1/ Part of the upcoming v21.12 release of @postmarketOS will be a modern mobile-config-firefox. I've just tagged 3.0.0_rc1 and made it available in postmarketOS edge for wider testing.
This is the biggest release so far, highlights:
* FF >= 91 compatibility
* navigation bar moved to bottom (thanks to plata-gl)
* reader view made adaptive (thanks to @blendergeek)
* much less UI glitches, no more tiny font hacks
* u-block origin installed by default