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Case-insensitive CSS attribute selectors

- WD

Including an i before the ] in a CSS attribute selector causes the attribute value to be matched in an ASCII-case-insensitive manner. For example, [b="xyz" i] would match both <a b="xyz"> and <a b="XYZ">.

Chrome

  1. ❌ 4 - 48: Not supported
  2. ✅ 49 - 135: Supported
  3. ✅ 136: Supported
  4. ✅ 137 - 139: Supported

Edge

  1. ❌ 12 - 18: Not supported
  2. ✅ 79 - 135: Supported
  3. ✅ 136: Supported

Safari

  1. ❌ 3.1 - 8: Not supported
  2. ✅ 9 - 18.4: Supported
  3. ✅ 18.5: Supported
  4. ✅ TP: Supported

Firefox

  1. ❌ 2 - 46: Not supported
  2. ✅ 47 - 137: Supported
  3. ✅ 138: Supported
  4. ✅ 139 - 141: Supported

Opera

  1. ❌ 9 - 35: Not supported
  2. ✅ 36 - 116: Supported
  3. ✅ 117: Supported

IE

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

Chrome for Android

  1. ✅ 136: Supported

Safari on iOS

  1. ❌ 3.2 - 8.4: Not supported
  2. ✅ 9 - 18.4: Supported
  3. ✅ 18.5: Supported

Samsung Internet

  1. ❌ 4: Not supported
  2. ✅ 5 - 26: Supported
  3. ✅ 27: 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. ✅ 136: Supported

Firefox for Android

  1. ✅ 137: 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 - CSS case-insensitive
JS Bin testcase