I Built a React Suspense Lab: use(), Parallel Boundaries, useTransition & lazy()

"A component suspends and the boundary shows a fallback" sounds abstract until you watch it happen. So I built four live Suspense boundaries you can trigger, each with the code beside it — including the newer use() hook. ▶ Live demo: https://suspense-lab.vercel.app/ Source (React 19): https://github.com/dev48v/suspense-lab When a component reads a not-yet-ready promise, React suspends that subtree and walks up to the nearest to render its fallback. When the promise resolves, React retries the re