lingo: don't display invoice cells to anonymous users (#11118)

combo/apps/lingo/models.py

@@ -400,6 +400,9 @@ class Items(CellBase):
     def is_enabled(cls):
         return Regie.objects.count() > 0
 
+    def is_relevant(self, context):
+        return (getattr(context['request'], 'user', None) and context['request'].user.is_authenticated())
+
     def get_default_form_class(self):
         fields = ['title', 'text']
         widgets = {}