<!DOCTYPE html>
<html>
<body>
File Name: <input type="text" id="filename" value="gamename">.html
<p>Enter file name above.</p>
<button onclick="send()">Try it</button>
<p id="demo"></p>
<script>
function send() {
  var name = document.getElementById("filename").value;
  document.getElementById("demo").innerHTML = name + ".html";
}
</script>
</body>
</html>

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External JavaScript

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