Can I use
?

Lazy loading via attribute for video & audio

- LS

The loading attribute on video & audio elements gives authors control over when the browser should start loading the media resource, allowing deferred loading until the element is near the viewport.

Chrome

  1. ❌ 4 - 146: Not supported
  2. ❌ 147: Disabled by default
  3. ✅ 148 - 150: Supported

Edge

  1. ❌ 12 - 145: Not supported
  2. ❌ 146: Not supported

Safari

  1. ❌ 3.1 - 26.3: Not supported
  2. ❌ 26.4: Not supported
  3. ❌ 26.5 - TP: Not supported

Firefox

  1. ❌ 2 - 148: Not supported
  2. ❌ 149: Not supported
  3. ❌ 150 - 152: Not supported

Opera

  1. ❌ 9 - 126: Not supported
  2. ❌ 127: Not supported

IE

  1. ❌ 5.5 - 10: Not supported
  2. ❌ 11: Not supported

Chrome for Android

  1. ❌ 147: Not supported

Safari on iOS

  1. ❌ 3.2 - 26.3: Not supported
  2. ❌ 26.4: Not supported
  3. ❌ 26.5: Not supported

Samsung Internet

  1. ❌ 4 - 28: Not supported
  2. ❌ 29: Not supported

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

  1. ❌ 10 - 12.1: Not supported
  2. ❌ 80: Not supported

UC Browser for Android

  1. ❌ 15.5: Not supported

Android Browser

  1. ❌ 2.1 - 4.4.4: Not supported
  2. ❌ 147: Not supported

Firefox for Android

  1. ❌ 149: Not supported

QQ Browser

  1. ❌ 14.9: Not supported

Baidu Browser

  1. ❌ 13.52: Not supported

KaiOS Browser

  1. ❌ 2.5: Not supported
  2. ❌ 3: Not supported
Resources:
Firefox support bug
Mozilla Standards Position (positive)
WebKit Standards Position (positive)
WHATWG HTML spec PR
Chromium Intent to Ship
Blog post by Scott Jehl