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1/4 One of the most common misconceptions about React Suspense: “Suspense fetches my data.” It doesn’t. Suspense is a coordinator, not a data-fetching library. 🧵👇

shubhra.devReact 19 Suspense Explained: What Actually Happens When a Component SuspendsPart 6 of React 19 Deep Dive: understand Suspense boundaries, nested loading states, streaming SSR, use(), and transitions through practical experiments.

5/10/26, 5:18 am0 reposts0 likes

shubhradev

@shubhra.dev

2/4 Here is what's actually happening: • Something provides a suspension signal (like use() reading a pending Promise or React.lazy()). • Suspense observes this during rendering and decides what to show while waiting.

shubhradev

@shubhra.dev

3/4 This is why putting fetch() inside useEffect() + wrapping in <Suspense> fails to trigger the fallback. useEffect fires post-render. If React can't observe the pending Promise during render, Suspense stays silent.

shubhradev

@shubhra.dev

Want to see how this mechanism actually behaves under the hood? I built practical experiments to demonstrate it step-by-step: shubhra.dev/tutorials/re...