IIntersectionObserver

Notifies when an element enters/leaves the viewport.

• Wraps: IntersectionObserver
• MDN: Intersection Observer API
• Home: Rask.Core.Browser (all hosts)
• Shape: subscription (pushes to a callback)
• Availability: Web/Server ✅ · PWA/WASM ✅

Inherently DOM — it observes the live document on every host.

See also

• Source: IIntersectionObserver.cs
• Capability matrix
• Browser APIs — the narrative map