sfnext-performance

Keep a Storefront Next storefront fast and self-review changes for performance: LCP, CLS and TBT, Suspense placement and granularity, stable promise identity, lazy-loaded modals and drawers with useDeferredUnmount, useDeferredRender, Region critical, DynamicImage and image priority, font loading, resource hints (links.preconnect), bundle size checks (pnpm bundlesize, BUNDLES_SIZE_ANALYZE), Lighthouse CI, and the performance.metrics / Server-Timing flags. Use for "page is slow", "LCP regression", "skeleton flashes", "bundle too big", "review my diff for performance", "hydration mismatch or extra re-renders", "waterfall of fetches", or before merging feature work that adds loaders, fetchers, modals and drawers or images. Do not use for loader/action mechanics (use storefront-next:sfnext-data-fetching), revalidation policy (use storefront-next:sfnext-revalidation), or accessibility (use storefront-next:sfnext-accessibility).