Starting December 14, 2023, extensions marked as Android compatible on addons.mozilla.org (AMO) will be openly available to Firefox for Android users.
“We’ve been so impressed with developer enthusiasm and preparation,” said Giorgio Natili, Firefox Director of Engineering. “Just a few weeks ago it looked like we might have a couple hundred Android extensions for launch, but now we can safely say AMO will have 400+ new Firefox for Android extensions available on December 14. We couldn’t be more thankful to our developer community for embracing this exciting moment.”
In anticipation of the launch of open extensions on Android, we just added a link to “Explore all Android extensions” on AMO’s Android page to make it easy to discover new content. And just for fun and to offer a taste of what’s to come, we also released a couple dozen new open extensions for Android. You can find them listed beneath the Recommended Extensions collection on that AMO Android page. Try a few out!
It is opensource. The only thing that aren't are some required Google Play libraries for notifications and the EME - Firefox can't make those open as it doesn't control them.
https://github.com/mozilla-mobile/firefox-android
That's not enough. I want something that doesn't have any non-free software, period. It would be one think if it was just a matter of removing some notification libraries but the proprietary software is so tightly integrated that even Mull isn't completely free