The Firefox screen has shrunk to cover less than the top half of my screen, full width. The maximize button makes the position jump a fraction of an inch up and to right or left; depending on where the "full" screen is positioned; but it will not expand lengthwise to fill the lower portion of the monitor. I've tried dragging the bottom, but it snaps back, won't expand by dragging.

This is the second time it has happened in as many days. I can't remember what happened yesterday to fix it, but it isn't happening today. It started when I was on a game; Frontier Ville, by Zynga; on Facebook. A popup screen which comes up often asked whether I wanted to publish a reward to all my friends. I chose to skip publishing it, after which the screen shrank. I believe this is what happened yesterday too.

Do you have that problem when running in the Firefox SafeMode? http://support.mozilla.com/en-US/kb/Safe+Mode Don't select anything right now, just use "Continue in SafeMode."

If not, see this: http://support.mozilla.com/en-US/kb/troubleshooting+extensions+and+theme...

my screen is stuck in half screen and I can't stretch it out to full screen

Thanks. I don't know how to run in Firefox safe mode. I have found that by opening a second window (not tab) of Firefox I can get full screen.

I wanna maximize the browser

My screen is stuck pn 1/3rd also, and it began while trying to play frontierville by Zynga also!! what the heck!, tried in safe mode, still is stuck, cant open by dragging, rebooting, safe mode, nothing seems to fix this, I even deleted and reinstalled firefox, still have the the same problem...!!???