diff --git a/xhr/setrequestheader-header-allowed.htm b/xhr/setrequestheader-header-allowed.htm
index cd11e334a0f36d..14b7187d3ac662 100644
--- a/xhr/setrequestheader-header-allowed.htm
+++ b/xhr/setrequestheader-header-allowed.htm
@@ -28,6 +28,7 @@
       request("If")
       request("Status-URI")
       request("X-Pink-Unicorn")
+      request("!#$%&'*+-.^_`|~0123456789abcdefghijklmnopqrstuvwxyz")
     </script>
   </body>
 </html>