Comment 0 for bug 2016369

The application lrfviewer is crashing on latest Edubuntu Lunar (20230414.1).
Discovered during ISO Testing of
http://cdimage.ubuntu.com/edubuntu/daily-live/20230414.1/lunar-desktop-amd64.iso

Steps to reproduce:

1. Start lrfviewer via menu or via command line without any arguments

Error Message:

QApplication: invalid style override 'Adwaita' passed, ignoring it.
 Available styles: Windows, Fusion
Traceback (most recent call last):
  File "/usr/bin/lrfviewer", line 21, in <module>
    sys.exit(main())
             ^^^^^^
  File "/usr/lib/calibre/calibre/gui2/lrf_renderer/main.py", line 313, in main
    main = file_renderer(stream, opts, logger=logger)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/calibre/calibre/gui2/lrf_renderer/main.py", line 264, in file_renderer
    m = Main(logger, opts, parent=parent)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/calibre/calibre/gui2/lrf_renderer/main.py", line 73, in __init__
    self.setupUi(self)
  File "/usr/lib/calibre/calibre/gui2/lrf_renderer/main_ui.py", line 35, in setupUi
    self.graphics_view = BookView(parent=self.viewer_page)
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: BookView.__init__() got an unexpected keyword argument 'parent'