I will try to give another chance to the API. It was suppose to work "out of the box" or that's just what Mozilla says but when I put it on mobile everything was blank. No errors, no issue no nothing, just a blank screen, and I had to cancel mobile support because simply I had no idea what the issue was and/or what to do. But I will try to check again if things work better. Sadly if there is any need to redo the UI for mobile things might not be that straight-forward so I can't really promise anything.

P.S Just in case you were not aware: All your saved sessions (in bookmarks) are still accesiable on Firefox mobile if you look for them in Bookmarks->Menu->SessionSync. I know it's not ideal but at least there something and you can still look up for things if you really need to.