Optimizing React Suspense: How Concurrent Mode Handles Data Fetching and Rendering

Short summary

An explainer on how React's Concurrent Mode scheduler handles Suspense for data fetching, and why fallback UI flickers. The scheduler breaks work into prioritized units, showing fallbacks immediately while preparing real content in the background. Tips to reduce flicker include using delayMs/timeoutMs, aggressive caching, smaller Suspense boundaries, and startTransition for low-priority data loading.

• •Concurrent Mode scheduler prioritizes work units, causing fallback flicker during fast loads
• •Suspense boundaries allow incremental content rendering without blocking the entire tree
• •Reduce flicker with caching, smaller boundaries, delayMs, and startTransition

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