Software updater snuck in a package that is unwanted

[Bret Busby]

How do I remove a package that was snuck in?

The Software updater apparently installed a package that was listed as
"Automatically install upgrades" or something like that, because I did
not know how to permanently block it.

Synaptic shows it (I think) as unattended upgrades", with the
description "automatic installation of security upgrades".

Apparently, this trojan horse has the effect that, to remove it, so as
to revert to manually performing upgrades (which is as it should be),
I have to wreck the system, by removing the desktop system and the
operating system core.

So, how do I remove this trojan horse, without destroying the system?

-- 
Bret Busby
Armadale
West Australia

..............

"So once you do know what the question actually is,
 you'll know what the answer means."
- Deep Thought,
 Chapter 28 of Book 1 of
 "The Hitchhiker's Guide to the Galaxy:
 A Trilogy In Four Parts",
 written by Douglas Adams,
 published by Pan Books, 1992

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