Password apparently changed by system update

[Bret Busby]

Hello.

On my other computer, I have UbuntuMATE 19.04 installed.

In the last few hours, a system update was shown as being available,
including something to do with giving some users extra superuser
privileges.

I do not know whether it was that component that was responsible, but,
after locking the screen when going away from the computer for a
while, when I tried to log in, I have found that the password has been
changed.

Is this an intended effect of the system update, and, how do I get
around the operating system having changed the login password on me?

-- 
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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