I had this issue but fixed it by having Firefox running (but with the issue of being minimized) and then killing the process in Task Manager. Restarted Firefox and everything was fine.

Got this problem too, since Firefox 12 (but it might have been caused by something else). I uninstalled Firefox 13 then reinstalled it (though I did leave my preferences, etc). This worked for that one day then when I did a restart of Win 7 Firefox has gone back to hiding by the taskbar again. I'll try a clean reinstall without keeping my preferences but I'm losing patience with Firefox; none of the other browsers do this. Even IE is more reliable! Andrew Win 7 64 bit, SP1, Firefox 13, Noscript current (I can't give the version as, hey, it's on Firefox which is acting shy)

reinstalling firefox can get u rid of this problem, i had this problem and i reinstalled my firefox that fixed the bug

tried that, bug still present but this seems to be a workaround; start FF as usual, it scurries off to the taskbar and hides as usual; L click on icon to bring up small picture of what FF is doing; R click on small picture and select "maximise"; FF should now display and run as normal. This is after today's Windows 7 updates, but is a suggestion not a guaranteed fix.

In fact, while checking FF for my version of NoScript , FF crashed again. Don't know what they've done to it but it's getting beyond a joke. Andrew (Win 7 Home Premium 64 bit, SP1, FF 13, NoScript 2.4.6)