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CSS3 Text-shadow

- CR

Method of applying one or more shadow or blur effects to text

IE

  1. 5.5 - 9: Not supported
  2. 10: Supported
  3. 11: Supported

Edge

  1. 12 - 18: Supported
  2. 79 - 87: Supported
  3. 88: Supported

Firefox

  1. 2 - 3: Not supported
  2. 3.5 - 84: Supported
  3. 85: Supported
  4. 86 - 87: Supported

Chrome

  1. 4 - 87: Supported
  2. 88: Supported
  3. 89 - 91: Supported

Safari

  1. 3.1 - 3.2: Partial support
  2. 4 - 13.1: Supported
  3. 14: Supported
  4. TP: Supported

Opera

  1. 9: Not supported
  2. 9.5 - 72: Supported
  3. 73: Supported

iOS Safari

  1. 3.2 - 13.7: Supported
  2. 14: Supported

Opera Mini

  1. all: Partial support

Android Browser

  1. 2.1 - 4.4.4: Supported
  2. 81: Supported

Opera Mobile

  1. 10 - 12.1: Supported
  2. 59: Supported

Chrome for Android

  1. 88: Supported

Firefox for Android

  1. 85: 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

Opera Mini ignores the blur-radius set, so no blur effect is visible. Text-shadow behavior can be somewhat emulated in older IE versions using the non-standard "dropshadow" or "glow" filters.

Resources:
Mozilla hacks article
Live editor
WebPlatform Docs