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CSS initial value

- CR

A CSS value that will apply a property's initial value as defined in the CSS specification that defines the property

IE

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

Edge

  1. 12 - 86: Supported
  2. 87: Supported

Firefox

  1. 2 - 3: Partial support
  2. 3.5 - 18: Supported
  3. 19 - 83: Supported
  4. 84: Supported
  5. 85 - 86: Supported

Chrome

  1. 4 - 86: Supported
  2. 87: Supported
  3. 88 - 90: Supported

Safari

  1. 3.1: Support unknown
  2. 3.2 - 13.1: Supported
  3. 14: Supported
  4. TP: Supported

Opera

  1. 9 - 12.1: Not supported
  2. 15 - 71: Supported
  3. 72: Supported

iOS Safari

  1. 3.2: Support unknown
  2. 4 - 13.7: Supported
  3. 14: Supported

Opera Mini

  1. all: Not supported

Android Browser

  1. 2.1 - 2.2: Support unknown
  2. 2.3 - 4.4.4: Supported
  3. 81: Supported

Opera Mobile

  1. 10 - 12.1: Not supported
  2. 59: Supported

Chrome for Android

  1. 87: Supported

Firefox for Android

  1. 83: Supported

UC Browser for Android

  1. 12.12: Supported

Samsung Internet

  1. 4 - 12.0: Supported
  2. 13.0: Supported

QQ Browser

  1. 10.4: Supported

Baidu Browser

  1. 7.12: Supported

KaiOS Browser

  1. 2.5: Supported
Resources:
CSS Tricks article
MDN Web Docs - CSS initial