Can I use
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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 - 107: Supported
  3. 108: Supported
  4. 109 - 111: Supported

Edge

  1. 12 - 18: Not supported
  2. 79 - 107: Supported
  3. 108: Supported

Safari

  1. 3.1 - 8: Not supported
  2. 9 - 16.1: Supported
  3. 16.2: Supported
  4. 16.3 - TP: Supported

Firefox

  1. 2 - 46: Not supported
  2. 47 - 106: Supported
  3. 107: Supported
  4. 108 - 109: Supported

Opera

  1. 9 - 35: Not supported
  2. 36 - 91: Supported
  3. 92: Supported

IE

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

Chrome for Android

  1. 108: Supported

Safari on iOS

  1. 3.2 - 8.4: Not supported
  2. 9 - 16.1: Supported
  3. 16.2: Supported
  4. 16.3: Supported

Samsung Internet

  1. 4: Not supported
  2. 5 - 18.0: Supported
  3. 19.0: Supported

Opera Mini

  1. all: Not supported

Opera Mobile

  1. 10 - 12.1: Not supported
  2. 72: Supported

UC Browser for Android

  1. 13.4: Supported

Android Browser

  1. 2.1 - 4.4.4: Not supported
  2. 108: Supported

Firefox for Android

  1. 107: Supported

QQ Browser

  1. 13.1: Supported

Baidu Browser

  1. 13.18: Supported

KaiOS Browser

  1. 2.5: Supported
Resources:
MDN Web Docs - CSS case-insensitive
JS Bin testcase