LayoutTests/fast/multicol/spanner-inserted-to-multiple-multicolumns.html

<style>
  div {
    column-span: all;
  }
  :nth-last-child(2) {
    float: left;
  }
</style>
<script>
  if (window.testRunner)
    testRunner.dumpAsText();
  onload = () => {
    document.styleSheets[0]?.insertRule(`html { column-width: 1px; }`);
    document.styleSheets[0]?.insertRule(`body { column-width: 1px; }`);
    let n0 = document.createElement('span');
    document.body.appendChild(n0);
    let n1 = document.createElement('div');
    n1.appendChild(document.createElement('div'));
    n0.appendChild(n1);
    n0.appendChild(document.createElement('div'));
    document.body.offsetTop;
    n0.appendChild(document.createElement('div'));
    document.querySelector('style').appendChild(document.createTextNode(''));
  };
</script>

<!--  PASS if no crash or assert -->