection by default",
      "url": "https://blog.mozilla.org/en/products/firefox/firefox-rolls-out-total-cookie-protection-by-default-to-all-users-worldwide/",
      "primary": true
    }
  ],
  "kind": "reference_fact",
  "as_of": "Mozilla blog, June 14, 2022",
  "last_checked": "2026-10-17",
  "stale": false,
  "date_reviewed": "2026-10-17",
  "license": "CC BY 4.0",
  "license_url": "https://creativecommons.org/licenses/by/4.0/"
}