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<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>childElementCount live</title>
</head>
<body>
  <pre id="out"></pre>
  <script>
    var list = document.createElement("ul");
    document.body.insertBefore(list, document.getElementById("out"));
    var lines = [];
    lines.push(String(list.childElementCount));
    var item = document.createElement("li");
    item.textContent = "One";
    list.appendChild(item);
    lines.push(String(list.childElementCount));
    document.getElementById("out").textContent = lines.join("\n");
  </script>
</body>
</html>

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