Made lectures of unlisted videos accessible

server.py

@@ -299,7 +299,7 @@ def lecture(id):
 			lecture['id'], lecture['course_id'])
 	if not videos:
 		flash('Zu dieser Vorlesung wurden noch keine Videos veröffentlicht!')
-	courses = query('SELECT * FROM courses WHERE id = ? AND (? OR (visible AND listed))', lecture['course_id'], ismod())
+	courses = query('SELECT * FROM courses WHERE id = ? AND (? OR visible)', lecture['course_id'], ismod())
 	if not courses:
 		return render_endpoint('courses', 'Diese Veranstaltung existiert nicht!'), 404
 	chapters = query('SELECT * FROM chapters WHERE lecture_id = ? AND NOT deleted AND (? OR visible) ORDER BY time ASC', id, ismod())