If an old ThinLinc package is removed when installing a new version it should be shown to the admin. But on Ubuntu/Debian this is broken if more than one package is obsoleted.
It should be rare that this happens in reality right now since you need to upgrade from a very old ThinLinc when the packages 'thinlinc-vsm-server' and 'thinlinc-vsm-agent' still existed. But you can still see the effects of the bug in the installer log, we look for an empty package '':
> 2021-06-09 16:31:40,252: Checking 'thinlinc-vsm_4.12.1post-2122_amd64.deb'...
> 2021-06-09 16:31:40,308: Failed to get information about package ''
> 2021-06-09 16:31:40,308: dpkg-query: no packages found matching
> 2021-06-09 16:31:40,331: Failed to get information about package 'thinlinc-vsm-server'
> 2021-06-09 16:31:40,331: dpkg-query: no packages found matching thinlinc-vsm-server
This has probably been an issue since tl-4.9.0 when 'thinlinc-rdesktop' was removed (bug 7279).
Tested an upgrade from tl-4.9.0 to Jenkins build 2129, on Ubuntu 20.04.
✓ 'thinlinc-rdesktop' is shown as removed.
✓ Nothing about empty package '' in the log.
✓ Everything is installed as expected.
I reproduced the issue when upgrading the server from 4.9.0 to 4.12.1.
When upgrading from 4.9.0 to Jenkins build #2128 no empty package names are logged, `thinlinc-rdesktop` is removed and the install works as expected.
Marking as closed.