When I first open Firefox 4.01, everything is fine. Since I have two monitors, I like to keep two windows open. When I open the second window, URLs do not show up in the location field, I can't refresh a page, there's an orange Firefox menu in the upper corner and a double window, the bookmarks don't show unless I do options/uncheck Bookmaks toolbar, then check it again.

I tried disabling all plugins, rebooted my computer -- nothing changed.