Skip to content

Ensure dispatch from useFormState works in StrictMode #28557

New issue

Have a question about this project? # for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “#”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? # to your account

Merged
merged 3 commits into from
Mar 20, 2024

Conversation

eps1lon
Copy link
Collaborator

@eps1lon eps1lon commented Mar 14, 2024

Summary

Closes #28556

We didn't follow the Rules of Hooks in the rerender implementation for mounts.

Test plan

  • Added test based on "useFormState updates state asynchronously and queues multiple actions" but with StrictMode and less dispatches (because it repros on the first attempt)

@facebook-github-bot facebook-github-bot added CLA Signed React Core Team Opened by a member of the React Core Team labels Mar 14, 2024
@react-sizebot
Copy link

react-sizebot commented Mar 14, 2024

Comparing: bbc571a...e32f38a

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name +/- Base Current +/- gzip Base gzip Current gzip
oss-stable/react-dom/cjs/react-dom.production.min.js = 176.83 kB 176.84 kB +0.02% 54.91 kB 54.92 kB
oss-experimental/react-dom/cjs/react-dom.production.min.js = 173.55 kB 173.55 kB = 54.11 kB 54.11 kB
facebook-www/ReactDOM-prod.classic.js = 594.04 kB 594.07 kB = 104.37 kB 104.38 kB
facebook-www/ReactDOM-prod.modern.js = 577.30 kB 577.33 kB = 101.42 kB 101.43 kB
test_utils/ReactAllWarnings.js Deleted 66.87 kB 0.00 kB Deleted 16.36 kB 0.00 kB

Significant size changes

Includes any change greater than 0.2%:

Expand to show
Name +/- Base Current +/- gzip Base gzip Current gzip
test_utils/ReactAllWarnings.js Deleted 66.87 kB 0.00 kB Deleted 16.36 kB 0.00 kB

Generated by 🚫 dangerJS against e32f38a

@eps1lon eps1lon changed the title Failing test for null dispatch returned from useFormState in StrictMode Ensure dispatch in useFormState works in StrictMode Mar 14, 2024
@eps1lon eps1lon force-pushed the strictmode-useformstate branch from f792c17 to 1c4e7c4 Compare March 14, 2024 10:20
@eps1lon eps1lon force-pushed the strictmode-useformstate branch from 1c4e7c4 to 9b3f1f3 Compare March 14, 2024 10:21
@eps1lon eps1lon marked this pull request as ready for review March 14, 2024 10:25
@eps1lon eps1lon requested a review from acdlite March 14, 2024 10:26
@eps1lon eps1lon changed the title Ensure dispatch in useFormState works in StrictMode Ensure dispatch from useFormState works in StrictMode Mar 14, 2024
@@ -2259,6 +2259,9 @@ function rerenderFormState<S, P>(
);
}

// For mount, pending is always false.
const [isPending] = rerenderState(false);
Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Since we don't actually need the result, all we need to do is advance the hook list.

Suggested change
const [isPending] = rerenderState(false);
updateWorkInProgressHook();

Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Feels a bit brittle but you know this part better than I do.

Copy link
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I consider this pretty low level code so I think it's fine. I care more about not observing the value of isPending since it causes a bunch of redundant read operations.

@acdlite
Copy link
Collaborator

acdlite commented Mar 19, 2024

This was introduced by #28514. Easy oversight to make, glad we caught it quickly.

Note that it doesn't just affect StrictMode, the same issue happen if you called setState during render to trigger a re-render. Or if you suspended with use after useFormState has already been called. That last one is the most idiomatic so I'd probably write the regression test using that pattern.

Co-Authored-By: Andrew Clark <git@andrewclark.io>
@eps1lon eps1lon requested a review from acdlite March 19, 2024 18:34
@eps1lon eps1lon merged commit 8ef14cf into facebook:main Mar 20, 2024
@eps1lon eps1lon deleted the strictmode-useformstate branch March 20, 2024 15:16
github-actions bot pushed a commit that referenced this pull request Mar 20, 2024
Co-authored-by: Andrew Clark <git@andrewclark.io>

