On the standards track: Yes
Is Experimental: No
Is Deprecated: No
In Chrome version 91 on 2021-05-25
In Chrome Android version 91 on 2021-05-25
In Edge version 91 on 2021-05-27
Not in Firefox
Not in Firefox for Android
Not in Internet Explorer
In Quest Browser version 16.0 on 2021-06-14
In Opera version 77 on 2021-06-09
In Opera Android version 64 on 2021-05-25
In Safari version 15 on 2021-09-20 Note: Nested workers support was introduced in Safari 15.5. Script loading in nested workers was introduced in Safari 16.4.
In Safari on iOS version 15 on 2021-09-20 Note: Nested workers support was introduced in Safari on iOS 15.5. Script loading in nested workers was introduced in Safari on iOS 16.4.
In Samsung Internet version 16.0 on 2021-11-25
In WebView Android version 91 on 2021-05-25
Not in WebView on iOS