Can I use
?

WebAssembly Threads and Atomics

- WD

An extension to WebAssembly adding shared memory and atomic memory operations

Chrome

  1. ❌ 4 - 73: Not supported
  2. ✅ 74 - 127: Supported
  3. ✅ 128: Supported
  4. ✅ 129 - 131: Supported

Edge

  1. ❌ 12 - 18: Not supported
  2. ✅ 79 - 127: Supported
  3. ✅ 128: Supported

Safari

  1. ❌ 3.1 - 14: Not supported
  2. ✅ 14.1 - 17.4: Supported
  3. ✅ 17.5: Supported
  4. ✅ 17.6 - TP: Supported

Firefox

  1. ❌ 2 - 78: Not supported
  2. ✅ 79 - 129: Supported
  3. ✅ 130: Supported
  4. ✅ 131 - 133: Supported

Opera

  1. ❌ 9 - 60: Not supported
  2. ✅ 62 - 110: Supported
  3. ✅ 111: Supported

IE

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

Chrome for Android

  1. ✅ 128: Supported

Safari on iOS

  1. ❌ 3.2 - 14.4: Not supported
  2. ✅ 14.5 - 17.4: Supported
  3. ✅ 17.5: Supported
  4. ✅ 17.6 - 18.0: Supported

Samsung Internet

  1. ❌ 4 - 10.1: Not supported
  2. ✅ 11.1 - 24: Supported
  3. ✅ 25: Supported

Opera Mini

  1. ❌ all: Not supported

Opera Mobile

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

UC Browser for Android

  1. ✅ 15.5: Supported

Android Browser

  1. ❌ 2.1 - 4.4.4: Not supported
  2. ✅ 128: Supported

Firefox for Android

  1. ✅ 127: Supported

QQ Browser

  1. ﹖ 14.9: Support unknown

Baidu Browser

  1. ﹖ 13.52: Support unknown

KaiOS Browser

  1. ❌ 2.5: Not supported
  2. ﹖ 3: Support unknown

Threads support in browsers also includes passive data segments (from the bulk-memory extension)

Resources:
Feature extension overview