Pour utiliser les extensions Android, vous aurez besoin de Firefox pour Android. Pour découvrir les modules complémentaires pour Firefox, veuillez visiter cette page.
Good news, I have just updated the addon. I would appreciate it if you could give it a try again, thanks!
Regarding your update with the question about syncing: the history should automatically be synced across computers as long as they are all logged into the same Youtube account.
