diff --git a/openslides/agenda/views.py b/openslides/agenda/views.py
index 3c7268d3e..9333de7c3 100644
--- a/openslides/agenda/views.py
+++ b/openslides/agenda/views.py
@@ -50,6 +50,13 @@ class Overview(TemplateView):
         else:
             items = Item.objects.filter(type__exact=Item.AGENDA_ITEM)
 
+        # Save the items as a list (not a queryset). This is important,
+        # because in other case, django-mtpp reloads the items in the
+        # template. But we add some attributes (in this function), which are
+        # not in the database and would be lost if the items were reloaded.
+        # TODO: Try to remove this line in later versions of django-mptt
+        items = list(items)
+
         start = config['agenda_start_event_date_time']
         if start is None or len(start) == 0:
             start = None