<!DOCTYPE html>
<html>
<head>
  <style>
    div {
      display: inline-block;
      width: 200px;
      height: 100px;
      background-image: repeating-linear-gradient(red 10%, green 10%, green 30%);
    }

    .ref {
      background-image: repeating-linear-gradient(green 10%, green 30%);
    }
  </style>
  <script>
    if (window.testRunner) {
      var dumpPixels = true;
      testRunner.dumpAsText(dumpPixels);
    }
  </script>
</head>
<body>

  <!-- You should see two green rectangles, with no red. -->
  <div></div>
  <div class="ref"></div>

</body>
</html>