How do I configure the switching sequence for WiFi networks connections - UbuntuMATE 19.10

[Bret Busby]

Hello.

I am running UbuntuMATE 19.10 on this computer.

We have a number of different WiFi  devices; each is regarded as a
separate WiFi network.

We also have neighbours' WiFi devices, which show when the computer is
not connected to a network (on 19.10, when it is connected to a
network, it shows only the WiFi device to which it is connected, and,
does not show any other WiFi device - it only shows all accessible
WiFi devices, when it is not connected to a network, whereas 16.04
shows all accessible WiFi devices, also when it is connected to a WiFi
network).

When I have the computer connected to my cellphone as a WiFi hotspot,
which I do as the primary WiFi network access for the computer, and, I
take the cellphone out of the room, and go to the other end of the
house, or, outside the house, the computer (running UbuntuMATE 19.10)
then, after a while, switches to another WiFi device, seeking Internet
access, most often, the photovoltaic inverter (which uses its WiFi, to
connect to a modem/router, to upload its data to the manufacturer's
facility), through which, the computer (or, more correctly, the OS)
can not access the Internet.

Sometimes (but, not the most often occurence), that computer, running
19.04, switches its WiFi connection to the modem/router, when the
connection to the cellphone is lost to it, and, thus, on those
occasions, mainatins connection to the Internet, through the WiFi
access.

The computer running 16.04, however, is connected by WiFi, to the
modem/router, and so, keeps merrily connected.

Does provision exist, and, if so, how do I implement it, to set the
preference order of switching the WiFi network connections, when a
WiFi connection is lost, in 19.04?

Thank you in anticipation.

-- 
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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