I use Firefox all the time mostly so I can just listen to music with the Google browser in the background without having the music stopping like YouTube. However, an annoying thing that does happen is that the music stops when there's an ad in one of my other apps. It's really annoying when I have to go back and restart it since I normally use desktop mode to listen to music in the background, but when I go back to fix the issue it goes to mobile mode and won't go back on to desktop mode.