React Native: Performance Optimizations and Bug Fixes

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Good morning. This is your React Native developer briefing for May 28th, 2026.

Today's activity centers on performance optimizations and stability improvements with six notable commits to the main repository.

Pieter De Baets completed a major iOS enhancement by removing the enableMainQueueCoordinatorOnIOS feature flag and making the coordinator implementation permanent. This change eliminates a class of deadlocks by ensuring UI tasks are properly pumped while waiting for JavaScript execution. The rollout has finished successfully, allowing the team to clean up the experimental code paths.

Samuel Susla introduced intelligent image loading prioritization through a new Fabric-based system. Images that are offscreen now automatically downgrade to prefetch priority, while visible images maintain immediate loading priority. This optimization should significantly improve app performance by reducing unnecessary high-priority network requests for content users can't see.

The team also addressed several operational issues. Minh Vu fixed a shell scripting bug in the codegen error logging that was causing script failures instead of properly reporting errors to developers. Danny Povolotski resolved a critical crash on reload that affected ReactCxxPlatform's ReactHost implementation.

Additionally, Susla added a debug overlay for image request priorities to help developers understand when images are using immediate versus prefetch loading, and De Baets cleaned up legacy SurfaceRegistry references that are no longer needed.

What's next: The smart image prefetching feature remains gated behind a feature flag while teams integrate app-specific controls. The main queue coordinator changes are now fully deployed across iOS implementations.

That's your React Native update for today. We'll be back tomorrow with more developer news.