
The usual recommendation for that problem is:
#Install firefox 40.0.3 update
Maybe a recent update corrupted your program folder, and the update failed to fix it. You mentioned "completely removing Firefox" but I'm not sure exactly how you did that. *if you do not see an item on a toolbar and in the Customize palette then click the Restore Defaults button to restore the default toolbar setup *if missing items are in the Customize palette then drag them back from the Customize window on the toolbar *if "Bookmarks Toolbar items" is not on the Bookmarks Toolbar then drag it back from the Customize palette into the Customize window to the Bookmarks Toolbar

*check that "Bookmarks Toolbar items" is on the Bookmarks Toolbar *"3-bar" menu button > Customize > Show/Hide Toolbars I can't do the second part because I can't drag anything at all. I can't even do the "design my own browser" feature because I literally unable to drag anything in Mozilla. But it's not just I can't drag my bookmark toolbar, I can't even drag my tabs in my tab bar. if you do not see an item on a toolbar and in the Customize palette then click the Restore Defaults button to restore the default toolbar setup.if missing items are in the Customize palette then drag them back from the Customize window on the toolbar.if "Bookmarks Toolbar items" is not on the Bookmarks Toolbar then drag it back from the Customize palette into the Customize window to the Bookmarks Toolbar.

#Install firefox 40.0.3 install
i am not able to install firebug add on in mozila firefox.

