The @w3c ARIA in HTML specification has been updated:
w3.org/TR/html-aria/
These are the authoring rules for using #ARIA when #HTML is the host language.
ARIA in HTML
This specification defines the authoring rules (author conformance requirements) for the use of Accessible Rich Internet Applications (WAI-ARIA) 1.2 and Digital Publishing WAI-ARIA Module 1.0 attributes on [HTML] elements.www.w3.org