<!doctype html>
<html>
<head>
<meta charset="utf-8">
<script>
addEventListener("load", () => {
  const textarea = document.querySelector("textarea");
  const ul = document.createElement('ul');

  const textNodeInTextarea = document.createTextNode("");
  textarea.appendChild(textNodeInTextarea);
  document.documentElement.getBoundingClientRect();

  textarea.appendChild(ul);
  const range = document.createRange();
  range.selectNode(ul);

  textNodeInTextarea.data = "ab";
  textNodeInTextarea.splitText(1);
});
</script>
</head>
<body><textarea></textarea></body>
</html>
