diff --git a/layout/base/crashtests/412651-1-frame.xhtml b/layout/base/crashtests/412651-1-frame.xhtml
new file mode 100644
index 000000000000..80f10b544c67
--- /dev/null
+++ b/layout/base/crashtests/412651-1-frame.xhtml
@@ -0,0 +1,29 @@
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+<head>
+
+<style type="text/css" id="s"></style>
+
+<script type="text/javascript">
+
+function lo()
+{
+  window.onerror = oe; 
+  setTimeout(function(){ location.reload(); }, 200);
+}
+
+function oe(a,b,c)
+{
+  document.getElementById("s").textContent = ".nosuch { color: red }";
+}
+
+</script>
+
+</head>
+
+<body onload="lo();">
+  <xul:preference/>
+  <xul:tabs/>
+</body>
+
+</html>
diff --git a/layout/base/crashtests/412651-1.html b/layout/base/crashtests/412651-1.html
new file mode 100644
index 000000000000..4640061ca756
--- /dev/null
+++ b/layout/base/crashtests/412651-1.html
@@ -0,0 +1,21 @@
+<html class="reftest-wait">
+<head>
+<script type="text/javascript">
+
+var childLoads = 0;
+function inc()
+{
+  ++childLoads;
+  if (childLoads >= 2)
+    document.documentElement.removeAttribute("class");
+}
+
+</script>
+</head>
+
+<body>
+
+<iframe src="412651-1-frame.xhtml" onload="inc();"></iframe>
+
+</body>
+</html>
diff --git a/layout/base/crashtests/crashtests.list b/layout/base/crashtests/crashtests.list
index 441d7ee63add..6d19e602e428 100644
--- a/layout/base/crashtests/crashtests.list
+++ b/layout/base/crashtests/crashtests.list
@@ -107,3 +107,4 @@ load 409513.html
 load 409461-1.xhtml
 load 410967.html
 load 411870-1.html
+load 412651-1.html
