Selective hydration

React chapter 111 · patterns.dev · Selective Hydration · source: https://www.patterns.dev/react/react-selective-hydration

The problem

HTML streamed (109) but hydration is still one queue: Comments’ 2s JS blocks the already-visible Nav button. The user clicks Nav and nothing happens until Comments finishes.

The pattern that fixes it

Each Suspense boundary hydrates independently. A click inside a not-yet-hydrated region jumps that region to the front of the queue. hydrateRoot + streaming — not renderToString. loading.tsx (34) is the boundary Next inserts for you.

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