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chromium/third_party/blink/renderer/core/testing/data/fullscreen_video.html 

<!DOCTYPE html>
<body style="border: 10px solid red">
    "Body text"
    <video src="test.webm" id="video" autoplay controls></video>
    <div id="other" style="will-change: transform; transform: translate(1px, 1px);">
      "Other text"
    </div>
</body>