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chromium/third_party/blink/web_tests/paint/overflow/composited-scroll-vertical-rl.html 

<!DOCTYPE html>
There should be a green square.
<div style="width: 200px; height: 200px; overflow: scroll; will-change: transform; writing-mode: vertical-rl">
  <div style="width: 2000px">
    <div style="width: 100px; height: 100px; background: green"></div>
  </div>
</div>