DiffTrain build for [8ef14cf](8ef14cf)
gnoff added a commit to gnoff/next.js that referenced this pull request Mar 25, 2024
- facebook/react#28596
- facebook/react#28625
- facebook/react#28616
- facebook/react#28491
- facebook/react#28583
- facebook/react#28427
- facebook/react#28613
- facebook/react#28599
- facebook/react#28611
- facebook/react#28610
- facebook/react#28606
- facebook/react#28598
- facebook/react#28549
- facebook/react#28557
- facebook/react#28467
- facebook/react#28591
- facebook/react#28459
- facebook/react#28590
- facebook/react#28564
- facebook/react#28582
- facebook/react#28579
- facebook/react#28578
- facebook/react#28521
- facebook/react#28550
- facebook/react#28576
- facebook/react#28577
- facebook/react#28571
- facebook/react#28572
- facebook/react#28560
- facebook/react#28569
- facebook/react#28573
- facebook/react#28546
- facebook/react#28568
- facebook/react#28562
- facebook/react#28566
- facebook/react#28565
- facebook/react#28559
- facebook/react#28508
- facebook/react#20432
- facebook/react#28555
- facebook/react#24730
- facebook/react#28472
- facebook/react#27991
- facebook/react#28514
- facebook/react#28548
- facebook/react#28526
- facebook/react#28515
- facebook/react#28533
- facebook/react#28532
- facebook/react#28531
- facebook/react#28407
- facebook/react#28522
- facebook/react#28538
- facebook/react#28509
- facebook/react#28534
- facebook/react#28527
- facebook/react#28528
- facebook/react#28519
- facebook/react#28411
- facebook/react#28520
- facebook/react#28518
- facebook/react#28493
- facebook/react#28504
- facebook/react#28499
- facebook/react#28501
- facebook/react#28496
- facebook/react#28471
- facebook/react#28351
- facebook/react#28486
- facebook/react#28490
- facebook/react#28488
- facebook/react#28468
- facebook/react#28321
- facebook/react#28477
- facebook/react#28479
- facebook/react#28480
- facebook/react#28478
- facebook/react#28464
- facebook/react#28475
- facebook/react#28456
- facebook/react#28319
- facebook/react#28345
- facebook/react#28337
- facebook/react#28335
- facebook/react#28466
- facebook/react#28462
- facebook/react#28322
- facebook/react#28444
- facebook/react#28448
- facebook/react#28449
- facebook/react#28446
- facebook/react#28447
- facebook/react#24580
- facebook/react#28514
- facebook/react#28548
- facebook/react#28526
- facebook/react#28515
- facebook/react#28533
- facebook/react#28532
- facebook/react#28531
- facebook/react#28407
- facebook/react#28522
- facebook/react#28538
- facebook/react#28509
- facebook/react#28534
- facebook/react#28527
- facebook/react#28528
- facebook/react#28519
- facebook/react#28411
- facebook/react#28520
- facebook/react#28518
- facebook/react#28493
- facebook/react#28504
- facebook/react#28499
- facebook/react#28501
- facebook/react#28496
- facebook/react#28471
- facebook/react#28351
- facebook/react#28486
- facebook/react#28490
- facebook/react#28488
- facebook/react#28468
- facebook/react#28321
- facebook/react#28477
- facebook/react#28479
- facebook/react#28480
- facebook/react#28478
- facebook/react#28464
- facebook/react#28475
- facebook/react#28456
- facebook/react#28319
- facebook/react#28345
- facebook/react#28337
- facebook/react#28335
- facebook/react#28466
- facebook/react#28462
- facebook/react#28322
- facebook/react#28444
- facebook/react#28448
- facebook/react#28449
- facebook/react#28446
- facebook/react#28447
- facebook/react#24580
gnoff added a commit to gnoff/next.js that referenced this pull request Mar 25, 2024
- facebook/react#28596
- facebook/react#28625
- facebook/react#28616
- facebook/react#28491
- facebook/react#28583
- facebook/react#28427
- facebook/react#28613
- facebook/react#28599
- facebook/react#28611
- facebook/react#28610
- facebook/react#28606
- facebook/react#28598
- facebook/react#28549
- facebook/react#28557
- facebook/react#28467
- facebook/react#28591
- facebook/react#28459
- facebook/react#28590
- facebook/react#28564
- facebook/react#28582
- facebook/react#28579
- facebook/react#28578
- facebook/react#28521
- facebook/react#28550
- facebook/react#28576
- facebook/react#28577
- facebook/react#28571
- facebook/react#28572
- facebook/react#28560
- facebook/react#28569
- facebook/react#28573
- facebook/react#28546
- facebook/react#28568
- facebook/react#28562
- facebook/react#28566
- facebook/react#28565
- facebook/react#28559
- facebook/react#28508
- facebook/react#20432
- facebook/react#28555
- facebook/react#24730
- facebook/react#28472
- facebook/react#27991
- facebook/react#28514
- facebook/react#28548
- facebook/react#28526
- facebook/react#28515
- facebook/react#28533
- facebook/react#28532
- facebook/react#28531
- facebook/react#28407
- facebook/react#28522
- facebook/react#28538
- facebook/react#28509
- facebook/react#28534
- facebook/react#28527
- facebook/react#28528
- facebook/react#28519
- facebook/react#28411
- facebook/react#28520
- facebook/react#28518
- facebook/react#28493
- facebook/react#28504
- facebook/react#28499
- facebook/react#28501
- facebook/react#28496
- facebook/react#28471
- facebook/react#28351
- facebook/react#28486
- facebook/react#28490
- facebook/react#28488
- facebook/react#28468
- facebook/react#28321
- facebook/react#28477
- facebook/react#28479
- facebook/react#28480
- facebook/react#28478
- facebook/react#28464
- facebook/react#28475
- facebook/react#28456
- facebook/react#28319
- facebook/react#28345
- facebook/react#28337
- facebook/react#28335
- facebook/react#28466
- facebook/react#28462
- facebook/react#28322
- facebook/react#28444
- facebook/react#28448
- facebook/react#28449
- facebook/react#28446
- facebook/react#28447
- facebook/react#24580
EdisonVan pushed a commit to EdisonVan/react that referenced this pull request Apr 15, 2024
…8557)

Co-authored-by: Andrew Clark <git@andrewclark.io>
bigfootjon pushed a commit that referenced this pull request Apr 18, 2024
Co-authored-by: Andrew Clark <git@andrewclark.io>

DiffTrain build for commit 8ef14cf.
eps1lon added a commit to vercel/next.js that referenced this pull request Apr 19, 2024
### React upstream changes

- facebook/react#28643
- facebook/react#28628
- facebook/react#28361
- facebook/react#28513
- facebook/react#28299
- facebook/react#28617
- facebook/react#28618
- facebook/react#28621
- facebook/react#28614
- facebook/react#28596
- facebook/react#28625
- facebook/react#28616
- facebook/react#28491
- facebook/react#28583
- facebook/react#28427
- facebook/react#28613
- facebook/react#28599
- facebook/react#28611
- facebook/react#28610
- facebook/react#28606
- facebook/react#28598
- facebook/react#28549
- facebook/react#28557
- facebook/react#28467
- facebook/react#28591
- facebook/react#28459
- facebook/react#28590
- facebook/react#28564
- facebook/react#28582
- facebook/react#28579
- facebook/react#28578
- facebook/react#28521
- facebook/react#28550
- facebook/react#28576
- facebook/react#28577
- facebook/react#28571
- facebook/react#28572
- facebook/react#28560
- facebook/react#28569
- facebook/react#28573
- facebook/react#28546
- facebook/react#28568
- facebook/react#28562
- facebook/react#28566
- facebook/react#28565
- facebook/react#28559
- facebook/react#28508
- facebook/react#20432
- facebook/react#28555
- facebook/react#24730
- facebook/react#28472
- facebook/react#27991
- facebook/react#28514
- facebook/react#28548
- facebook/react#28526
- facebook/react#28515
- facebook/react#28533
- facebook/react#28532
- facebook/react#28531
- facebook/react#28407
- facebook/react#28522
- facebook/react#28538
- facebook/react#28509
- facebook/react#28534
- facebook/react#28527
- facebook/react#28528
- facebook/react#28519
- facebook/react#28411
- facebook/react#28520
- facebook/react#28518
- facebook/react#28493
- facebook/react#28504
- facebook/react#28499
- facebook/react#28501
- facebook/react#28496
- facebook/react#28471
- facebook/react#28351
- facebook/react#28486
- facebook/react#28490
- facebook/react#28488
- facebook/react#28468
- facebook/react#28321
- facebook/react#28477
- facebook/react#28479
- facebook/react#28480
- facebook/react#28478
- facebook/react#28464
- facebook/react#28475
- facebook/react#28456
- facebook/react#28319
- facebook/react#28345
- facebook/react#28337
- facebook/react#28335
- facebook/react#28466
- facebook/react#28462
- facebook/react#28322
- facebook/react#28444
- facebook/react#28448
- facebook/react#28449
- facebook/react#28446
- facebook/react#28447
- facebook/react#24580
- facebook/react#28514
- facebook/react#28548
- facebook/react#28526
- facebook/react#28515
- facebook/react#28533
- facebook/react#28532
- facebook/react#28531
- facebook/react#28407
- facebook/react#28522
- facebook/react#28538
- facebook/react#28509
- facebook/react#28534
- facebook/react#28527
- facebook/react#28528
- facebook/react#28519
- facebook/react#28411
- facebook/react#28520
- facebook/react#28518
- facebook/react#28493
- facebook/react#28504
- facebook/react#28499
- facebook/react#28501
- facebook/react#28496
- facebook/react#28471
- facebook/react#28351
- facebook/react#28486
- facebook/react#28490
- facebook/react#28488
- facebook/react#28468
- facebook/react#28321
- facebook/react#28477
- facebook/react#28479
- facebook/react#28480
- facebook/react#28478
- facebook/react#28464
- facebook/react#28475
- facebook/react#28456
- facebook/react#28319
- facebook/react#28345
- facebook/react#28337
- facebook/react#28335
- facebook/react#28466
- facebook/react#28462
- facebook/react#28322
- facebook/react#28444
- facebook/react#28448
- facebook/react#28449
- facebook/react#28446
- facebook/react#28447
- facebook/react#24580
henriettelienrebnor pushed a commit to equinor/Dexpi2Imf that referenced this pull request Apr 23, 2025
![snyk-top-banner](https://res.cloudinary.com/snyk/image/upload/r-d/scm-platform/snyk-pull-requests/pr-banner-default.svg)


