I hope I don't step on people's toes with this MR, but here is the port of properties window to GtkListBox.
If I may, maybe instead of using
gtk_builder_add_from_resource we can use template and
BaconVideoWidgetProperties will inherit from HdyWindow or GtkDialog instead of a
GtkBox ? Of course, it will probably bring some change in the way the values are updated (I talk about