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Content Security Policy Level 2

- REC

Mitigate cross-site scripting attacks by only allowing certain sources of script, style, and other resources. CSP 2 adds hash-source, nonce-source, and five new directives

Chrome

  1. ❌ 4 - 35: Not supported
  2. ◐ 36 - 38: Partial support
  3. ◐ 39: Partial support
  4. ✅ 40 - 137: Supported
  5. ✅ 138: Supported
  6. ✅ 139 - 141: Supported

Edge

  1. ❌ 12 - 14: Not supported
  2. ◐ 15 - 18: Partial support
  3. ✅ 79 - 137: Supported
  4. ✅ 138: Supported

Safari

  1. ❌ 3.1 - 9.1: Not supported
  2. ✅ 10 - 18.4: Supported
  3. ✅ 18.5: Supported
  4. ✅ 26.0 - TP: Supported

Firefox

  1. ❌ 2 - 30: Not supported
  2. ◐ 31 - 34: Partial support
  3. ◐ 35: Partial support
  4. ◐ 36 - 44: Partial support
  5. ✅ 45 - 139: Supported
  6. ✅ 140: Supported
  7. ✅ 141 - 143: Supported

Opera

  1. ❌ 9 - 22: Not supported
  2. ◐ 23 - 25: Partial support
  3. ◐ 26: Partial support
  4. ✅ 27 - 116: Supported
  5. ✅ 117: Supported

IE

  1. ❌ 5.5 - 10: Not supported
  2. ❌ 11: Not supported

Chrome for Android

  1. ✅ 138: Supported

Safari on iOS

  1. ❌ 3.2 - 9.3: Not supported
  2. ✅ 10 - 18.4: Supported
  3. ✅ 18.5: Supported
  4. ✅ 26.0: Supported

Samsung Internet

  1. ✅ 4 - 27: Supported
  2. ✅ 28: Supported

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

  1. ❌ 10 - 12.1: Not supported
  2. ✅ 80: Supported

UC Browser for Android

  1. ✅ 15.5: Supported

Android Browser

  1. ❌ 2.1 - 4.4.4: Not supported
  2. ✅ 138: Supported

Firefox for Android

  1. ✅ 140: Supported

QQ Browser

  1. ✅ 14.9: Supported

Baidu Browser

  1. ✅ 13.52: Supported

KaiOS Browser

  1. ✅ 2.5: Supported
  2. ✅ 3: Supported
Resources:
MDN Web Docs - Content Security Policy
HTML5Rocks article