g/show_bug.cgi?id=1559961">
  <link rel="match" href="../reference/ref-filled-green-100px-square.xht">

  <style>
  #multicol {
    columns: 2;
    column-fill: auto;
    column-gap: 0;
    height: 400px; /* Must be large enough so that .target doesn't break initially. */
    width: 100px;
    background: red;
  }
  #block {
    height: 25px;
  }
  #target {
    background: green;
    width: 50px;
    height: 200px; /* Expected to be broken into 2 columns after runTest() */
  }
  </style>

  <script>
  func