<script>
addEventListener("load", () => {
  document.querySelector("ol[contenteditable]").blur();
  document.execCommand("selectAll");
  const targetListItem = document.querySelector("li + li");
  targetListItem.addEventListener("DOMSubtreeModified", () => {
    document.execCommand("forwardDelete");
    document.querySelector("script").appendChild(targetListItem);
  });
  targetListItem.setAttribute("scrolling", "auto");
});
</script>
<ol contenteditable>
<li>
<li>a</li>
