User-Agent: Mozilla/5.0 (Windows; Windows NT 6.1; WOW64; rv:2.0b2) Gecko/20100720 Firefox/4.0b2 Build Identifier: Mozilla/5.0 (Windows; Windows NT 6.1; WOW64; rv:2.0b2) Gecko/20100720 Firefox/4.0b2 When I close firefox by pressing alt f4 while in full screen mode, the title bar is small and does not have the regular 'minimise, maximise, close' buttons at the top left. This leaves the user with no ability to fix the problem other than pressing f11 twice to full screen the app and then restore. Reproducible: Always Steps to Reproduce: 1. Press F11 2. Press Alt+F4 3. Open Firefox Actual Results: The window chrome is not normal. Thin borders and no buttons on the top right of the window. Expected Results: regular window not full screened and it looks like the regular firefox window

I can confirm this. I achieved this by simply pressing the close button on the fullscreen toolbar. What happens is that Firefox is in a sort of semi-fullscreen mode after the restart. You need to press F11 again (or use the menu entries or so on) for Firefox to exit (instead of enter, as it should be) fullscreen. This is a blocker. Unless it's a duplicate.

Added Dão to the CC list in hopes this doesn't get lost. Sorry for the bother Dão. Again, I believe this is a blocker. Unless it's a duplicate.