it would be nice if it could support all extensions like kiwi browser does for chromium on android.
It's unfortunate that both being able to install any addon and access about:config on mobile isn't just some checkbox away or at least more accessible without having to install Nightly. A few years ago both were available in the regular version.
One alternative is the F-Droid Fennec fork, which is said to enable both out of the box[2].
[1] https://blog.mozilla.org/addons/2020/09/29/expanded-extensio...
[2] https://reddit.com/r/firefox/comments/wu4g0s/mozilla_firefox...
About:config is there, but the absurd whitelist on extensions is still there. I cannot confirm what the reddit thread says.