caption-insert-in-first-line-1.html

Enable keyboard shortcuts

<!DOCTYPE html>

<style>

  div { color: red; }

  div::first-line { color: green }

  #table { display: inline-table; }

  #caption { display: table-caption; }

  #tbody { display: table-row-group; }

</style>

<div id="x">

  <span id="table">

    <span id="tbody">be green</span>

  </span>

</div>

<script>

  x.offsetWidth;

  var caption = document.createElement("span");

  caption.id = "caption";

  caption.textContent = "This should";

  table.appendChild(caption);

</script>