When you open (window.open) window, then manualy resize to the smaller, the status bar is overscrolled by bottom border and then is no possible to resize window because no corner for catch is visible. The bottom button of scrollBar get hidden too.
Do you still see this with Firefox 3.6.3 or later in a new profile?
No reply, INCOMPLETE. Please retest with Firefox 3.6.13 or later and a new profile (http://support.mozilla.com/kb/Managing+profiles). If you continue to see this issue with the newest firefox and a new profile, then please comment on this bug.