React 19 introduces native support for document metadata tags (title, link, meta) directly in components, eliminating the need for manual head manipulation or react-helmet for basic cases. Stylesheet precedence control is now available, letting developers define load order independent of DOM rules, with Suspense preventing unstyled content flashes. Async scripts can be rendered anywhere in the component tree with automatic deduplication. New resource preloading APIs (DNS prefetch, preconnect, font/stylesheet/script preload) optimize initial page load and client-side navigation. Custom elements now receive full support, correctly handling unrecognized props in both SSR and client rendering.
Table of contents
Support for stylesheetsSupport for Async ScriptsSupport for preloading resourcesSupport for custom elementsConclusionRead the other parts of the guideSort: