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chromium/third_party/blink/web_tests/fast/frames/resources/iframe-scroll-page-up-down-2.html 

<html>
<body contenteditable=true onclick="alert('clicked');">
<input id="focus1" value="focus here and page up">
<br>
2<br>
3<br>
4<br>
5<br>
6<br>
7<br>
8<br>
9<br>
<input id="focus2" value="focus here and page down">
</body>
</html>