Closes #???
This change (choose one):
- Breaks existing normative behavior (please add label "breaking")
- Adds new normative requirements
- Adds new normative recommendations or optional items
- Makes only editorial changes (only changes informative sections, or changes normative sections without changing behavior)
- Is a "chore" (metadata, formatting, fixing warnings, etc).
Implementation commitment (delete if not making normative changes):
- Safari (link to issue)
- Chrome (link to issue)
- Firefox (link to issue)
- Edge (public signal)
Commit message:
(Fill in. If making normative changes, describe exactly what the behavioral difference will be.)