<h3>Snyk has created this PR to upgrade react from 19.0.0 to
19.1.0.</h3>

:information_source: Keep your dependencies up-to-date. This makes it
easier to fix existing vulnerabilities and to more quickly identify and
fix newly disclosed vulnerabilities when they affect your project.

<hr/>


- The recommended version is **78 versions** ahead of your current
version.

- The recommended version was released **22 days ago**.



<details>
<summary><b>Release notes</b></summary>
<br/>
  <details>
    <summary>Package name: <b>react</b></summary>
    <ul>
      <li>
<b>19.1.0</b> - <a
href="https://github.com/facebook/react/releases/tag/v19.1.0">2025-03-28</a></br><h3>Owner
Stack</h3>
<p>An Owner Stack is a string representing the components that are
directly responsible for rendering a particular component. You can log
Owner Stacks when debugging or use Owner Stacks to enhance error
overlays or other development tools. Owner Stacks are only available in
development builds. Component Stacks in production are unchanged.</p>
<ul>
<li>An Owner Stack is a development-only stack trace that helps identify
which components are responsible for rendering a particular component.
An Owner Stack is distinct from a Component Stacks, which shows the
hierarchy of components leading to an error.</li>
<li>The <a href="https://react.dev/reference/react/captureOwnerStack"
rel="nofollow">captureOwnerStack API</a> is only available in
development mode and returns a Owner Stack, if available. The API can be
used to enhance error overlays or log component relationships when
debugging. <a
href="https://github.com/facebook/react/pull/29923"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29923/hovercard">#29923</a>, <a
href="https://github.com/facebook/react/pull/32353"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32353/hovercard">#32353</a>, <a
href="https://github.com/facebook/react/pull/30306"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30306/hovercard">#30306</a>,<br>
<a href="https://github.com/facebook/react/pull/32538"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32538/hovercard">#32538</a>, <a
href="https://github.com/facebook/react/pull/32529"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32529/hovercard">#32529</a>, <a
href="https://github.com/facebook/react/pull/32538"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32538/hovercard">#32538</a></li>
</ul>
<h3>React</h3>
<ul>
<li>Enhanced support for Suspense boundaries to be used anywhere,
including the client, server, and during hydration. <a
href="https://github.com/facebook/react/pull/32069"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32069/hovercard">#32069</a>, <a
href="https://github.com/facebook/react/pull/32163"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32163/hovercard">#32163</a>, <a
href="https://github.com/facebook/react/pull/32224"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32224/hovercard">#32224</a>, <a
href="https://github.com/facebook/react/pull/32252"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32252/hovercard">#32252</a></li>
<li>Reduced unnecessary client rendering through improved hydration
scheduling <a
href="https://github.com/facebook/react/pull/31751"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31751/hovercard">#31751</a></li>
<li>Increased priority of client rendered Suspense boundaries <a
href="https://github.com/facebook/react/pull/31776"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31776/hovercard">#31776</a></li>
<li>Fixed frozen fallback states by rendering unfinished Suspense
boundaries on the client. <a
href="https://github.com/facebook/react/pull/31620"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31620/hovercard">#31620</a></li>
<li>Reduced garbage collection pressure by improving Suspense boundary
retries. <a href="https://github.com/facebook/react/pull/31667"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31667/hovercard">#31667</a></li>
<li>Fixed erroneous “Waiting for Paint” log when the passive effect
phase was not delayed <a
href="https://github.com/facebook/react/pull/31526"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31526/hovercard">#31526</a></li>
<li>Fixed a regression causing key warnings for flattened positional
children in development mode. <a
href="https://github.com/facebook/react/pull/32117"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32117/hovercard">#32117</a></li>
<li>Updated <code>useId</code> to use valid CSS selectors, changing
format from <code>:r123:</code> to <code>«r123»</code>. <a
href="https://github.com/facebook/react/pull/32001"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32001/hovercard">#32001</a></li>
<li>Added a dev-only warning for null/undefined created in useEffect,
useInsertionEffect, and useLayoutEffect. <a
href="https://github.com/facebook/react/pull/32355"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32355/hovercard">#32355</a></li>
<li>Fixed a bug where dev-only methods were exported in production
builds. React.act is no longer available in production builds. <a
href="https://github.com/facebook/react/pull/32200"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32200/hovercard">#32200</a></li>
<li>Improved consistency across prod and dev to improve compatibility
with Google Closure Complier and bindings <a
href="https://github.com/facebook/react/pull/31808"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31808/hovercard">#31808</a></li>
<li>Improve passive effect scheduling for consistent task yielding. <a
href="https://github.com/facebook/react/pull/31785"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31785/hovercard">#31785</a></li>
<li>Fixed asserts in React Native when
passChildrenWhenCloningPersistedNodes is enabled for OffscreenComponent
rendering. <a
href="https://github.com/facebook/react/pull/32528"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32528/hovercard">#32528</a></li>
<li>Fixed component name resolution for Portal <a
href="https://github.com/facebook/react/pull/32640"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32640/hovercard">#32640</a></li>
<li>Added support for beforetoggle and toggle events on the dialog
element. <a class="issue-link js-issue-link" data-error-text="Failed to
load title" data-id="2882132160" data-permission-text="Title is private"
data-url="https://github.com/facebook/react/issues/32479"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32479/hovercard"
href="https://github.com/facebook/react/pull/32479">#32479</a>
<a href="https://github.com/facebook/react/pull/32479"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32479/hovercard">#32479</a></li>
</ul>
<h3>React DOM</h3>
<ul>
<li>Fixed double warning when the <code>href</code> attribute is an
empty string <a
href="https://github.com/facebook/react/pull/31783"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31783/hovercard">#31783</a></li>
<li>Fixed an edge case where <code>getHoistableRoot()</code> didn’t work
properly when the container was a Document <a
href="https://github.com/facebook/react/pull/32321"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32321/hovercard">#32321</a></li>
<li>Removed support for using HTML comments (e.g. <code>&lt;!--
