diff --git a/testing/web-platform/tests/html/browsers/the-window-object/named-access-on-the-window-object/window-named-properties.html b/testing/web-platform/tests/html/browsers/the-window-object/named-access-on-the-window-object/window-named-properties.html
index ebca18d0339d..0ec25812d0b8 100644
--- a/testing/web-platform/tests/html/browsers/the-window-object/named-access-on-the-window-object/window-named-properties.html
+++ b/testing/web-platform/tests/html/browsers/the-window-object/named-access-on-the-window-object/window-named-properties.html
@@ -60,7 +60,7 @@ test(function() {
 }, "constructor");
 test(function() {
   var gsp = Object.getPrototypeOf(Object.getPrototypeOf(window));
-  assert_equals(gsp.baz, document.getElementsByTagName("iframe")[1]);
+  assert_equals(gsp.baz, document.getElementsByTagName("iframe")[1].contentWindow);
 }, "duplicate property names")
 var t = async_test("Dynamic name")
 var t2 = async_test("Ghost name")