I can confirm this bug is still happening in Gutsy Gibbon with Firefox 2.0.0.11 and with Minefield build 2008012004
I used the default Human theme for testing, both with Compiz enabled and disabled.
Firefox had a clean new theme with only adblock plus or greasemonkey installed. Both extensions had the same (buggy) behaviour.
I can confirm this bug is still happening in Gutsy Gibbon with Firefox 2.0.0.11 and with Minefield build 2008012004
I used the default Human theme for testing, both with Compiz enabled and disabled.
Firefox had a clean new theme with only adblock plus or greasemonkey installed. Both extensions had the same (buggy) behaviour.