chromium/third_party/blink/web_tests/fast/dom/inert/resources/inert-focus-in-frames-frame1.html

<!DOCTYPE html>
<html>
<head>
<script>
window.onload = parent.parent.frameLoaded;
</script>
</head>
<body>
<dialog id="dialog">
    <button id="dialog-button" tabindex="0">Button</button>
</dialog>
<input id="frame1-input" class="target" type="text">
<iframe id="iframe1" srcdoc='
    <dialog id="iframe-dialog">
        <button id="iframe-dialog-button" tabindex="0">Button</button>
    </dialog>
    <input id="iframe-input" class="target" type="date">
    <script>window.onload = parent.parent.parent.frameLoaded;</script>
'>
</body>
</html>