Good, but not what I was looking for Rated 4 out of 5 stars

While the extension performs its job quite well, it's been a bit misrepresented. I'm on Mac OS X, and the extension does not make Firefox behave like a full screen app, or like IE's Full Screen option would (i.e. usurping the entire screen, including the menu bar with the Apple menu and the Dock.) It merely sizes the window to maximum, while hiding all the toolbars and the status bar. While it is a good extension, anyone looking for true, complete fullscreen should give it a miss.