@ -85,11 +85,12 @@ Most React developers will not interact with React's offscreen APIs directly. In
The idea is that you should be able to render any React tree offscreen without changing the way you write your components. When a component is rendered offscreen, it does not actually *mount* until the component becomes visible — its effects are not fired. For example, if a component uses `useEffect` to log analytics when it appears for the first time, prerendering won't mess up the accuracy of those analytics. Similarly, when a component goes offscreen, its effects are unmounted, too. A key feature of offscreen rendering is that you can toggle the visibility of a component without losing its state.
Since our last update, we've tested an experimental version of prerendering internally at Meta in our React Native apps on Android and iOS, with positive performance results. We've also improved how offscreen rendering works with Suspense — suspending inside a offscreen tree will not trigger Suspense fallbacks. Our remaining work involves finalizing the primitives that are exposed to library developers. We expect to publish an RFC later this year, alongside an experimental API for testing and feedback.
Since our last update, we've tested an experimental version of prerendering internally at Meta in our React Native apps on Android and iOS, with positive performance results. We've also improved how offscreen rendering works with Suspense — suspending inside an offscreen tree will not trigger Suspense fallbacks. Our remaining work involves finalizing the primitives that are exposed to library developers. We expect to publish an RFC later this year, alongside an experimental API for testing and feedback.
## Transition Tracing {/*transition-tracing*/}
The Transition Tracing API lets you detect when React transitions become slower and to investigate why they may be slow. Following our last update, we have completed the initial design of the API and published an [RFC](https://github.com/reactjs/rfcs/pull/238). The basic capabilities have also been implemented. The project is currently on hold. We welcome feedback on the RFC and look forward to resuming its development to provide a better performance measurement tool for React transitions.
The Transition Tracing API lets you detect when [React Transitions](/reference/react/useTransition) become slower and to investigate why they may be slow. Following our last update, we have completed the initial design of the API and published an [RFC](https://github.com/reactjs/rfcs/pull/238). The basic capabilities have also been implemented. The project is currently on hold. We welcome feedback on the RFC and look forward to resuming its development to provide a better performance measurement tool for React. This will be particularly useful with routers built on top of React Transitions, like the [Next.js App Router](/learn/start-a-new-react-project#nextjs-app-router).
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In addition to this update, our team has made recent guest appearances on community podcasts and livestreams to speak more on our work and answer questions.