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React 19.2 is now available! This release includes Activity, useEffectEvent, React Performance Tracks, partial pre-rendering, and more: react.dev/blog/2025/10...

useEffectEvent allows you to create "Effect Events" to split “Event” logic out of the Effect that emits it. Similar to DOM events, Effect Events always “see” the latest props and state, so your Effect doesn't need to re-run when the values change. react.dev/learn/separa...

Performance Tracks are a new set of custom tracks in performance profiles that show more info about your React app. They include a Scheduler track that shows the priority of what React is working on, and a Components track to show which component is being worked on. react.dev/reference/de...

Partial pre-rendering is a new capability in React DOM that lets you pre-render part of your app ahead of time, and then resume rendering later to fill in the remaining content. Support includes new APIs to resume from the existing prerender APIs: react.dev/blog/2025/10...

I found some of the limitations put on this a little unexpected, especially the requirement to not pass the callback in props into other components. Well the last time I needed something like useEffectEvent, these limitations would've been no issue, but I wonder if that will generally be the case.

conceptually an Effect Event is like a block of code inside an Effect, kind of like event { … } the API is a bit of like writing the compiled output for that

🐛 the playground is using an older version of React and shows: Error (0, _react.useEffectEvent) is not a function. (In '(0,