Move the tab bar - Firefox
From MozillaZine Knowledge Base
Edit your userChrome.css file to add the code you need, as follows.
Move it to the Bottom
/* Display the tabbar at the bottom */
#content > tabbox {-moz-box-direction: reverse;}
Move it to the Left/Right Sides
/* Display the tabbar on the left */
#content > tabbox { -moz-box-orient: horizontal; }
.tabbrowser-strip { -moz-box-orient: vertical; /* note: you can set this to -moz-scrollbars-vertical instead, but then the scrollbar will *always* be visible. this way there is never a scrollbar, so it behaves like the tab bar normally does */ overflow: -moz-scrollbars-none; }
.tabbrowser-tabs { -moz-box-orient: horizontal; min-width: 10ex; /* you may want to increase this value */ -mox-box-pack: start; -moz-box-align: start; }
.tabbrowser-tabs > hbox { -moz-box-orient: vertical; -moz-box-align: stretch; -moz-box-pack: start; }
.tabbrowser-tabs > hbox > tab { -moz-box-align: start; -moz-box-orient: horizontal; }
/* remove the close-tab button */ .tabbrowser-tabs > stack { display: none; }
If you want to move it to the right, add the following lines to the above:
/* Instead, display the tabbar on the right */
#content > tabbox {-moz-box-direction: reverse;}
Unabashedly stolen from clav.