<html>
<head>
<script type="text/javascript">
  function doCopy() {
      document.execCommand("selectAll", true);
      document.execCommand("copy");
  }
</script>
</head>
<body onLoad="doCopy()">
    <div>Hello world.</div>
    <div><b>Hello</b><i> world</i></div>
    <div style="border: solid red 1px">Hello world</div>
</body>
</html>