Can I use
?

XHTML+SMIL animation

- UNOFF

Method of using SMIL animation in web pages

Chrome

  1. ❌ 4 - 149: Not supported (but has polyfill available)
  2. ❌ 150: Not supported (but has polyfill available)
  3. ❌ 151 - 153: Not supported (but has polyfill available)

Edge

  1. ❌ 12 - 18: Not supported
  2. ❌ 79 - 149: Not supported (but has polyfill available)
  3. ❌ 150: Not supported (but has polyfill available)

Safari

  1. ❌ 3.1 - 26.3: Not supported (but has polyfill available)
  2. ❌ 26.4: Not supported (but has polyfill available)
  3. ❌ 26.5 - TP: Not supported (but has polyfill available)

Firefox

  1. ❌ 2 - 151: Not supported (but has polyfill available)
  2. ❌ 152: Not supported (but has polyfill available)
  3. ❌ 153 - 155: Not supported (but has polyfill available)

Opera

  1. ❌ 9 - 127: Not supported (but has polyfill available)
  2. ❌ 131: Not supported (but has polyfill available)

IE

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

Chrome for Android

  1. ❌ 150: Not supported (but has polyfill available)

Safari on iOS

  1. ❌ 3.2 - 26.3: Not supported (but has polyfill available)
  2. ❌ 26.4: Not supported (but has polyfill available)
  3. ❌ 26.5: Not supported (but has polyfill available)

Samsung Internet

  1. ❌ 4 - 29: Not supported (but has polyfill available)
  2. ❌ 30: Not supported (but has polyfill available)

Opera Mini

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

Opera Mobile

  1. ❌ 10 - 12.1: Not supported (but has polyfill available)
  2. ❌ 80: Not supported (but has polyfill available)

UC Browser for Android

  1. ❌ 15.5: Not supported (but has polyfill available)

Android Browser

  1. ❌ 2.1 - 4.4.4: Not supported (but has polyfill available)
  2. ❌ 150: Not supported (but has polyfill available)

Firefox for Android

  1. ❌ 152: Not supported (but has polyfill available)

QQ Browser

  1. ❌ 14.9: Not supported (but has polyfill available)

Baidu Browser

  1. ❌ 13.52: Not supported (but has polyfill available)

KaiOS Browser

  1. ❌ 2.5: Not supported (but has polyfill available)
  2. ❌ 3: Not supported (but has polyfill available)

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

Resources:
Wikipedia
JS library to support XHTML+SMIL