diff --git a/components/script/dom/webidls/Window.webidl b/components/script/dom/webidls/Window.webidl
index d9a87650413..60cc45f5161 100644
--- a/components/script/dom/webidls/Window.webidl
+++ b/components/script/dom/webidls/Window.webidl
@@ -33,6 +33,7 @@
   readonly attribute Window frames;
   //[Replaceable] readonly attribute unsigned long length;
   //[Unforgeable] readonly attribute WindowProxy top;
+  readonly attribute Window top;
   //         attribute any opener;
   //readonly attribute WindowProxy parent;
   readonly attribute Window parent;
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index be9a3ccc5df..b781d7e19a1 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -442,6 +442,15 @@ impl<'a> WindowMethods for &'a Window {
         self.parent().unwrap_or(self.Window())
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-top
+    fn Top(self) -> Root<Window> {
+        let mut window = self.Window();
+        while let Some(parent) = window.parent() {
+            window = parent;
+        }
+        window
+    }
+
     fn Performance(self) -> Root<Performance> {
         self.performance.or_init(|| {
             Performance::new(self, self.navigation_start,
diff --git a/tests/wpt/metadata/old-tests/submission/Opera/script_scheduling/034.html.ini b/tests/wpt/metadata/old-tests/submission/Opera/script_scheduling/034.html.ini
deleted file mode 100644
index b1b921d5860..00000000000
--- a/tests/wpt/metadata/old-tests/submission/Opera/script_scheduling/034.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[034.html]
-  type: testharness
-  [ scheduler: innerHTML adding frames with JS in]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/old-tests/submission/Opera/script_scheduling/039.html.ini b/tests/wpt/metadata/old-tests/submission/Opera/script_scheduling/039.html.ini
deleted file mode 100644
index 3fdc17dfa9c..00000000000
--- a/tests/wpt/metadata/old-tests/submission/Opera/script_scheduling/039.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[039.html]
-  type: testharness
-  [ scheduler: IFRAMEs added with DOM]
-    expected: FAIL
-