Queue popup, modal and notification material geometry and opacity until the matching content buffer commits. Remove event-handler opacity writes that could present material state ahead of content, while preserving compositor dismissal ownership.
Add pending-presentation regression coverage and update the nested shell lifecycle check.
Share window geometry across overview, resize snapshots and retained closes. Advance close handoffs and group retained rendering by stacking position.
Drive shell motion from surface frames, reuse settled widget content, and synchronize notification materials with each card's fade. Replace physical config keys with duration and bounce, and update documentation and regression coverage.