Mozilla Firefox manifest v3 support is coming (eventually)

Mozilla announced that they would be working on Manifest v3 support almost a year ago. Mozilla set an ambitious deadline to provide developers a preview version in Q4 2021. And start accepting manifest v3 extensions submissions in early 2022. Eight months have passed. Where are we in 2022 March?

Short answer is that Mozilla has not made any public progress. None of the blocking issues are closed in the bug tracker. And there is no developer preview available. This is disappointing news.

Different manifest versions create fragmentation in the browser extension platform. It’s now harder to create extensions for multiple browsers by reusing the same code. Developers migrating to Manifest v3 can decide not to use v3 features like promises. And decrease code differences between v3 and v2. Developers that have created extensions following v3 best practices are in a worse situation. There are two options: refactor code or delay porting to a different browser for a year or so.

My guess is that Mozilla is monitoring Google’s struggle with Manifest v3 rollout. And have decided to wait. Google will iron out all the rough edges in Manifest v3 and then Mozilla will resume development.