<html>
<body>
<p>Click the button to create a DETAILS element.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
const x = document.createElement("DETAILS");
let t = document.createTextNode("Some additional details...");
x.appendChild(t);
document.body.appendChild(x);
}
</script>
</body>
</html>