Could Not Find or Load the Qt Platform Plugin “xcb”

If you get the following message when trying to run QuantumATK on certain Linux platforms

 This application failed to start because it could not find or load the Qt platform plugin "xcb".

then you might need to install some additional xcb libraries. In order to find out what is missing exactly, one can add some debug output:

QT_DEBUG_PLUGINS=3 /path/to/installation/bin/quantumatk

This error may also prevent you from starting QuantumATK. In this case, especially if you double-clicked the Desktop icon, no error message is shown, but the text above can be found in the crashlog.txt file, which will be created in your user profile (aka home) directory at <user_profile_dir>/.quantumatk/crashlogs.

Read more in the FAQ page about system requirements for the desired version of QuantumATK.