Great !!! Rated 5 out of 5 stars
I forgot to mention in my previous comment that, those who use the so called 'Zombie Mode' ... we usually use it as a substitute of 'Fullscreen Mode' ... so that the possible remaining 'states' of Firefox window would be :
Minimized -- Unmaximized -- Maximized -- 'Zombie Mode'
... in contrast to the usual ...
Minimized -- Unmaximized -- Maximized -- Fullscreen
... this way, having available the 'Zombie Mode' does not restrict us from using the regular Maximized mode whenever it's required.
Thanks a lot.
Ps .- I am running Firefox 18.0 over a Kubuntu 12.04 amd64 box.