You can reset just Firefox's toolbars.

Alt+v to display classic View menu > Toolbars > Customize

Click the button "Restore default set"

Does it help?

See also:

• http://kb.mozillazine.org/Corrupt_localstore.rdf

Oh, i found another problem. I cant even use drag-drop in firefox, like changing tab order. ps: still cant customize my toolbar.

I'd recommend you to check your add-ons and disable them one-by-one to see if one of them is causing the problem.

I had this problem too and disabling Torbutton did the trick for me. There seems to be some problems with Torbutton regarding this matter: https://trac.torproject.org/projects/tor/ticket/5839

Here are the instructions for disabling and removing add-ons: Disable or remove Add-ons