G'day Ivor, and Welcome to linux.org
The model number/name etc of the wifi adaptor would be a good start
Thanks for the response Wizard(Not an Aussie I'm afraid, I'm actually a New Zealander!)G'day Ivor, and Welcome to linux.org (snap, another Aussie here)
Have you checked this at your Linux Mint Forum spot
https://forums.linuxmint.com/viewtopic.php?f=53&t=301580&p=1687200&hilit=RTL8811CU#p1687200
If so, what was the outcome?
We do not usually try to answer questions that are being posted at more than one site concurrently, it is just too confusing.
Cheers
Chris Turner
wizardfromoz