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 - 90: Supported
  3. 91: Supported

Firefox

  1. 2 - 3: Not supported
  2. 3.5 - 88: Supported
  3. 89: Supported
  4. 90 - 91: Supported

Chrome

  1. 4 - 90: Supported
  2. 91: Supported
  3. 92 - 94: Supported

Safari

  1. 3.1 - 3.2: Partial support
  2. 4 - 14: Supported
  3. 14.1: Supported
  4. 15 - TP: Supported

Opera

  1. 9: Not supported
  2. 9.5 - 75: Supported
  3. 76: Supported

Safari on iOS

  1. 3.2 - 14.4: Supported
  2. 14.5: Supported

Opera Mini

  1. all: Partial support

Android Browser

  1. 2.1 - 4.4.4: Supported
  2. 91: Supported

Opera Mobile

  1. 10 - 12.1: Supported
  2. 62: Supported

Chrome for Android

  1. 91: Supported

Firefox for Android

  1. 89: Supported

UC Browser for Android

  1. 12.12: Supported

Samsung Internet

  1. 4 - 13.0: Supported
  2. 14.0: 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