Add reference target

[dandclark]

Reference Target enables using IDREF attributes such as for and aria-labelledby to refer to elements inside a component's shadow DOM, while maintaining encapsulation of the internal details of the shadow DOM. The main goal of this feature is to enable ARIA to work across shadow root boundaries.

See the reference target explainer.

• At least two implementers are interested (and none opposed):
  • …
  • …
• Tests are written and can be reviewed and commented upon at:
  • …
• Implementation bugs are filed:
  • Chromium: …
  • Gecko: …
  • WebKit: …
  • Deno (only for timers, structured clone, base64 utils, channel messaging, module resolution, web workers, and web storage): …
  • Node.js (only for timers, structured clone, base64 utils, channel messaging, and module resolution): …
• Corresponding HTML AAM & ARIA in HTML issues & PRs:
• MDN issue is filed: …
• The top of this comment includes a clear commit message to use.

(See WHATWG Working Mode: Changes for more details.)

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/common-dom-interfaces.html ( diff )
/common-microsyntaxes.html ( diff )
/dom.html ( diff )
/forms.html ( diff )
/index.html ( diff )
/indices.html ( diff )
/infrastructure.html ( diff )
/parsing.html ( diff )
/popover.html ( diff )
/scripting.html ( diff )