--&gt;</code>) as a DOM container. <a
href="https://github.com/facebook/react/pull/32250"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32250/hovercard">#32250</a></li>
<li>Added support for <code>&lt;script&gt;</code> and
<code>&lt;template&gt;</code> tags to be nested within
<code>&lt;select&gt;</code> tags. <a
href="https://github.com/facebook/react/pull/31837"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31837/hovercard">#31837</a></li>
<li>Fixed responsive images to be preloaded as HTML instead of headers
<a href="https://github.com/facebook/react/pull/32445"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32445/hovercard">#32445</a></li>
</ul>
<h3>use-sync-external-store</h3>
<ul>
<li>Added <code>exports</code> field to <code>package.json</code> for
<code>use-sync-external-store</code> to support various entrypoints. <a
href="https://github.com/facebook/react/pull/25231"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25231/hovercard">#25231</a></li>
</ul>
<h3>React Server Components</h3>
<ul>
<li>Added <code>unstable_prerender</code>, a new experimental API for
prerendering React Server Components on the server <a
href="https://github.com/facebook/react/pull/31724"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31724/hovercard">#31724</a></li>
<li>Fixed an issue where streams would hang when receiving new chunks
after a global error <a
href="https://github.com/facebook/react/pull/31840"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31840/hovercard">#31840</a>, <a
href="https://github.com/facebook/react/pull/31851"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31851/hovercard">#31851</a></li>
<li>Fixed an issue where pending chunks were counted twice. <a
href="https://github.com/facebook/react/pull/31833"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31833/hovercard">#31833</a></li>
<li>Added support for streaming in edge environments <a
href="https://github.com/facebook/react/pull/31852"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31852/hovercard">#31852</a></li>
<li>Added support for sending custom error names from a server so that
they are available in the client for console replaying. <a
href="https://github.com/facebook/react/pull/32116"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32116/hovercard">#32116</a></li>
<li>Updated the server component wire format to remove IDs for hints and
console.log because they have no return value <a
href="https://github.com/facebook/react/pull/31671"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31671/hovercard">#31671</a></li>
<li>Exposed <code>registerServerReference</code> in client builds to
handle server references in different environments. <a
href="https://github.com/facebook/react/pull/32534"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32534/hovercard">#32534</a></li>
<li>Added react-server-dom-parcel package which integrates Server
Components with the <a href="https://parceljs.org/"
rel="nofollow">Parcel bundler</a> <a
href="https://github.com/facebook/react/pull/31725"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31725/hovercard">#31725</a>, <a
href="https://github.com/facebook/react/pull/32132"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32132/hovercard">#32132</a>, <a
href="https://github.com/facebook/react/pull/31799"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31799/hovercard">#31799</a>, <a
href="https://github.com/facebook/react/pull/32294"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/32294/hovercard">#32294</a>, <a
href="https://github.com/facebook/react/pull/31741"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31741/hovercard">#31741</a></li>
</ul>
      </li>
      <li>
        <b>19.1.0-canary-ff628334-20250205</b> - 2025-02-06
      </li>
      <li>
        <b>19.1.0-canary-fcb4e0f1-20250219</b> - 2025-02-20
      </li>
      <li>
        <b>19.1.0-canary-fc8a898d-20241226</b> - 2024-12-27
      </li>
      <li>
        <b>19.1.0-canary-fbcda19a-20250317</b> - 2025-03-17
      </li>
      <li>
        <b>19.1.0-canary-f9d78089-20250306</b> - 2025-03-07
      </li>
      <li>
        <b>19.1.0-canary-f83903bf-20250212</b> - 2025-02-12
      </li>
      <li>
        <b>19.1.0-canary-f457d0b4-20250313</b> - 2025-03-13
      </li>
      <li>
        <b>19.1.0-canary-f0edf41e-20250115</b> - 2025-01-14
      </li>
      <li>
        <b>19.1.0-canary-ef979d47-20241218</b> - 2024-12-18
      </li>
      <li>
        <b>19.1.0-canary-ef4bc8b4-20250328</b> - 2025-03-28
      </li>
      <li>
        <b>19.1.0-canary-ebc22ef7-20250225</b> - 2025-02-26
      </li>
      <li>
        <b>19.1.0-canary-e670e72f-20250214</b> - 2025-02-14
      </li>
      <li>
        <b>19.1.0-canary-e1e74071-20250321</b> - 2025-03-21
      </li>
      <li>
        <b>19.1.0-canary-e06c72fc-20241215</b> - 2024-12-16
      </li>
      <li>
        <b>19.1.0-canary-e03ac20f-20250305</b> - 2025-03-05
      </li>
      <li>
        <b>19.1.0-canary-de82912e-20241220</b> - 2024-12-20
      </li>
      <li>
        <b>19.1.0-canary-de1eaa26-20250124</b> - 2025-01-24
      </li>
      <li>
        <b>19.1.0-canary-db7dfe05-20250319</b> - 2025-03-19
      </li>
      <li>
        <b>19.1.0-canary-d85cf3e5-20250205</b> - 2025-02-05
      </li>
      <li>
        <b>19.1.0-canary-d55cc79b-20250228</b> - 2025-02-28
      </li>
      <li>
        <b>19.1.0-canary-d46b04a2-20250117</b> - 2025-01-17
      </li>
      <li>
        <b>19.1.0-canary-d4287258-20241217</b> - 2024-12-17
      </li>
      <li>
        <b>19.1.0-canary-d331ba04-20250307</b> - 2025-03-10
      </li>
      <li>
        <b>19.1.0-canary-cd90a4d8-20250210</b> - 2025-02-11
      </li>
      <li>
        <b>19.1.0-canary-cbbe8666-20250213</b> - 2025-02-13
      </li>
      <li>
        <b>19.1.0-canary-cabd8a0e-20250113</b> - 2025-01-13
      </li>
      <li>
        <b>19.1.0-canary-c69a5fc5-20250318</b> - 2025-03-18
      </li>
      <li>
        <b>19.1.0-canary-c492f975-20250128</b> - 2025-01-29
      </li>
      <li>
        <b>19.1.0-canary-c01b8058-20241229</b> - 2024-12-30
      </li>
      <li>
        <b>19.1.0-canary-bb9a24d9-20250130</b> - 2025-01-30
      </li>
      <li>
        <b>19.1.0-canary-b3a95caf-20250113</b> - 2025-01-14
      </li>
      <li>
        <b>19.1.0-canary-b158439a-20250115</b> - 2025-01-15
      </li>
      <li>
        <b>19.1.0-canary-ae9017ce-20250122</b> - 2025-01-23
      </li>
      <li>
        <b>19.1.0-canary-a84862db-20250218</b> - 2025-02-19
      </li>
      <li>
        <b>19.1.0-canary-a4f9bd58-20250319</b> - 2025-03-20
      </li>
      <li>
        <b>19.1.0-canary-a4b2d0d5-20250203</b> - 2025-02-03
      </li>
      <li>
        <b>19.1.0-canary-9ff42a87-20250130</b> - 2025-01-31
      </li>
      <li>
        <b>19.1.0-canary-9eabb373-20250124</b> - 2025-01-27
      </li>
      <li>
        <b>19.1.0-canary-9b62ee71-20250122</b> - 2025-01-22
      </li>
      <li>
        <b>19.1.0-canary-97d79495-20241223</b> - 2024-12-24
      </li>
      <li>
        <b>19.1.0-canary-9463d51e-20241219</b> - 2024-12-19
      </li>
      <li>
        <b>19.1.0-canary-93b58361-20250209</b> - 2025-02-10
      </li>
      <li>
        <b>19.1.0-canary-8a7b487e-20250218</b> - 2025-02-18
      </li>
