User story:

As someone responsible for supporting newcomer health, I want clear documentation of the notifications new accounts receive by default, so that I can ensure they are well-timed and not disruptive.

As a QA engineer, I want explicit expectations for when notifications should arrive in production, test, and beta wikis, so that I can verify they are working correctly.

As a Wikimedian, I want transparency about the types and timing of newcomer notifications, so that I understand what newcomers are experiencing and can provide better guidance and support in my community.

Acceptance Criteria:

Clear framework & documentation about Growth-specific newcomer notifications.

Details for each notification:

• What triggers it (e.g., account creation, edit milestone, time-based event)
• Differences in timing across Beta, Test, and production wikis
• Whether the notification is configurable through Community Configuration
• Whether it also triggers an email by default