Technology·Feb 24, 2026·8 min read
React <Activity /> deep dive: keep state, pause Effects, background render — practical patterns, real edge cases, and rollout checklist
<Activity /> (React 19.2) is the third option between unmounting UI and CSS-hiding it: it preserves state, hides DOM, destroys Effects, and deprioritizes hidden updates. This chapter (part of the React 2026 Primitives guide) focuses on real patterns for tabs/drawers/shell UIs, pre-rendering the next screen, SSR/hydration implications, ecosystem pitfalls, and a production rollout checklist.
