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chromium/third_party/blink/web_tests/transforms/3d/general/background-visibility-layers.html 

<!DOCTYPE html>
<style>div { width: 100px; height: 100px } </style>
<div style="transform: rotateX(180deg); -webkit-transform-style: preserve-3d; background: green">
  <div style="backface-visibility: hidden; background: red;"></div>
</div>