I installed now the Debian-Iceweasel 3.5 from SID.
The bug is still present.
When using in KDE4 systemsettings -> appearance -> gtk style and fonts -> use
other style -> QT4
instead of qtcurve, firefox cant be terminated correctly. Sometimes xulrunner
is still running and consumes 99% CPU after closing Iceweasel, sometimes it is
firefox-bin. This bug occurs only when choosing using "other style".
When using "Use KDE style in gtk-applications" Iceweasel & Firefox terminate
But even if using that option, the style looks still very buggy on Firefox &
Iceweasel (please check it out yourself while using the described styles). The
tabs look crappy.
pkg-kde-extras mailing list