If you are the administrator of a specialization you can recreate this behavior the following way:
Go to "Übersicht"
Click on the Fachgebiet you are the administrator of
Click on one of the specializations
Click on "Neuen Kurs erstellen"
Once the course is created and you go back to the page of the Fachgebiet the course will not appear there. You need to go and add the course via the "Existierenden Kurs hinzufügen" button. This is not the most intuitive behavior.
If you are the administrator of a specialization you can recreate this behavior the following way:
Go to "Übersicht"
Click on the Fachgebiet you are the administrator of
Click on one of the specializations
Click on "Neuen Kurs erstellen"
Once the course is created and you go back to the page of the Fachgebiet the course will not appear there. You need to go and add the course via the "Existierenden Kurs hinzufügen" button. This is not the most intuitive behavior.