[pkg-apparmor] Bug#968387: apparmor: Broken printing and printer autodiscovery

[user]

Package: apparmor
Severity: grave
Justification: renders package unusable



I installed lxc on a freshly installed debian 10 (standard iso + the tasks:
desktop, kde, print-server, laptop).

- The printer was not autodiscovered in the "Print" window of any program,
  and in the "Add printer" window of system-config-printer-settings.
- Even after setting the device URI, print jobs did not make it to the printer
  and there were no info about toner levels, printer availability, etc.

I did not touch apparmor, but aa-status said it was enforcing on a lot
of programs, including /usr/sbin/{cupsd,cups-browsed}, so I ran

aa-complain /usr/sbin/cupsd
aa-complain /usr/sbin/cups-browsed

Now, the printer was autodiscovered, but printing still did not work, so I did

apt-get autopurge apparmor

Now printing works fine, I have toner level info, etc.