How do you mean? I've been using it for a couple of months now and aside from one website (my bank) everything I've tried to do with it has been perfectly fine. It even has adblock and videos play in the background. I've also not seen any issues with dark mode; I'm using dark mode right now, actually.
I have auto dark mode during night time. In the morning, my phone will switch to light mode, but parts of the Firefox UI do not. It will be half in and out of dark mode. Bottom toolbar will be dark, but the top bar (notifications, battery, etc.) will be white text against white background. In the mornings, Youtube videos frequently wont play until I restart the app.
As far as I know, Firefox Mobile doesn't have a bottom toolbar so I'm not really sure what you are referring to there (at least, there's no bottom toolbar in Firefox on Android where I'm using it), and the notification/battery area is definitely not part of Firefox. It sounds like your phone's system UI is providing those elements, and it's likely not really fair to blame problems with the system UI on Firefox.
Firefox on Android can be configured with the address / tab bar at the bottom - possibly this is what they're referring to, but that also doesn't dynamically change per site as far as I'm aware.
It does have a bottom toolbar and was configured like that by default before. They must have changed the default some time ago.
System UI is just standard Google Pixel UI and it reacts to apps signaling to it what color theme it's in. Firefox just isn't signaling it correctly. It also should be reacting normally to dark mode toggle but it doesn't because the main Fx toolbar doesn't change to light mode in the mornings. No other app has this issue.
I totally agree, this has been my experience with FF mobile too. It's not a killer but it is a bit annoying, especially for those of us who still do use light mode when outdoors on a bright day.
Try the Firefox Beta instead of stable, no clue why, but it runs much better. You also get access to "about:config" back (they removed it from the stable version :-/).
Any browser without adblock is utter crap. So Firefox with uBlock Origin has been doing great for me. Try the Firefox Beta version, it somehow runs a lot better than stable.
There are features, like swiping the url bar to switch tabs, that are missing on the pre installed Chrome, but the firefox has them. Chrome has nothing to offer over firefox, besides your data collection
Ah, seems like it works now, it has been a while since I've used it. But it still doesn't have an option for moving the url bar to the bottom of the screen and blocking trackers.
Website incompatibility keeps me from using it 100%. Certain websites are simply non-functional except in a Chrome-based browser and I don't have the shits to give to swap only for those sites. I might start the day with Firefox and by the end I'm using Brave.
I switched back to Firefox about 2 years ago, and I've only encountered a few sites that don't work properly.
With the exception of ONE annoying SaaS site I need at work (which I might use a ton for a week then not again for weeks), I've only had to open a site in Chrome/edge maybe once a month. That includes running Firefox on my phone in addition to my work and personal desktop/laptops.