      <li>
        <b>19.1.0-canary-8759c5c8-20250207</b> - 2025-02-07
      </li>
      <li>
        <b>19.1.0-canary-7eb8234f-20241218</b> - 2024-12-18
      </li>
      <li>
        <b>19.1.0-canary-7b402084-20250107</b> - 2025-01-07
      </li>
      <li>
        <b>19.1.0-canary-74ea0c73-20250109</b> - 2025-01-09
      </li>
      <li>
        <b>19.1.0-canary-740a4f7a-20250325</b> - 2025-03-25
      </li>
      <li>
        <b>19.1.0-canary-7130d0c6-20241212</b> - 2024-12-12
      </li>
      <li>
        <b>19.1.0-canary-6aa8254b-20250312</b> - 2025-03-12
      </li>
      <li>
        <b>19.1.0-canary-694d3e1a-20241231</b> - 2025-01-01
      </li>
      <li>
        <b>19.1.0-canary-6907aa2a-20241220</b> - 2024-12-23
      </li>
      <li>
        <b>19.1.0-canary-662957cc-20250221</b> - 2025-02-21
      </li>
      <li>
        <b>19.1.0-canary-62208bee-20250102</b> - 2025-01-02
      </li>
      <li>
        <b>19.1.0-canary-5b51a2b9-20250116</b> - 2025-01-16
      </li>
      <li>
        <b>19.1.0-canary-540efebc-20250112</b> - 2025-01-12
      </li>
      <li>
        <b>19.1.0-canary-5398b711-20250314</b> - 2025-03-14
      </li>
      <li>
        <b>19.1.0-canary-518d06d2-20241219</b> - 2024-12-19
      </li>
      <li>
        <b>19.1.0-canary-4dff0e62-20241213</b> - 2024-12-13
      </li>
      <li>
        <b>19.1.0-canary-4632e36a-20250216</b> - 2025-02-17
      </li>
      <li>
        <b>19.1.0-canary-443b7ff2-20250303</b> - 2025-03-04
      </li>
      <li>
        <b>19.1.0-canary-4280563b-20250326</b> - 2025-03-27
      </li>
      <li>
        <b>19.1.0-canary-42687267-20250108</b> - 2025-01-08
      </li>
      <li>
        <b>19.1.0-canary-3ce77d55-20250106</b> - 2025-01-06
      </li>
      <li>
        <b>19.1.0-canary-3b009b4c-20250102</b> - 2025-01-03
      </li>
      <li>
        <b>19.1.0-canary-37906d4d-20250127</b> - 2025-01-28
      </li>
      <li>
        <b>19.1.0-canary-32b0cad8-20250213</b> - 2025-02-13
      </li>
      <li>
        <b>19.1.0-canary-313332d1-20250326</b> - 2025-03-26
      </li>
      <li>
        <b>19.1.0-canary-2980f277-20250301</b> - 2025-03-03
      </li>
      <li>
        <b>19.1.0-canary-25677265-20250224</b> - 2025-02-24
      </li>
      <li>
        <b>19.1.0-canary-22e39ea7-20250225</b> - 2025-02-25
      </li>
      <li>
        <b>19.1.0-canary-18eaf51b-20250118</b> - 2025-01-20
      </li>
      <li>
        <b>19.1.0-canary-130095f7-20241212</b> - 2024-12-12
      </li>
      <li>
        <b>19.1.0-canary-0ca3deeb-20250311</b> - 2025-03-11
      </li>
      <li>
        <b>19.1.0-canary-0a82580b-20250203</b> - 2025-02-04
      </li>
      <li>
        <b>19.1.0-canary-056073de-20250109</b> - 2025-01-10
      </li>
      <li>
        <b>19.1.0-canary-029e8bd6-20250306</b> - 2025-03-06
      </li>
      <li>
<b>19.0.0</b> - <a
href="https://github.com/facebook/react/releases/tag/v19.0.0">2024-12-05</a></br><p>Below
is a list of all new features, APIs, deprecations, and breaking changes.
Read <a href="https://react.dev/blog/2024/04/25/react-19"
rel="nofollow">React 19 release post</a> and <a
href="https://react.dev/blog/2024/04/25/react-19-upgrade-guide"
rel="nofollow">React 19 upgrade guide</a> for more information.</p>
<blockquote>
<p>Note: To help make the upgrade to React 19 easier, we’ve published a
react@18.3 release that is identical to 18.2 but adds warnings for
deprecated APIs and other changes that are needed for React 19. We
recommend upgrading to React 18.3.1 first to help identify any issues
before upgrading to React 19.</p>
</blockquote>
<h2>New Features</h2>
<h3>React</h3>
<ul>
<li>Actions: <code>startTransition</code> can now accept async
functions. Functions passed to <code>startTransition</code> are called
“Actions”. A given Transition can include one or more Actions which
update state in the background and update the UI with one commit. In
addition to updating state, Actions can now perform side effects
including async requests, and the Action will wait for the work to
finish before finishing the Transition. This feature allows Transitions
to include side effects like <code>fetch()</code> in the pending state,
and provides support for error handling, and optimistic updates.</li>
<li><code>useActionState</code>: is a new hook to order Actions inside
of a Transition with access to the state of the action, and the pending
state. It accepts a reducer that can call Actions, and the initial state
used for first render. It also accepts an optional string that is used
if the action is passed to a form <code>action</code> prop to support
progressive enhancement in forms.</li>
<li><code>useOptimistic</code>: is a new hook to update state while a
Transition is in progress. It returns the state, and a set function that
can be called inside a transition to “optimistically” update the state
to expected final value immediately while the Transition completes in
the background. When the transition finishes, the state is updated to
the new value.</li>
<li><code>use</code>: is a new API that allows reading resources in
render. In React 19, <code>use</code> accepts a promise or Context. If
provided a promise, <code>use</code> will suspend until a value is
resolved. <code>use</code> can only be used in render but can be called
conditionally.</li>
<li><code>ref</code> as a prop: Refs can now be used as props, removing
the need for <code>forwardRef</code>.</li>
<li><strong>Suspense sibling pre-warming</strong>: When a component
suspends, React will immediately commit the fallback of the nearest
Suspense boundary, without waiting for the entire sibling tree to
render. After the fallback commits, React will schedule another render
for the suspended siblings to “pre-warm” lazy requests.</li>
</ul>
<h3>React DOM Client</h3>
<ul>
<li><code>&lt;form&gt; action</code> prop: Form Actions allow you to
manage forms automatically and integrate with
<code>useFormStatus</code>. When a <code>&lt;form&gt; action</code>
succeeds, React will automatically reset the form for uncontrolled
components. The form can be reset manually with the new
<code>requestFormReset</code> API.</li>
<li><code>&lt;button&gt; and &lt;input&gt; formAction</code> prop:
Actions can be passed to the <code>formAction</code> prop to configure
form submission behavior. This allows using different Actions depending
on the input.</li>
<li><code>useFormStatus</code>: is a new hook that provides the status
of the parent <code>&lt;form&gt; action</code>, as if the form was a
Context provider. The hook returns the values: <code>pending</code>,
<code>data</code>, <code>method</code>, and <code>action</code>.</li>
<li>Support for Document Metadata: We’ve added support for rendering
document metadata tags in components natively. React will automatically
hoist them into the <code>&lt;head&gt;</code> section of the
document.</li>
<li>Support for Stylesheets: React 19 will ensure stylesheets are
inserted into the <code>&lt;head&gt;</code> on the client before
revealing the content of a Suspense boundary that depends on that
stylesheet.</li>
<li>Support for async scripts: Async scripts can be rendered anywhere in
the component tree and React will handle ordering and
deduplication.</li>
