Events like toasts and status messages are visually communicated to GitHub users. Making sure those announcements are read via assistive technology allows users with low or no vision to get that status information.
Always: Announce location changes — Help users understand where they are on a page. Maintain positional awareness.
Always: Announce results of user actions — Give feedback about the success or failure directly following a user action.
Sometimes: Announce other changes — Explore case-by-case when changes are disconnected from the user’s place and the success or failure of the user’s actions. For example:
Distracting change announcements: When other users add issue comments; when presence indicators appear
Essential change announcements: When log lines stream in on the GitHub Actions workflow run page