Why does 18.04 not detect WiFi devices that 16.04 detects

[Bret Busby]

Hello.

I have UbuntuMATE running on different systems - mostly 16.04.x, but,
on one computer, I have 18.04 running.

One of the problems with 18.04, is that it does not detect WiFi
sources, that 16.04 detects.

Both detect my cellphone as a hotspot, okay, but I also have two WiFi
4G modem/routers, and, whilst 16.04.x sees them okay, and, can connect
to them okay, 18.04 does not see them, and, can not detect them.

I tried downloading and running WiFi radar and something named
LinSSID, but, while I can load WiFi Radar, it can only find my
cellphone, and nothing else (18.04 does see a WiFi printer that we
have; an HP one, that 16.04 can see, but WiFi Radar can not even see
that), and, LinSSID does not appear to load. Both of those
applications, are on 18.04.

So, I am wondering why 18.04 does not detect WiFi devices, that 16.04
finds without any problems.

-- 
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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