Rid Firefox of an extension??

[Beartooth]

	I'm running Firefox 24.0 on F18. It keeps telling me I have an 
update for AdblockPlus, but when I try to install it, it fails. I've 
tried doing it with AdblockPlus enabled, and with it disabled. There is 
no button on this extension, as there is on normal ones, to remove it. 
How do I just get rid of the whole extension?

	Is there an item or a line in my .mozilla, for instance, where I 
can just delete it?
-- 
Beartooth Staffwright, Neo-Redneck Not Quite Clueless Power User
Remember I have precious (very precious!) little idea where up is.