Ticket #20959: 20959.2.diff

wp-admin/includes/update.php

@@ -137 +137 @@
         echo "<div class='update-nag'>$msg</div>";
 }
 add_action( 'admin_notices', 'update_nag', 3 );
+add_action( 'network_admin_notices', 'update_nag', 3 );
 
 // Called directly from dashboard
 function update_right_now_message() {