Instead of using Muon or Synaptic as a frontend for the APT package manager you could also use it directly through a command line interface:
To be sure that HPLIP and its graphical user interface are installed as they should, you can open the Konsole terminal emulator from the
-> Application Menu -> System and enter (exactly as written)
sudo apt reinstall hplip (press [Return] and enter your password)
sudo apt reinstall hplip-gui (press [Return] )
To install python3-pyqt5 as claydoh suggested you could also use Konsole and enter
sudo apt reinstall python3-pyqt5 (press [Return] )
(it is already a dependency of hplip-gui - it does not hurt to check this explicitly, though)
PS: I suggest to use apt reinstall instead of just apt install to re-configure the packages.
To be sure that HPLIP and its graphical user interface are installed as they should, you can open the Konsole terminal emulator from the
-> Application Menu -> System and enter (exactly as written)
sudo apt reinstall hplip (press [Return] and enter your password)
sudo apt reinstall hplip-gui (press [Return] )
To install python3-pyqt5 as claydoh suggested you could also use Konsole and enter
sudo apt reinstall python3-pyqt5 (press [Return] )
(it is already a dependency of hplip-gui - it does not hurt to check this explicitly, though)
PS: I suggest to use apt reinstall instead of just apt install to re-configure the packages.
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