In QFontDialog, the accessible labelled-by relations between the lists (of class QFontListView) and their labels ("Font", "Font style", "Size") are missing. As a consequence, screen readers don't announce those labels when the lists receive focus, making it unclear to visually impaired users what those lists are about.

Steps to reproduce

1. start the Orca screen reader on Linux
2. build and run this sample program

   #include <QApplication>
   #include <QFontDialog>
   
   int main(int argc, char *argv[])
   {
       QApplication a(argc, argv);
       QFontDialog w;
       w.show();
       return a.exec();
   }
   

1. navigate through the dialog using the tab key and listen to the screen reader announcement

Actual result

When the lists mentioned above receive focus, the Orca screen reader doesn't announce the labels that visually label them.

Expected result

The screen reader should announce the labels when those lists receive focus so that screen reader users know what the lists are for.

Further information

An analysis with Accerciser reveals that the label-for relation from the label to the list is set, but the inverse labelled-by relation from the list to the label is missing, i.e. the accessible relations are inconsistent.