User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; sk; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; sk; rv:1.9.2.2) Gecko/20100316 Firefox/3.6.2 Auto hide menu is possible only in full screen mode. Reproducible: Always Steps to Reproduce: 1. F11 2. 3. Actual Results: Auto hide of menu only in full screen mode. Expected Results: Auto hide of menu also in normal window (not only in max window via F11). I hope you know what I mean :-) Thanks and have a nice day :-)

Hiding the menubar by default, and letting it popup when you need it, is already possible. Use View->Toolbar->Menubar to hide the menu. You can pop it up with the alt key. It should be improved in bug 555576, mainly for the auto-hiding part.

This was implemented by bug 456535 for Firefox 3.6. Bug 555576 aims to do the same for Thunderbird, which is not relevant here.