It's a great browser for Android. You get superior ad blocking and background video playing, extensions like dark reader...
Now browsers will be allowed to use their custom engine (they were forced to all use Safari up until now), so thank you EU for the new DMA!
Admittedly I haven't tried disabling extensions and finding the root cause. I just switch to Chrome for that task.
No doubt Chrome's more modern stack and hefty resources help in ironing out hardware-specific quirks.
By the way, I actually use Fennec from F-Droid and not Firefox from the Google Play Store, if that matters.
I've been meaning to try different Firefox distributions though because switching away from Firefox isn't really an option for the reasons you've stated.