У вашего броузера проблема в совместимости с HTML5
Author Alan D Moore demonstrates a basic PyQt5 Hello World program, then transforms it into a template that you can use for all your PyQt5 programs.
Follow Alan at https://www.alandmoore.com
Purchase a copy of Mastering GUI Programming with Python here: https://www.amazon.com/Mastering-GUI-Programming-Python-cross-platform-ebook/dp/B07S9WFD92/
Example code for this video can be found here: https://github.com/alandmoore/PyQt-Videos-Examples/tree/master/HelloWorldqt
Default command line arguments for any Qt program:
https://doc.qt.io/qt-5/qapplication.html#QApplication
Thanks for watching!