When you use QSettings IniFormat, an empty list is stored in the .ini file as @Invalid(). When you retrieve the value, you get 'None'. This obviously can cause problem when you expect a list.
Using defaultValue=[] doesn't help, you still get None.
As a workaround you can do something like
foo = settings.value('my_list) or []
But is there also a way to retrieve an empty list directly from the .ini file?
It could be that this is only an issue on Windows. (see https://github.com/frescobaldi/frescobaldi/issues/1137)