<!doctype html>
<title>Invalidation works properly across siblings on different slots</title>
<link rel="help" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1794720">
<link rel="match" href="invalidate-sibling-different-slots-ref.html">
<style>
.x { display: table-header-group; }
.x + * { color: green }
</style>
<details open="">
  <summary id="a">Main summary</summary>
  <summary>Should be green</summary>
</details>
<script>
onload = function() {
  let a = document.getElementById("a");
  a.getBounding