Make sure that you do not run Firefox in full screen mode (press F11 or Fn + F11 to toggle; Mac: command+Shift+F). If the menu bar is hidden then press the F10 key or hold down the Alt key to make the menu bar appear. Make sure that toolbars like the "Navigation Toolbar" and the "Bookmarks Toolbar" are visible: "View > Toolbars" *Open the Customize window via "View > Toolbars > Customize" *Check that the "Bookmarks Toolbar items" is on the Bookmarks Toolbar *If the "Bookmarks Toolbar items" is not on the Bookmarks Toolbar then drag it back from the toolbar palette in the customize window to the Bookmarks Toolbar *If missing items are in the toolbar palette then drag them back from the Customize window on the toolbar *If you do not see an item on a toolbar and in the toolbar palette then click the "Restore Default Set" button to restore the default toolbar set up *http://kb.mozillazine.org/Toolbar_customization *https://support.mozilla.org/kb/Back+and+forward+or+other+toolbar+items+are+missing