chromium/content/test/data/accessibility/aria/aria-owns-with-role-change.html

<!--
@WAIT-FOR:region
@AURALINUX-ALLOW:xml-roles*
@WIN-ALLOW:xml-roles*
@MAC-ALLOW:AXRoleDescription*
@UIA-WIN-ALLOW:LocalizedControlType*
-->
<div id="owner" role="doc-glossary" aria-owns="owned" aria-label="Stuff">
  Text
</div>
<div id="owned" role="button">Button</div>

<script>
document.addEventListener('DOMContentLoaded', () => {
  setTimeout(() => {
    document.getElementById('owner').role = 'doc-toc';
    document.getElementById('owner').role = 'region';
  }, 50);
});
</script>