chromium/third_party/blink/web_tests/compositing/geometry/fixed-in-composited.html

<!DOCTYPE html>

<html>
<head>
  <style type="text/css" media="screen">
    body {
      margin: 0;
      height: 1000px;
    }

    .container {
      position: absolute;
      z-index: 1;
      left: 95px;
      top: 145px;
      width: 50px;
      height: 50px;
      outline: 4px solid black;
    }
    
    .fixed {
      position: fixed;
      background-color: green;
      height: 100px;
      width: 100px;
      top: 20px;
      left: 20px;
    }
    
    .composited {
      will-change: transform;
    }
    
    .container.two {
      left: 200px;
      top: 100px;
    }
    
    .container.three {
      left: 400px;
      top: 100px;
    }
    
    .box {
      width: 100px;
      height: 100px;
    }

    .composited.box {
      width: 60px;
      height: 60px;
    }
    
    .transformed {
      transform: translate(0, 0);
    }
    
    .indicator {
      position: absolute;
      background-color: red;
      left: 20px;
      top: 70px;
    }
    
    .indicator.two {
      left: 220px;
      top: 120px;
    }

    .indicator.three {
      left: 420px;
      top: 120px;
    }
    
    p {
      margin-top: 150px;
    }
  </style>
  <script type="text/javascript" charset="utf-8">
    window.addEventListener('load', function() {
      window.scrollBy(50, 50);
    }, false);
  </script>
</head>
<body>

  <div class="indicator box"></div>
  <div class="indicator box two"></div>
  <div class="indicator box three"></div>
  <div class="composited box" style="background-color: rgba(0, 0, 255, 0.2)"></div>

  <div class="container">
    <div class="fixed">
    </div>
  </div>

  <div class="container composited two">
    <div class="fixed">
    </div>
  </div>
  
  <div class="container three">
    <div class="transformed box">
      <div class="fixed"></div>
    </div>
  </div>
  
  <p>You should see no red above.</p>

</body>
</html>