Can I use
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classList (DOMTokenList)

- LS

Method of easily manipulating classes on elements, using the DOMTokenList object.

Chrome

  1. 4 - 7: Not supported (but has polyfill available)
  2. 8 - 22: Partial support
  3. 23: Partial support
  4. 24 - 27: Partial support
  5. 28 - 123: Supported
  6. 124: Supported
  7. 125 - 127: Supported

Edge

  1. 12 - 122: Supported
  2. 123: Supported

Safari

  1. 3.1 - 5: Not supported (but has polyfill available)
  2. 5.1 - 6.1: Partial support
  3. 7 - 17.3: Supported
  4. 17.4: Supported
  5. 17.5 - TP: Supported

Firefox

  1. 2 - 3.5: Not supported (but has polyfill available)
  2. 3.6 - 23: Partial support
  3. 24 - 25: Partial support
  4. 26 - 124: Supported
  5. 125: Supported
  6. 126 - 128: Supported

Opera

  1. 9 - 11.1: Not supported (but has polyfill available)
  2. 11.5 - 12.1: Partial support
  3. 15 - 108: Supported
  4. 109: Supported

IE

  1. 5.5 - 9: Not supported (but has polyfill available)
  2. 10: Partial support
  3. 11: Partial support

Chrome for Android

  1. 123: Supported

Safari on iOS

  1. 3.2 - 4.3: Not supported (but has polyfill available)
  2. 5 - 6.1: Partial support
  3. 7 - 17.3: Supported
  4. 17.4: Supported
  5. 17.5: Supported

Samsung Internet

  1. 4 - 23: Supported
  2. 24: Supported

Opera Mini

  1. all: Partial support

Opera Mobile

  1. 10 - 11: Not supported (but has polyfill available)
  2. 11.1 - 12.1: Partial support
  3. 80: Supported

UC Browser for Android

  1. 15.5: Supported

Android Browser

  1. 2.1 - 2.3: Not supported (but has polyfill available)
  2. 3 - 4.3: Partial support
  3. 4.4 - 4.4.4: Supported
  4. 123: Supported

Firefox for Android

  1. 124: Supported

QQ Browser

  1. 14.9: Supported

Baidu Browser

  1. 13.52: Supported

KaiOS Browser

  1. 2.5: Supported
  2. 3: Supported
Resources:
MDN Web Docs - Element.classList
Polyfill script
Mozilla Hacks article
WebPlatform Docs
Demo using classList
SitePoint article