First thing to check is to make sure Firefox isn't in full screen mode. There are two kinds: * Browser full screen -- the F11 key switches into and out of this mode * Content full screen -- usually there's a button on a video player that enters this mode, and you can press the Esc key to cancel it If you have lost your customizations to the toolbars, one possible reason is that Firefox started up in the wrong profile, and another is that the Firefox "Refresh"/"Reset" feature ran. Are you missing any other data such as bookmarks (well, if you use Firefox Sync, you might have gotten those back by now, but when you first started Firefox)? You could check the first section of this article to explore available profiles: [[Recover lost or missing Bookmarks]]. If Firefox Refresh ran, there would be a folder on your Windows desktop named Old Firefox Data and inside, there would be files with fresh time stamps. Do you see anything like that?