Below is a list of all new features, APIs, and bug fixes.

Read the React 19.3 release post for more information.

New React Features

• <ViewTransition />: Adds <ViewTransition /> and addTransitionType APIs to power View Transition animations in React (@sebmarkbage, @jackpope, @gaearon: #31975, #31987, #31996, #31999, #32001, #32002, #32028, #32029, #32031, #32034, #32038, #32041, #32050, #32090, #32105, #32254, #32379, #32422, #32462, #32540, #32545, #32585, #32599, #32611, #32612, #32617, #32651, #32653, #32656, #32664, #32699, #32723, #32734, #32751, #32752, #32760, #32761, #32764, #32772, #32790, #32819, #32820, #32822, #32833, #32849, #33094, #33191, #33200, #33206, #33293, #33330, #33331, #33332, #33357, #33362, #33433, #33576, #34374, #34450, #34481, #34500, #34502, #34510, #34511, #34539, #35567, #35564, #35485, #35380, #35063, #35060, #34676, #36917, #35337, #35520)

• Fragment Refs: Add Refs to <Fragment /> to support composable platform behavior (@jackpope, @sebmarkbage, @eps1lon, @Dhakshin2007, @chirokas, @teamleaderleo, @fallintoplace: #32465, #32613, #32619, #32654, #32660, #32682, #32722, #32813, #32814, #33056, #33058, #33093, #34069, #34103, #34544, #34545, #37062, #37061, #37060, #36047, #36010, #35642, #35641, #35637, #35630, #34935, #37457, #37408, #37326, #37251, #37171, #37169, #37168, #37167, #37166, #37165, #37164, #37163, #37162, #37161, #37160, #37125, #37063)

New React DOM Features

• browser(): a new react-dom API that returns a usable which errors during server rendering and resolves in the browser. use(browser()) inside a <Suspense> boundary marks a subtree as browser-only without reporting a recoverable error (@gnoff: #37143, #37241)

• Added an onBrowserBailout option to the react-dom/server APIs to observe when a subtree defers to the browser (@gnoff #37193)

Notable changes

• Enable Trusted Types API integration (@rickhanlonii #35816)

• Transitions now render independently instead of being entangled into a single render, so a slow transition no longer holds up unrelated ones (@acdlite #37290)

• Added a DEV-only warning when a component appears to have been unblocked by calling use() conditionally (@hoxyq, @eps1lon: #37104, #37203, #37491)

All Changes

React

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)

React DOM

• Copy source onto the synthetic toggle event (@lazerg #37389)

• Update HTML parser rules for the new <select> parser (@josepharhar #34804)

• Update defaultValue for type="number" inputs to match other input types (@sophiebits #36980)

• Avoid setting innerHTML when it hasn't changed (@sophiebits #36949)

• Forward the nonce option in ReactDOM.preloadModule() (@UditDewan #36851)

• Support fetchPriority for module resources (@TheAlexLichter #36835)

• Track stylesheet preloads when explicitly preloaded to avoid unnecessary suspension (@gnoff #36386)

• Suggest correct casing for the misspelled credentialless iframe attribute (@vmx906 #36322)

• Add credentialless as a recognized boolean attribute for iframes (@vmx906 #36148)

• Prevent reentrant finishedTask from calling completeAll multiple times (@gnoff #36287)

• Update the CSS shorthand property list (@kidonng #35636)

• Support the maskType SVG prop (@sleitor #35921)

• Add support for onFullscreenChange and onFullscreenError events (@chirokas #34621)

• Include submitter in submit events (@eps1lon #35590)

• Fire onReset when automatically resetting forms (@eps1lon #35176)

• Use the FormData submitter parameter (@jenseng #29028)

• Fix form status reset when component state is updated (@eps1lon #34075)

• Batch updates from resize events until the next frame (@eps1lon #35117)

React Server

• 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)

React Server Components

• 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)

This release adds ESLint v10 support, improves performance by skipping compilation for non-React files, and includes compiler lint improvements including better set-state-in-effect detection, improved ref validation, and more helpful error reporting.

Add ESLint v10 support

• Add ESLint v10 support. (@azat-io in #35720)
• Skip compilation for non-React files to improve performance. (@josephsavona in #35589)
• Fix exhaustive deps bug with Flow type casting. (@jorge-cab in #35691)
• Fix useEffectEvent checks in component syntax. (@jbrown215 in #35041)
• Improved set-state-in-effect validation with fewer false negatives. (@jorge-cab in #35134, @josephsavona in #35147, @jackpope in #35214, @chesnokov-tony in #35419, @jsleitor in #36107)
• Improved ref validation for non-mutating functions and event handler props. (@josephsavona in #35893, @kolvian in #35062)
• Compiler now reports all errors instead of stopping at the first. (@josephsavona in #35873–#35884)
• Improved source locations and error display in compiler diagnostics. (@nathanmarks in #35348, @josephsavona in #34963)