diff --git a/src/components/script/dom/webidls/AttrList.webidl b/src/components/script/dom/webidls/AttrList.webidl
index d37bb53a3b8..f9419f5ef62 100644
--- a/src/components/script/dom/webidls/AttrList.webidl
+++ b/src/components/script/dom/webidls/AttrList.webidl
@@ -2,7 +2,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+[NoInterfaceObject]
 interface AttrList {
   readonly attribute unsigned long length;
   getter Attr? item(unsigned long index);
-};
\ No newline at end of file
+};