THANKS so much The Hasagi, that did the trick. Cheers Robert
NOTE accurate path is from the Mac HD Library and not the User library, can be confusing
THIS - ComputerName/MacHD/Library/Application Support/com.adguard.Adguard/NfApiConfiguration/SSL/Adguard Personal CA.cer
I have had to install Firefox 61.0.1 to run a publishing system.
On my Mac Mini with no Adguard everything is fine
On my MacBook with AG 1.5.8 it blocks every website saying "Your Connection is Not Insecure" and insisting that totally valid site certificates are invalid. I can't even log into...