What I don't get is why Mozilla allows extensions to disable the "disable" and "uninstall" buttons at all. The program makes to wait 5 seconds when you add extensions through the program, but doesn't warn you that a 3rd party installed an extension. Also, that registry key for extensions probably should even exist.
The reason reason this feature was removed was to keep from having a thread repeatedly checking the floppy drive. I'm sure CD-ROMs and such send an interupt when discs are inserted, but not the floppy drive.