How do we disable the snap stuff

[Bret Busby]

Upon booting one of my systems; UbuntuMATE 21.04, it immediately
starting downloading megabytes of stuff.

Upon checking, it was automatically downloading unknown upgrade stuff.

The settings in the "Software and Updates" application had been
changed by the software - against my will - so that, for "When there
are security updates", instead of the option "Display immediately",
the software had changed the setting to "Download and install
immediately". So, I immediately severed the Internet connection,
changed the setting back to what it should have been, according to my
choices, closed the application, to save the setting change, and,
restored the Internet connection.

Upon restoring the Internet connection, the massive downloading
resumed, so, I opened the "Software and Updates" application again,
and, noticed that it has a line of text "Snap packages are checked
automatically and installed  automatically."

As this snap stuff can not be trusted to not make unauthorised
changes, and, cannot be trusted to not sabotage the system operation
(this unauthorised snap interference probably explains the error
messages that I have been getting, about incomplete and partial
upgrades and resultant systems instability across my systems), how do
we disable this malicious snap thing?

-- 
Bret Busby
Armadale
West Australia
(UTC+0800)
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