react 19.3.0 release notes

semverse.

react 19.3.0 release notes · Semverse

Fast Refresh Fixes
- Fix Fast Refresh to find and remount edits to components wrapped behind lazy() (@sophiebits #36965)
- Fix Fast Refresh so edits to a memo() comparison function take effect (@sophiebits #36964)
- Fix Fast Refresh crash when an edit changes the kind of a component's type (@sophiebits #36963)
- Unify hot reload type resolution for Fast Refresh (@sophiebits #36962)
- Fix Fast Refresh to remount correctly when an edit changes the component kind (@sophiebits #36950)
- Double invoke effects in StrictMode after Fast Refresh (@eps1lon #35962)
Performance Track Fixes
- Prevent crash when accessing $$typeof in Performance Tracks (@eps1lon #35679)
- Handle non-string function names in Performance Tracks (@eps1lon #35659)
- Use minus (-) instead of en dash for removed props in Performance Tracks (@eps1lon #35649)
- Handle arrays with bigints in deep objects in Performance Tracks (@eps1lon #35648)
- Don't enumerate typed array props in Performance Tracks in DEV (@UditDewan #36913)
- Bail out of diffing wide objects and arrays in Performance Tracks (@eps1lon #34742)
- Clear potentially large performance measures in DEV (@hoxyq #34803)
- Fix missing else branch for renders with no props change in Performance Tracks (@hoxyq #34837)
Activity Fixes
- Fix useSyncExternalStore missing store mutations that happened while an Activity tree was hidden (@sophiebits #36947)
- Hide portal contents when an Activity is hidden (@acdlite #35091)
- Prevent metadata hoisting in hidden <Activity> trees (@ronnakamoto #34983)
- Prevent errors thrown inside a hidden Activity from escaping to the visible UI (@acdlite #35074)
- Don't unhide a node if a direct parent Offscreen is still hidden (@sebmarkbage #34821)
- Don't show internal <Offscreen> component in error messages (@rickhanlonii #35763)
Warn in DEV when a component appears to have been unblocked by a conditional use() (@hoxyq, @eps1lon: #37104, #37203, #37491)
Render transitions independently instead of entangling them into a single render (@acdlite #37290)
Fix hang when updating a dehydrated boundary inside a hidden tree (@gaearon #37135)
Don't reacquire Host Singletons during dev effect validation (@gnoff #37113)
Only remove properties from Host Singletons on release (@gnoff #37112)
Don't invoke effects on moved children in StrictMode (@sophiebits #36948)
Throw a clearer error when a rejected Promise is incorrectly instrumented (@eps1lon #36328)
Fix context propagation into Suspense fallbacks (@acdlite #36160)
Fix context propagation through suspended Suspense boundaries (@acdlite #35839)
Fix useDeferredValue getting stuck (@gaearon #36134)
Update useActionState error message to say "action state" instead of "form state" (@rickhanlonii #35790)
Don't warn when rendering data block scripts (@eps1lon #35953)
Treat fibers with alternates as mounted in getNearestMountedFiber (@sebmarkbage #35578)
Always instrument the lazy initializer thenable (@gnoff #35521)
Annotate cascading updates for DevTools performance tracks in DEV (@huntie #34961)
Resolve the .default export of a React.lazy as the canonical value (@sebmarkbage #34906)
Limit owner stacks to 10 frames (@eps1lon #34864)
Ensure useEffectEvent reads latest values in forwardRef and memo() components (@eps1lon #34831)

Add nonce to rendered import maps (@mattcosta7 #37339)
Add an onBrowserBailout option to observe subtrees that defer to the browser (@gnoff #37193)
Stop the caller's signal from retaining a finished render (@unstubbable #37315)
Construct the render lifetime controller only when it is needed (@unstubbable #37357)
Fix react-dom/server hanging on Deno (@fraidev #35235)
Extend stack overflow recovery to retries in SSR (@jackpope #36977)
Fix false-positive hydration mismatch on nonce attributes (@MaxwellCohen #37030)
Guard shell-error callbacks instead of nulling them out on the request (@eps1lon #36916)
Stop firing onAllReady after the shell errored (@eps1lon #36903)
Treat an incomplete tree as an error during error recovery (@acdlite #36911)
Fix non-script modulepreload tracking (@fallintoplace #36564)
Finalize postponed nextSegmentId after the prelude flush (@gaojude #36779)
Preserve referrerPolicy in image preload headers (@ulises-jeremias #36803)
Allow pending work to specialize abort reasons (@gnoff #36586)
Abort tasks that suspend after aborting during render (@gnoff #36585)
Finish abort in a scheduled task (@gnoff #36580)
Fix aborts during resumed rendering (@gnoff #36584)
Track abort state on the request (@gnoff #36583)
Model external work scheduling explicitly in the fb bundle (@gnoff #36576)
Continue reporting aborted task errors after a fatal abort (@gnoff #36575)
Disallow abort reentrancy (@gnoff #36574)
Stop transpiling computed property names (@eps1lon #36542)
Fix crash when capturing the callsite of a stalled use() of a rejected Flight chunk (@lubieowoce #36544)
Double invoke effects in Strict Mode during hydration (@eps1lon #35961)
Add additional task reentrancy protections in Fizz (@gnoff #36291)
Don't outline Suspense boundaries with suspensey CSS during shell flush (@gnoff #35824)
Push a stalled use() to the owner stack and debug task (@eps1lon #35226)
Fix useId tracking on replay (@gnoff #35518)
Correctly handle replaying when hydrating (@gnoff #35494)
Simplify the createSuspenseBoundary path (@sebmarkbage #35087)
Unify preamble-only fields to save a field on Suspense boundaries (@sebmarkbage #35068)
Unify prerender-only fields to save a field on Suspense boundaries (@sebmarkbage #35067)
Push halted awaits to the owner stack for late-arriving I/O info (@unstubbable #35019)
Include all Node.js APIs in the Bun entrypoint for react-dom/server (@RiskyMH #34193)
Detach a Suspense boundary after flushing its segment (@gnoff #34694)

