npm / react-dom

react-dom

What changed in react-dom 19, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-18.

4 security8 new APIs and options4 performance3 behavior and defaults15 fixes and other

See which of these apply to your code, ranked, in your agent:

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react-dom 1934 changes

Adds nonce to rendered import maps.
19.3.0release notes
Enables integration with the Trusted Types API.
19.3.0release notes
Added more DoS mitigations to Server Actions.
19.0.4, 19.1.5, 19.2.4release notes release notes release notes
Server Components were hardened.
19.0.4, 19.1.5, 19.2.4release notes release notes release notes

Adds a react-dom API that resolves in the browser and errors during server rendering; use it inside a Suspense boundary to mark a subtree as browser-only without a recoverable error.
19.3.0release notes
Recognizes credentialless as a boolean iframe attribute.
19.3.0release notes
Adds fetchPriority support for module resources.
19.3.0release notes
Adds support for the maskType SVG prop.
19.3.0release notes
Adds an option to react-dom/server APIs for observing when a subtree defers to the browser.
19.3.0release notes
Adds an option for observing subtrees that defer to the browser.
19.3.0release notes
Adds support for the onFullscreenChange event.
19.3.0release notes
Adds support for the onFullscreenError event.
19.3.0release notes

Avoids setting innerHTML when its value has not changed.
19.3.0release notes
Batches updates from resize events until the next frame.
19.3.0release notes
Tracks explicitly preloaded stylesheets to avoid unnecessary suspension.
19.3.0release notes
Performance improvements were made to React Server Components.
19.0.6, 19.2.6release notes release notes

Submit events now include submitter, and FormData uses its submitter parameter.
19.3.0release notes
Transitions render independently instead of being entangled into one render, so a slow transition no longer holds up unrelated ones.
19.3.0release notes
Type hardening may affect type checking when using React Server Components.
19.0.6release notes

For type="number" inputs, defaultValue now matches the behavior of other input types.
19.3.0release notes
Preserves referrerPolicy in image preload headers.
19.3.0release notes
Fixes false-positive hydration mismatches on nonce attributes.
19.3.0release notes
Stops firing onAllReady after the shell has errored.
19.3.0release notes
Fires onReset when forms are automatically reset.
19.3.0release notes
Fixes a hang in react-dom/server on Deno.
19.3.0release notes
Forwards the nonce option when preloading a module.
19.3.0release notes
Updates HTML parser rules for the new select parser.
19.3.0release notes
The synthetic toggle event now includes source.
19.3.0release notes
Fixed missing FormData entries in Server Actions that regressed in 19.2.6.
19.0.7, 19.1.8, 19.2.7release notes release notes release notes
React Server Components add more cycle protections.
19.0.5, 19.1.6, 19.2.5release notes release notes release notes
Extra loop protection was added to React Server Functions.
19.0.3, 19.1.4, 19.2.3release notes release notes release notes
Patched Promise cycles involving Server Functions.
19.0.2, 19.1.3, 19.2.2release notes release notes release notes
React Server Component fixes were brought to Server Actions.
19.0.1, 19.1.2, 19.2.1release notes release notes release notes
Patched toString behavior on Server Functions.
19.1.3release notes