MV2 vs MV3 in Chrome and Firefox

128 views
Skip to first unread message

Jackie Han

unread,
May 21, 2022, 4:32:17 AMMay 21
to Chromium Extensions
I just read the blog from Firefox: Manifest v3 in Firefox: Recap & Next Steps (2022/5/18)

Here is a simple comparison:

Chrome MV2Chrome MV3Firefox MV2Firefox MV3
NetworkWebRequestdeclarativeNetRequestWebRequestWebRequest + declarativeNetRequest
Backgroundpersistent bg page + event pageservice workerpersistent bg page, event page(introduced from FF MV3)(limited) event page, service worker(in working)

Jackie Han

Cuyler Stuwe

unread,
May 21, 2022, 11:19:25 AMMay 21
to Chromium Extensions, Jackie Han
Did Firefox uh... forget to add content script support?! 🤔😅

I tried porting two simple MV3 extensions to Firefox (following their migration guide) and wasn't able to get any of the content scripts to work.

The only "trick" I could do to get them to be recognized was:
1. Change the manifest_version to 2 and load the extension like this.
2. Change the manifest_version back to 3.
3. Reload in-place in about:debugging.

Jackie Han

unread,
Jun 14, 2022, 1:10:03 PM (12 days ago) Jun 14
to Chromium Extensions
Reply all
Reply to author
Forward
0 new messages