Your need to verify those addon work for current Firefox.

It's possible their buttons didn't fit on the toolbar, and are on the drop-down from the Extensions (puzzle piece) button. The following article has more information on that button and its drop-down: [[Manage your extensions using the extensions button in the toolbar]]. When you are using a private window, an additional possible issue is that you might not have granted permission to run in private windows at install time. Of course, you can add/remove this later, too. See: [[Extensions in Private Browsing]]. Were either of those relevant?