diff --git a/layout/style/test/test_bug580685.html b/layout/style/test/test_bug580685.html
index acea085dfe6d..4b492a839171 100644
--- a/layout/style/test/test_bug580685.html
+++ b/layout/style/test/test_bug580685.html
@@ -11,7 +11,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=580685
 <body>
 <a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=580685">Mozilla Bug 580685</a>
 <p id="display">
-  <iframe id="f" src="data:text/html,<body style='outline-offset: 1rem'>">
+  <iframe id="f" srcdoc="<body style='outline-offset: 1rem'>">
   </iframe>
 </p>
 <div id="content" style="display: none">
diff --git a/layout/style/test/test_pseudoelement_state.html b/layout/style/test/test_pseudoelement_state.html
index ad4bf5242d42..e0ca6afe2088 100644
--- a/layout/style/test/test_pseudoelement_state.html
+++ b/layout/style/test/test_pseudoelement_state.html
@@ -5,7 +5,7 @@
 <script src="/tests/SimpleTest/EventUtils.js"></script>
 <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css">
 
-<iframe src="data:text/html,<!DOCTYPE html><style></style><div></div>"></iframe>
+<iframe srcdoc="<!DOCTYPE html><style></style><div></div>"></iframe>
 
 <script>
 var gIsAndroid = navigator.appVersion.indexOf("Android") != -1;
