Comment 2 for bug 764642

I solved this problem it seemed like nothing but what had happened with me before this problem was that I had installed a package called gtk2-engines-murrine after which the problem started.
but after I uninstalled that package restarted same thing.
I remember that the package mentioned something about RGBa so I uninstalled gtk2-module-rgba and gtk2-engines-murrine restarted opened thunderbird it worked.
I re-installed those 2 packages and everything worked fine.