firefox toolbar buttons don't work

Bookmarks missing, forward/back, bookmark, homepage ect buttons don't work, f5 doesn't work, upon opening firefox it does not open the previous sessions tabs (i have it set to do so in options menu) only a blank page. Possible problem: Before i noticed this problem i was changing my Newtab.url in About:config don't ask how but i managed to somehow mistakenly change browser.uicustomization.state this may or may not be the problem. Note: i have a lot of account for websites (that i cant remember the password for) and generally usefull stuff saved on firefox and i do not wish to lose these, so if all possible i would prefer not to reset firefox