chromium/third_party/blink/manual_tests/textarea-iframe-navigation.html

<html>
<head>
</head>
<body>
<p>Textarea inside iframe -- Navigation</p>
    <ol>
        <li>In the Debug menu, click "Go to about:blank soon"</li>
        <li>Select a few lines in the textarea, keeping the mouse cursor down inside the area</li>
        <li>Wait for the navigation to happen</li>
        <li>Release the mouse</li>
    </ol>
<p>You should not crash.</p>
<hr>
<iframe style="border: 2px solid black" width="100%" src="textarea-iframe-navigation2.html">
</iframe>
</body>
</html>