chromium/chrome/test/data/extensions/api_test/automation/sites/reverse_relations.html

<!--
Copyright 2017 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->
<html>
<head>
<title>Automation Tests - Relations</title>
</head>
<body>

<button id="detailsFrom" aria-details="detailsTo">DetailsFrom</button>
<h3 id="detailsTo">DetailsTo</h3>

<input id="input" aria-labelledBy="label1 label2">
<h3 id="label1">Label1</h3>
<h3 id="label2">Label2</h3>

</body>
</html>