<script>
function go() {
  a.appendChild(c)
  a.getRootNode().addEventListener("DOMSubtreeModified", eh, { once: true })
  b.setAttribute("oninvalid", "eh()")
}
function eh() {
  b.setAttribute("role", "dialog")
  window.scrollBy(0.802, 0.384)
  var x = document.getSelection()
  x.extend(a)
  x.modify("move", "forward", "lineboundary")
  a.style.setProperty("column-span", "all")
}
</script>
<body onload=go()>
<select>
<option id="a" contenteditable="true">x</span>
<input id="b">
<textarea id="c">