<!DOCTYPE html>
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1606485">
<style>
* {
  grid-template-rows: subgrid;
  display: grid;
  overflow: scroll;
  contain: strict;
}
</style>
<script>
document.addEventListener('DOMContentLoaded', function() {
  let e = document.createElement('s');
  document.documentElement.appendChild(e);
  document.documentElement.getBoundingClientRect() // Update layout
});
</script>
