<html>
<style>
details {
display: inline-block;
background: #eee;
margin: 8px;
}
</style>
<body>
<p>Test to clone details and summary elements. <details> elements in the
second row should be same as elements in the first row.</p>
<hr>
<div class="container">
<details open>
<summary>Summary 1</summary>
Content 1
</details>
<details open>
Content 2
</details>
<details>
<summary>Summary 3</summary>
Content 3
</details>
<details>
Content 4
</details>
</div>
<hr>
<script>
document.body.appendChild(document.querySelector('.container').cloneNode(true));
</script>
</body>
</html>