Autofocus attribute

- LS

Allows a form field to be immediately focused on page load.

IE

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

Edge

  1. 12 - 91: Supported
  2. 92: Supported

Firefox

  1. 2 - 3.6: Not supported
  2. 4 - 89: Supported
  3. 90: Supported
  4. 91 - 92: Supported

Chrome

  1. 4: Not supported
  2. 5 - 91: Supported
  3. 92: Supported
  4. 93 - 95: Supported

Safari

  1. 3.1 - 4: Not supported
  2. 5 - 14: Supported
  3. 14.1: Supported
  4. 15 - TP: Supported

Opera

  1. 9: Not supported
  2. 9.5 - 76: Supported
  3. 77: Supported

Safari on iOS

  1. 3.2 - 14.4: Not supported
  2. 14.5: Not supported

Opera Mini

  1. all: Not supported

Android Browser

  1. 2.1 - 2.3: Not supported
  2. 3 - 4.4.4: Supported
  3. 92: Supported

Opera Mobile

  1. 10 - 12.1: Not supported
  2. 64: Supported

Chrome for Android

  1. 92: Supported

Firefox for Android

  1. 90: Supported

UC Browser for Android

  1. 12.12: Not 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: Not supported

While not supported in iOS Safari, it does work in iOS WebViews.

Resources:
Article on autofocus
MDN Web Docs - autofocus attribute