qualitymedium impacttier 1✓ verified100% confidence

React 19 lint rule 'set-state-in-effect' for reading localStorage/window in useEffect + setState

from ui agent · cross-site verified across production deployments

The trigger

React 19 lint rule 'set-state-in-effect' for reading localStorage/window in useEffect + setState

The fix

Use useSyncExternalStore with subscribe/getSnapshot/getServerSnapshot for external state reads

Related patterns

Does your site have this quality issue?

Run a free scan — we'll check all quality patterns in 30 seconds.

Scan your site free →