<li>Support for preloading resources: React 19 ships with
<code>preinit</code>, <code>preload</code>, <code>prefetchDNS</code>,
and <code>preconnect</code> APIs to optimize initial page loads by
moving discovery of additional resources like fonts out of stylesheet
loading. They can also be used to prefetch resources used by an
anticipated navigation.</li>
</ul>
<h3>React DOM Server</h3>
<ul>
<li>Added <code>prerender</code> and <code>prerenderToNodeStream</code>
APIs for static site generation. They are designed to work with
streaming environments like Node.js Streams and Web Streams. Unlike
<code>renderToString</code>, they wait for data to load for HTML
generation.</li>
</ul>
<h3>React Server Components</h3>
<ul>
<li>RSC features such as directives, server components, and server
functions are now stable. This means libraries that ship with Server
Components can now target React 19 as a peer dependency with a
react-server export condition for use in frameworks that support the
Full-stack React Architecture. The underlying APIs used to implement a
React Server Components bundler or framework do not follow semver and
may break between minors in React 19.x. See <a
href="https://19.react.dev/reference/rsc/server-components"
rel="nofollow">docs</a> for how to support React Server Components.</li>
</ul>
<h2>Deprecations</h2>
<ul>
<li>Deprecated: <code>element.ref</code> access: React 19 supports ref
as a prop, so we’re deprecating <code>element.ref</code> in favor of
<code>element.props.ref</code>. Accessing will result in a warning.</li>
<li><code>react-test-renderer</code>: In React 19, react-test-renderer
logs a deprecation warning and has switched to concurrent rendering for
web usage. We recommend migrating your tests to @
testinglibrary.com/docs/react-testing-library/intro/) or @
testingesting-library.com/docs/react-native-testing-library/intro)</li>
</ul>
<h2>Breaking Changes</h2>
<p>React 19 brings in a number of breaking changes, including the
removals of long-deprecated APIs. We recommend first upgrading to
<code>18.3.1</code>, where we've added additional deprecation warnings.
Check out the <a
href="https://19.react.dev/blog/2024/04/25/react-19-upgrade-guide"
rel="nofollow">upgrade guide</a> for more details and guidance on
codemodding.</p>
<h3>React</h3>
<ul>
<li>New JSX Transform is now required: We introduced <a
href="https://legacy.reactjs.org/blog/2020/09/22/introducing-the-new-jsx-transform.html"
rel="nofollow">a new JSX transform</a> in 2020 to improve bundle size
and use JSX without importing React. In React 19, we’re adding
additional improvements like using ref as a prop and JSX speed
improvements that require the new transform.</li>
<li>Errors in render are not re-thrown: Errors that are not caught by an
Error Boundary are now reported to window.reportError. Errors that are
caught by an Error Boundary are reported to console.error. We’ve
introduced <code>onUncaughtError</code> and <code>onCaughtError</code>
methods to <code>createRoot</code> and <code>hydrateRoot</code> to
customize this error handling.</li>
<li>Removed: <code>propTypes</code>: Using <code>propTypes</code> will
now be silently ignored. If required, we recommend migrating to
TypeScript or another type-checking solution.</li>
<li>Removed: <code>defaultProps</code> for functions: ES6 default
parameters can be used in place. Class components continue to support
<code>defaultProps</code> since there is no ES6 alternative.</li>
<li>Removed: <code>contextTypes</code> and <code>getChildContext</code>:
Legacy Context for class components has been removed in favor of the
<code>contextType</code> API.</li>
<li>Removed: string refs: Any usage of string refs need to be migrated
to ref callbacks.</li>
<li>Removed: Module pattern factories: A rarely used pattern that can be
migrated to regular functions.</li>
<li>Removed: <code>React.createFactory</code>: Now that JSX is broadly
supported, all <code>createFactory</code> usage can be migrated to JSX
components.</li>
<li>Removed: <code>react-test-renderer/shallow</code>: This has been a
re-export of <a
href="https://github.com/enzymejs/react-shallow-renderer">react-shallow-renderer</a>
since React 18. If needed, you can continue to use the third-party
package directly. We recommend using @
testinglibrary.com/docs/react-testing-library/intro/) or @
testingesting-library.com/docs/react-native-testing-library/intro)
instead.</li>
</ul>
<h3>React DOM</h3>
<ul>
<li>Removed: <code>react-dom/test-utils</code>: We’ve moved
<code>act</code> from <code>react-dom/test-utils</code> to react. All
other utilities have been removed.</li>
<li>Removed: <code>ReactDOM</code>.<code>render</code>,
<code>ReactDOM</code>.<code>hydrate</code>: These have been removed in
favor of the concurrent equivalents:
<code>ReactDOM</code>.<code>createRoot</code> and
<code>ReactDOM.hydrateRoot</code>.</li>
<li>Removed: <code>unmountComponentAtNode</code>: Removed in favor of
<code>root.unmount()</code>.</li>
<li>Removed: <code>ReactDOM</code>.<code>findDOMNode</code>: You can
replace <code>ReactDOM</code>.<code>findDOMNode</code> with DOM
Refs.</li>
</ul>
<h2>Notable Changes</h2>
<h3>React</h3>
<ul>
<li><code>&lt;Context&gt;</code> as a provider: You can now render
<code>&lt;Context&gt;</code> as a provider instead of
<code>&lt;Context.Provider&gt;</code>.</li>
<li>Cleanup functions for refs: When the component unmounts, React will
call the cleanup function returned from the ref callback.</li>
<li><code>useDeferredValue</code> initial value argument: When provided,
<code>useDeferredValue</code> will return the initial value for the
initial render of a component, then schedule a re-render in the
background with the <code>deferredValue</code> returned.</li>
<li>Support for Custom Elements: React 19 now passes all tests on <a
href="https://custom-elements-everywhere.com/" rel="nofollow">Custom
Elements Everywhere</a>.</li>
<li>StrictMode changes: <code>useMemo</code> and
<code>useCallback</code> will now reuse the memoized results from the
first render, during the second render. Additionally, StrictMode will
now double-invoke ref callback functions on initial mount.</li>
<li>UMD builds removed: To load React 19 with a script tag, we recommend
using an ESM-based CDN such as <a href="http://esm.sh"
rel="nofollow">esm.sh</a>.</li>
</ul>
<h3>React DOM</h3>
<ul>
<li>Diffs for hydration errors: In the case of a mismatch, React 19 logs
a single error with a diff of the mismatched content.</li>
<li>Compatibility with third-party scripts and extensions: React will
now force a client re-render to fix up any mismatched content caused by
elements inserted by third-party JS.</li>
</ul>
<h2>TypeScript Changes</h2>
<p>The most common changes can be codemodded with <code>npx
types-react-codemod@latest preset-19
./path-to-your-react-ts-files</code>.</p>
<ul>
<li>Removed deprecated TypeScript types:
<ul>
<li><code>ReactChild</code> (replacement: <code>React.ReactElement |
number | string)</code></li>
<li><code>ReactFragment</code> (replacement:
<code>Iterable&lt;React.ReactNode&gt;</code>)</li>
<li><code>ReactNodeArray</code> (replacement:
<code>ReadonlyArray&lt;React.ReactNode&gt;</code>)</li>
<li><code>ReactText</code> (replacement: <code>number |
string</code>)</li>
