Not really, but thanks for trying!
After the command line stuff above and a reboot, I got the same errors as
before when attempting the "upgrading of KDE Neon User Edition 5.19 to
version 20.04" as follows.
"Some Third party entries in your sources list were disabled. You can
enable them after upgrade with 'software-properties' tool in your package
manager".
After closing that error window, another error window says:
"Can't install Neon-desktop report as a bug using
'ubuntu-release-upgrader-core' in a terminal".
Close that window and get a third error window saying:
"Could not determine the upgrade, likely to be due to unofficial software
packages not provided by Ubuntu. Please use tool 'ppa-purge' from the
ppa-purge package to remove software from a Launchpad PPA and try the
upgrade again. Can investigate this by looking at log files in ......"
zzzzz....
This reminds me of problems upgrading Mickey$oft Windows on my Wife's
computer sometime ago: error windows and a refusal to upgrade. When I have
recovered, I'll have a look at the log files.
