<!DOCTYPE html>
<html>
<body>
<style> div { width: 100px; height: 100px; } </style>
<div id="container" style="background: red;">
<div id="host" style="background: blue;"><div id="child">Some content (DOM)</div></div>
</div>
<script>

const slotted = document.querySelector('#slotted');

const shadowRoot = host.attachShadow({mode: 'closed'});
shadowRoot.innerHTML = '<div style="width: 100px; height: 100px; background: green;"><slot></slot></div>';
shadowRoot.querySelector('slot').remove();

document.body.getBoundingClientRect();

child.remove();

document.body.getBoundingClientRect();

</script>
</body>
</html>