<li><code>VoidFunctionComponent</code> (replacement:
<code>FunctionComponent</code>)</li>
<li><code>VFC</code> (replacement: <code>FC</code>)</li>
<li>Moved to <code>prop-types</code>: <code>Requireable</code>,
<code>ValidationMap</code>, <code>Validator</code>,
<code>WeakValidationMap</code></li>
<li>Moved to <code>create-react-class</code>:
<code>ClassicComponentClass</code>, <code>ClassicComponent</code>,
<code>ClassicElement</code>, <code>ComponentSpec</code>,
<code>Mixin</code>, <code>ReactChildren</code>, <code>ReactHTML</code>,
<code>ReactSVG</code>, <code>SFCFactory</code></li>
</ul>
</li>
<li>Disallow implicit return in refs: refs can now accept cleanup
functions. When you return something else, we can’t tell if you
intentionally returned something not meant to clean up or returned the
wrong value. Implicit returns of anything but functions will now
error.</li>
<li>Require initial argument to <code>useRef</code>: The initial
argument is now required to match <code>useState</code>,
<code>createContext</code> etc</li>
<li>Refs are mutable by default: Ref objects returned from
<code>useRef()</code> are now always mutable instead of sometimes being
immutable. This feature was too confusing for users and conflicted with
legit cases where refs were managed by React and manually written
to.</li>
<li>Strict <code>ReactElement</code> typing: The props of React elements
now default to <code>unknown</code> instead of <code>any</code> if the
element is typed as <code>ReactElement</code></li>
<li>JSX namespace in TypeScript: The global <code>JSX</code> namespace
is removed to improve interoperability with other libraries using JSX.
Instead, the JSX namespace is available from the React package:
<code>import { JSX } from 'react'</code></li>
<li>Better <code>useReducer</code> typings: Most <code>useReducer</code>
usage should not require explicit type arguments.<br>
For example,
<div class="highlight highlight-source-diff notranslate
position-relative overflow-auto"
data-snippet-clipboard-copy-content="-useReducer&lt;React.Reducer&lt;State,
Action&gt;&gt;(reducer)
+useReducer(reducer) "><pre><span class="pl-md"><span
class="pl-md">-</span>useReducer&lt;React.Reducer&lt;State,
Action&gt;&gt;(reducer) </span>
<span class="pl-mi1"><span class="pl-mi1">+</span>useReducer(reducer)
</span></pre></div>
or
<div class="highlight highlight-source-diff notranslate
position-relative overflow-auto"
data-snippet-clipboard-copy-content="-useReducer&lt;React.Reducer&lt;State,
Action&gt;&gt;(reducer)
+useReducer&lt;State, [Action]&gt;(reducer)"><pre><span
class="pl-md"><span
class="pl-md">-</span>useReducer&lt;React.Reducer&lt;State,
Action&gt;&gt;(reducer) </span>
<span class="pl-mi1"><span class="pl-mi1">+</span>useReducer&lt;State,
[Action]&gt;(reducer)</span></pre></div>
</li>
</ul>
<h2>All Changes</h2>
<h3>React</h3>
<ul>
<li>Add support for async Actions (<a
href="https://github.com/facebook/react/pull/26621"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26621/hovercard">#26621</a>, <a
href="https://github.com/facebook/react/pull/26726"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26726/hovercard">#26726</a>, <a
href="https://github.com/facebook/react/pull/28078"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28078/hovercard">#28078</a>, <a
href="https://github.com/facebook/react/pull/28097"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28097/hovercard">#28097</a>, <a
href="https://github.com/facebook/react/pull/29226"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29226/hovercard">#29226</a>, <a
href="https://github.com/facebook/react/pull/29618"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29618/hovercard">#29618</a>, <a
href="https://github.com/facebook/react/pull/29670"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29670/hovercard">#29670</a>, <a
href="https://github.com/facebook/react/pull/26716"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26716/hovercard">#26716</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a> and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sebmarkbage/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sebmarkbage">@ sebmarkbage</a>)</li>
<li>Add <code>useActionState()</code> hook to update state based on the
result of a Form Action (<a
href="https://github.com/facebook/react/pull/27270"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27270/hovercard">#27270</a>, <a
href="https://github.com/facebook/react/pull/27278"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27278/hovercard">#27278</a>, <a
href="https://github.com/facebook/react/pull/27309"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27309/hovercard">#27309</a>, <a
href="https://github.com/facebook/react/pull/27302"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27302/hovercard">#27302</a>, <a
href="https://github.com/facebook/react/pull/27307"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27307/hovercard">#27307</a>, <a
href="https://github.com/facebook/react/pull/27366"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27366/hovercard">#27366</a>, <a
href="https://github.com/facebook/react/pull/27370"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27370/hovercard">#27370</a>, <a
href="https://github.com/facebook/react/pull/27321"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27321/hovercard">#27321</a>, <a
href="https://github.com/facebook/react/pull/27374"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27374/hovercard">#27374</a>, <a
href="https://github.com/facebook/react/pull/27372"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27372/hovercard">#27372</a>, <a
href="https://github.com/facebook/react/pull/27397"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27397/hovercard">#27397</a>, <a
href="https://github.com/facebook/react/pull/27399"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27399/hovercard">#27399</a>, <a
href="https://github.com/facebook/react/pull/27460"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27460/hovercard">#27460</a>, <a
href="https://github.com/facebook/react/pull/28557"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28557/hovercard">#28557</a>, <a
href="https://github.com/facebook/react/pull/27570"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27570/hovercard">#27570</a>, <a
href="https://github.com/facebook/react/pull/27571"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27571/hovercard">#27571</a>, <a
href="https://github.com/facebook/react/pull/28631"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28631/hovercard">#28631</a>, <a
href="https://github.com/facebook/react/pull/28788"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28788/hovercard">#28788</a>, <a
href="https://github.com/facebook/react/pull/29694"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29694/hovercard">#29694</a>, <a
href="https://github.com/facebook/react/pull/29695"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29695/hovercard">#29695</a>, <a
href="https://github.com/facebook/react/pull/29694"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29694/hovercard">#29694</a>, <a
href="https://github.com/facebook/react/pull/29665"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/29665/hovercard">#29665</a>, <a
