diff --git a/src/www/firewall_rule_lookup.php b/src/www/firewall_rule_lookup.php
index 618c76e80..072e474d8 100644
--- a/src/www/firewall_rule_lookup.php
+++ b/src/www/firewall_rule_lookup.php
@@ -67,3 +67,8 @@ if ($_SERVER['REQUEST_METHOD'] === 'GET') {
         // not found, XXX: figure out where to redirect to
     }
 }
+?>
+<script>
+    // close when not found
+    window.close();
+</script>