Help! Do I get this Annoying Floating Bookmarks Menu to go away?!

i was using firefox and i accidentally clicked on something and this bookmark menu popped up it doesnt move, it doesnt close, but the links within (i whited them out for privacy purpose) are active and clickable

i tried quitting firefox and it still remains floating and covering part of the screen .

i cant restart my computer because im running a bunch of applications right now

how do i get this thing to go away!?

pls see here