XHTML+SMIL animation

- UNOFF

Method of using SMIL animation in web pages

IE

  1. 5.5: Not supported
  2. 6 - 8: Partial support
  3. 9 - 10: Not supported
  4. 11: Not supported

Edge

  1. 12 - 18: Not supported
  2. 79 - 91: Not supported (but has polyfill available)
  3. 92: Not supported (but has polyfill available)

Firefox

  1. 2 - 89: Not supported (but has polyfill available)
  2. 90: Not supported (but has polyfill available)
  3. 91 - 92: Not supported (but has polyfill available)

Chrome

  1. 4 - 91: Not supported (but has polyfill available)
  2. 92: Not supported (but has polyfill available)
  3. 93 - 95: Not supported (but has polyfill available)

Safari

  1. 3.1 - 14: Not supported (but has polyfill available)
  2. 14.1: Not supported (but has polyfill available)
  3. 15 - TP: Not supported (but has polyfill available)

Opera

  1. 9 - 76: Not supported (but has polyfill available)
  2. 77: Not supported (but has polyfill available)

Safari on iOS

  1. 3.2 - 14.4: Not supported (but has polyfill available)
  2. 14.5: Not supported (but has polyfill available)

Opera Mini

  1. all: Not supported (but has polyfill available)

Android Browser

  1. 2.1 - 4.4.4: Not supported (but has polyfill available)
  2. 92: Not supported (but has polyfill available)

Opera Mobile

  1. 10 - 12.1: Not supported (but has polyfill available)
  2. 64: Not supported (but has polyfill available)

Chrome for Android

  1. 92: Not supported (but has polyfill available)

Firefox for Android

  1. 90: Not supported (but has polyfill available)

UC Browser for Android

  1. 12.12: Not supported (but has polyfill available)

Samsung Internet

  1. 4 - 13.0: Not supported (but has polyfill available)
  2. 14.0: Not supported (but has polyfill available)

QQ Browser

  1. 10.4: Not supported (but has polyfill available)

Baidu Browser

  1. 7.12: Not supported (but has polyfill available)

KaiOS Browser

  1. 2.5: Not supported (but has polyfill available)

Internet Explorer supports the W3C proposal HTML+TIME, which is largely the same as XHTML+SMIL

Resources:
JS library to support XHTML+SMIL
Wikipedia