<!DOCTYPE html>
<html>
<style type="text/css">
  #outer {
    width: 100px;
    height: 100px;
    overflow: hidden;
  }

  #clipped {
    clip-path: inset(10px 10px 10px 10px);
    opacity: 0.5;
    width: 200px;
    height: 200px;
  }

  #absolutePosition {
    position: absolute;
    top: 0;
    left: 0;
    width: 400px;
    height: 400px;
    background-color: blue;
  }
</style>

<body style="margin: 0px;">
  <div id="outer">
    <div id="clipped">
      <div id="absolutePosition">
      <!-- This should only be clipped by the clip-path, not by the 100x100
           overflow:hidden clip. -->
      </div>
    </div>
  </div>
  <svg height="0">
    <defs>
      <clipPath id="myClip">
        <rect x="0" y="0" width="100" height="100"/>
        <rect x="100" y="100" width="100" height="100"/>
        <rect x="200" y="200" width="100" height="100"/>
      </clipPath>
    </defs>
  </svg>
</body>
</html>