In mozilla-thunderbird 1.5.0.5-0ubuntu0.6.06 the files: /usr/share/mozilla-thunderbird/icons/default.xpm /usr/share/mozilla-thunderbird/icons/mozicon16.xpm /usr/share/mozilla-thunderbird/icons/mozicon50.xpm
are not truly XPM files but Inkscape SVG files. Perhaps that is the reason. This also breaks the moztraybiff extension [1]. I have replaced them with the original icons [2] and now everything works fine. [1] http://moztraybiff.mozdev.org/ [2] http://www.ubuntuforums.org/showthread.php?t=199193 -- no icon for mozilla-thunderbird in KDE Panel https://launchpad.net/bugs/46760 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs