  var i = document.getElementById("inner");
        var frag = document.createDocumentFragment();
        var newSpan = document.createElement("span");
        newSpan.appendChild(document.createTextNode("span"));
        newSpan.style.display = "block";
        frag.appendChild(newSpan);
        frag.appendChild(document.createTextNode("after span"));
        i.appendChild(frag);
      }
    </script>
  </head>
  <body onload="doTest()">
    <span id="outermost">
      <span id="outer">
        <span id="i