Keep an element pending while a referenced row is resolving (@unstubbable #37542)
Fix RangeError from exponential debug info growth (@unstubbable #37481)
Abort the cache signal when debug objects are retained (@unstubbable #37342)
Transfer key validation of lazy nodes when they are unwrapped (@unstubbable #37258)
Add pending_weak to the Flight thenable protocol (@acdlite #37154)
Outline and dedupe repeated strings (@gaearon #37147)
Port Reply Server traversal guards to the Flight Client (@eps1lon #37144)
Define Flight chunk .then with Object.defineProperty (@eps1lon #37109)
Support Turbopack's experimental array format for chunks (@sampoder #37095)
Limit fake JSX call site stacks to 10 frames (@timneutkens #37086)
Improve performance when decoding Flight replies (@gnoff #37090)
Recognize Node 22+ V8 frames for Promise statics in debug info (@gaearon #36969)
Tailor the warning for binary data serialized through toJSON (Node Buffer) (@unstubbable #36873)
Resolve models before JSON.stringify for faster serialization (@mhart #36795)
Prune debug info when chunks error (@gnoff #36782)
Avoid main-thread stalls from large debug strings (@unstubbable #36570)
Fix stranded row content under Node stream backpressure (@unstubbable #36516)
Fix dropped FormData entries in decodeReplyFromBusboy (@unstubbable #36468)
Harden types and improve performance of Flight replies (@eps1lon #36425)
Add more cycle protections to Flight replies (@eps1lon #36236)
Transport AggregateError.errors (@eps1lon #36156)
Bail out early when a backing entry for Blob deserialization is not a Blob (@eps1lon #36055)
Clear chunk reason after successful module initialization (@unstubbable #36024)
Add support for transporting Error.cause (@eps1lon #35810)
Walk parsed JSON instead of using a reviver for faster RSC payload parsing (@timneutkens #35776)
Skip transferReferencedDebugInfo during debug info resolution (@unstubbable #35795)
Add unstable_allowPartialStream option to Flight Client (@unstubbable #35731)
Fix encodeReply for JSX with temporary references (@unstubbable #35730)
Fix debug channel flag in Node.js renderToPipeableStream (@feedthejim #35724)
Fix stack overflow in visitAsyncNode with deep async chains (@unstubbable #35612)
Allow Server Components to render context providers from client modules (@rickhanlonii #35675)
Allow overriding request.timeOrigin via options.startTime (@lubieowoce #35598)
Warn once if eval is disabled in the dev environment (@eps1lon #35661)
Restore original function name in dev server callstacks served with unsafe-eval (@eps1lon #35650)
Fix react-markup types for server references (@eps1lon #35634)
Add more DoS mitigations to Flight replies and harden Flight (@unstubbable #35632)
Allow cyclic references to be serialized when unwrapping lazy elements (@unstubbable #35471)
Improve cyclic thenable detection in Flight reply server (@cvan20191 #35369)
Add extra loop protection to Flight reply server (@sebmarkbage #35351)
Patch Promise cycles and toString on Server Functions (@sebmarkbage #35345)
Move react-server-dom-webpack/*.unbundled to private react-server-dom-unbundled (@eps1lon #35290)
Never parse then functions in Flight replies (@sebmarkbage #35289)
Patch Flight reply server with fixes from Flight Client (@sebmarkbage #35277)
Complete the list of Node.js internal Promise awaits (@eps1lon #35161)
Reduce risk of maximum call stack exceeded when emitting async sequences (@eps1lon #35159)
Fix pending chunks count for streams and async iterables in DEV (@unstubbable #35143)
Fix broken byte stream parsing caused by buffer detachment (@unstubbable #35127)
Fix hasReadable flag in Node.js clients' debug channel (@unstubbable #35039)
Fix debug info filtering to include later resolved I/O (@unstubbable #35036)
Cache the value when visiting the same I/O or Promise along different paths (@sebmarkbage #35005)
Clone subsequent I/O nodes when resolved more than once (@sebmarkbage #35003)
Fix hang after resolving cyclic references (@unstubbable #34988)
Allow passing DEV-only startTime as an option (@sebmarkbage #34912)
Ignore bound-anonymous-fn resources as they're not considered I/O (@sebmarkbage #34911)
Fix detached ArrayBuffer error when streaming typed arrays (@unstubbable #34849)
Exclude RSC stream if the stream resolves in a task (@sebmarkbage #34838)
Forward the current environment when forwarding I/O entries (@sebmarkbage #34836)
Look for moved debug info when logging component performance track (@sebmarkbage #34839)
Respect displayName of Promise instances on the server (@sebmarkbage #34825)
Avoid unnecessary indirection when serializing debug info (@unstubbable #34797)
Fix preload as attribute for stylesheets (@unstubbable #34760)
Don't serialize toJSON in debug path and omit wide arrays (@sebmarkbage #34759)
Add support for <Activity> (@eps1lon #34697)

react

19.3.0

New React Features

19.3.0

New React Features

New React DOM Features

Notable changes

All Changes

React

React DOM

React Server

React Server Components

19.3.0#

New React Features

19.3.0#

New React Features

New React DOM Features

Notable changes

All Changes

React

React DOM

React Server

React Server Components

19.3.0

19.3.0