/usr/lib/mozilla/plugins:
  => librhythmbox-itms-detection-plugin.so
        (size: 6080 bytes, mtime: Thu Sep 20 01:02:45 2012)
  => libtotem-gmp-plugin.so
        (size: 105440 bytes, mtime: Tue Sep 18 23:10:03 2012)
  => libtotem-narrowspace-plugin.so
        (size: 80576 bytes, mtime: Tue Sep 18 23:10:03 2012)
  => libtotem-cone-plugin.so
        (size: 100736 bytes, mtime: Tue Sep 18 23:10:03 2012)
  => libgnome-shell-browser-plugin.so
        (size: 18840 bytes, mtime: Thu Sep 27 15:08:37 2012)
  => libtotem-mully-plugin.so
        (size: 72048 bytes, mtime: Tue Sep 18 23:10:03 2012)

/usr/lib/firefox/plugins: