Ensure to add the cron forkhood worker task with medium priority

src/Worker/Cron.php

@@ -55,7 +55,7 @@ class Cron
 		}
 
 		// Fork the cron jobs in separate parts to avoid problems when one of them is crashing
-		Hook::fork($a->queue['priority'], 'cron');
+		Hook::fork(PRIORITY_MEDIUM, 'cron');
 
 		// Poll contacts
 		Worker::add(PRIORITY_MEDIUM, 'PollContacts');