valdrinkoshi/stacking-context-scroll.html

## stacking-context-scroll.html
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
  <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1, user-scalable=yes">

  <title>Stacking context causes scroll</title>

  <style>
    .container {
      border: 1px solid gray;
      height: 200px;
      overflow: auto;
      /* creates a new stacking context */
      transform: translateZ(0);
    }
    .tall {
      background-color: orange;
      height: 900px;
    }

    .fixed {
      position: fixed;
      padding: 20px;
      top: 50%;
      left: 50%;
      background-color: yellow;
      z-index: 9999;
    }
  </style>
</head>
<body>

  <div class="container">
    <div class="fixed">
      I should not scroll!
    </div>
    <div class="tall"></div>
  </div>

</body>
</html>