Since the most recent update a few days ago Firefox (on my desktop PC) has been looking and behaving differently. The bookmarks sidebar has disappeared and can't be brought back in its previous form. Selecting ''Bookmarks toolbar - always show''' does nothing. There is no 'Back' arrow to return to a previous screen. I'm finding this new version almost impossible to use. Have I done something wrong? Can I go back to the previous version of Firefox? Regards, Peter