Prevent Hydration Mismatch Without Flickering

When rendering content that depends on client-side storage (localStorage, cookies), avoid both SSR breakage and post-hydration flickering by injecting a synchronous script that updates the DOM before React hydrates.

renderingssrhydrationlocalStorageflicker

Code Comparison

•Incorrect (breaks SSR):tsx

•Incorrect (visual flickering):tsx

•Correct (no flicker, no hydration mismatch):tsx

Why This Matters

Impact: avoids visual flicker and hydration errors. This optimization is classified as MEDIUM priority for production applications.

Hoist Static JSX Elements

Optimize SVG Precision

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