On 3.38 you can also remove these lines: prefsWidget.show_all(); prefsWidget.connect('destroy', Gtk.main_quit);

@JustPerfection: Thanks for the review, that was fast as lightning. I did not remove these two lines because this site (https://gjs.guide/extensions/upgrading/gnome-shell-40.html#show-all-and-destroy) says, that they are still needed for GTK3 based systems. Is that still valid?

I wrote in gjs.guide, you don't need that in GTK4 anymore since the port guide is about GNOME 40. To explain more about it here: If you write `prefsWidget.show_all();` you will get error in GTK4 since it doesn't have show_all() function but prefs window in GNOME 3.36 and 3.38 calls show_all() and destroy signal automatically. In other word, those two lines only needed until GNOME Shell 3.34.

Thank you for the explanation. I'll remove those lines in the next version.