I know it's bleeding edge and asking a lot in a technical sense but how about letting us set what our homepage actually is? I know in the ~35 years browsers have existed, this has been an elusive feature but if anyone can do it, it is Mozilla.
We don't even have it on desktop, yet. I wouldn't use them as much as I do at work, where I use them to actively manage dynamic workflows. But it sure would be nice to be able to collapse some shopping tabs I typically have open, into one pinned tab group, or researching various projects.
Once they do it, I sure hope they put some more thought into how pinned tab groups should behave. They should either be to the left of all pinned tabs, or between pinned tabs and unpinned tabs. It drives me crazy in Edge, how new tabs tend to open to the left of my pinned tab groups.
Actually, I exclusively use Firefox Focus on my phone, so I don't really care there. But I do wish they'd get out of this half-assed support for tabs, there. Just let me create new tabs without long pressing links. Maybe put a limit on number of tabs to 3 or 5. I'd also love to have a "send to desktop" option, without having to go to regular Firefox and tab sync.
If you're learning Japanese, then "10ten" is very good. It adds a little "puck" you can use to hover over words and phrases to see their dictionary definitions, readings, etc.
(On desktop, it instead works whenever yoy hover your mouse cursor over a word, but on mobile, that's not a thing. Either way, it's easy to turn on/off based on your need.)
Nice for people that need it but I basically only require 2 - 3 extensions for mobile browsing and they were all supported already. There is a lot of overlap and extension redundancy out there. Many people still think they need like 5+ different privacy related extensions, for example, when uBlock Origin can do basically everything (including removing paywalls).
We don't need more browser extensions, we need isolation per site and Gecko based webview to be able to stand up to Chromium based browsers and their unfair monopoly.
They are working on it. They finally introduced full passwordless Webauthn on Linux and Mac about 5 versions ago. This work was part of the preparations for passkeys. It's coming.
There was a firefox dev who explained a bit about all this somewhere in a comment thread on hacker news but I forgot to favourite or bookmark it :(