If you use Linux and know how to edit your userChrome.css file, you can get rid of the superfluous tab bar by adding this line: #tabbrowser-tabs { visibility:

If you use Linux and know how to edit your userChrome.css file, you can get rid of the superfluous tab bar by adding this line: #tabbrowser-tabs { visibility: collapse !important; } Be warned that on Windows this kills the hidden "alt" menu bar and hides the close, expand, and minimize buttons. Works perfectly on linux though :P, I haven't tried on OSX.