Use case:

• no .qtlicense file on the 'home' directory
• launch the Qt5 Commercial installer is launched
  --> message box is displayed; it asks licensee & license key

Currently the message box does not support installer scripts (.qs). Support for the installer scripts should be added for the message box. This is needed for Qt5 release test automation.

Note: testing the installer's license checker so that .qtlicense file already exists while running the installer is a different use case as described above. Thus it is not a proper workaround for the issue.