Addon fixes most problems the normal twitch player has on firefox (freeze issue)
I have only some minor nitpicks that would be nice if they could be adressed:
-Twitch currently will not recognize me as viewing the stream with this player, so I do not earn any channel points (need to open the stream in normal player with lowest quality+mute in second tab to fix that)
Edit: seems this was fixed in latest version of the addon :) Cheers!
-raids don't work properly (Chat connects to new stream that was raided, but the player doesnt)