On desktop now, firefox already has a song playback that is better than that of Chrome/Edge. So it would make sense to work this out on mobile too, also for images I know it's not a priority, but I could work on it if someone guides me on how to do ...
Firefox Mobile (tested in Android) can't play local files (mp3 files or whatever). It's a shame, because this feature is on chrome. So to play music I have to either download some sketchy music player or use chrome.