I have noticed a annoying thing about Firefox in FC3.
If you want to change your connection settings its Edit => Preferences=> General
in Firefox for windows, its under Tools => Options => General in Thunderbird for windows its under Tools => Options => Advancedin Thunderbird for FC3 its under Tools => Options => Advanced Why not move the Preferences item from Edit to Tools and call it Options?
(i dont know if this is in FC3 only or a general thing with Firefox forlinux)