diff --git a/layout/generic/crashtests/307979-1.html b/layout/generic/crashtests/307979-1.html
new file mode 100644
index 00000000000..eb73d121539
--- /dev/null
+++ b/layout/generic/crashtests/307979-1.html
@@ -0,0 +1,27 @@
+<html class="reftest-wait">
+<head>
+
+<title>Crash testcase</title>
+
+<script>
+
+function foo()
+{
+  document.body.appendChild(document.createElement('frameset'));
+  setTimeout(bar, 30);
+}
+
+function bar()
+{
+  document.body.style.display = '-moz-groupbox';
+  document.documentElement.removeAttribute("class");
+}
+
+</script>
+
+</head>
+
+<body onload="setTimeout(foo, 30);">
+
+</body>
+</html>
diff --git a/layout/generic/crashtests/crashtests.list b/layout/generic/crashtests/crashtests.list
index 42eb0dfd202..e0521246189 100644
--- a/layout/generic/crashtests/crashtests.list
+++ b/layout/generic/crashtests/crashtests.list
@@ -1,3 +1,4 @@
+load 307979-1.html
 load 331284-1.xhtml
 load 334105-1.xhtml
 load 334147-1.xhtml