href="https://github.com/facebook/react/pull/28232"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28232/hovercard">#28232</a>, <a
href="https://github.com/facebook/react/pull/28319"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28319/hovercard">#28319</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/eps1lon/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/eps1lon">@ eps1lon</a>, and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/rickhanlonii/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/rickhanlonii">@ rickhanlonii</a>)</li>
<li>Add <code>use()</code> API to read resources in render (<a
href="https://github.com/facebook/react/pull/25084"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25084/hovercard">#25084</a>, <a
href="https://github.com/facebook/react/pull/25202"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25202/hovercard">#25202</a>, <a
href="https://github.com/facebook/react/pull/25207"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25207/hovercard">#25207</a>, <a
href="https://github.com/facebook/react/pull/25214"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25214/hovercard">#25214</a>, <a
href="https://github.com/facebook/react/pull/25226"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25226/hovercard">#25226</a>, <a
href="https://github.com/facebook/react/pull/25247"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25247/hovercard">#25247</a>, <a
href="https://github.com/facebook/react/pull/25539"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25539/hovercard">#25539</a>, <a
href="https://github.com/facebook/react/pull/25538"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25538/hovercard">#25538</a>, <a
href="https://github.com/facebook/react/pull/25537"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25537/hovercard">#25537</a>, <a
href="https://github.com/facebook/react/pull/25543"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25543/hovercard">#25543</a>, <a
href="https://github.com/facebook/react/pull/25561"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25561/hovercard">#25561</a>, <a
href="https://github.com/facebook/react/pull/25620"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25620/hovercard">#25620</a>, <a
href="https://github.com/facebook/react/pull/25615"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25615/hovercard">#25615</a>, <a
href="https://github.com/facebook/react/pull/25922"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25922/hovercard">#25922</a>, <a
href="https://github.com/facebook/react/pull/25641"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25641/hovercard">#25641</a>, <a
href="https://github.com/facebook/react/pull/25634"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25634/hovercard">#25634</a>, <a
href="https://github.com/facebook/react/pull/26232"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26232/hovercard">#26232</a>, <a
href="https://github.com/facebook/react/pull/26535"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26535/hovercard">#26536</a>, <a
href="https://github.com/facebook/react/pull/26739"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26739/hovercard">#26739</a>, <a
href="https://github.com/facebook/react/pull/28233"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28233/hovercard">#28233</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/mofeiZ/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/mofeiZ">@ mofeiZ</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sebmarkbage/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sebmarkbage">@ sebmarkbage</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sophiebits/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sophiebits">@ sophiebits</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/eps1lon/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/eps1lon">@ eps1lon</a>, and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/hansottowirtz/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/hansottowirtz">@
hansottowirtz</a>)</li>
<li>Add <code>useOptimistic()</code> hook to display mutated state
optimistically during an async mutation (<a
href="https://github.com/facebook/react/pull/26740"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26740/hovercard">#26740</a>, <a
href="https://github.com/facebook/react/pull/26772"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26772/hovercard">#26772</a>, <a
href="https://github.com/facebook/react/pull/27277"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27277/hovercard">#27277</a>, <a
href="https://github.com/facebook/react/pull/27453"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27453/hovercard">#27453</a>, <a
href="https://github.com/facebook/react/pull/27454"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27454/hovercard">#27454</a>, <a
href="https://github.com/facebook/react/pull/27936"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27936/hovercard">#27936</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Added an <code>initialValue</code> argument to
<code>useDeferredValue()</code> hook (<a
href="https://github.com/facebook/react/pull/27500"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27500/hovercard">#27500</a>, <a
href="https://github.com/facebook/react/pull/27509"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27509/hovercard">#27509</a>, <a
href="https://github.com/facebook/react/pull/27512"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27512/hovercard">#27512</a>, <a
href="https://github.com/facebook/react/pull/27888"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27888/hovercard">#27888</a>, <a
href="https://github.com/facebook/react/pull/27550"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27550/hovercard">#27550</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Support refs as props, warn on <code>element.ref</code> access (<a
href="https://github.com/facebook/react/pull/28348"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28348/hovercard">#28348</a>, <a
href="https://github.com/facebook/react/pull/28464"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28464/hovercard">#28464</a>, <a
href="https://github.com/facebook/react/pull/28731"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28731/hovercard">#28731</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Support Custom Elements (<a
href="https://github.com/facebook/react/pull/22184"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/22184/hovercard">#22184</a>, <a
href="https://github.com/facebook/react/pull/26524"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26524/hovercard">#26524</a>, <a
href="https://github.com/facebook/react/pull/26523"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26523/hovercard">#26523</a>, <a
href="https://github.com/facebook/react/pull/27511"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27511/hovercard">#27511</a>, <a
href="https://github.com/facebook/react/pull/24541"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/24541/hovercard">#24541</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/josepharhar/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/josepharhar">@ josepharhar</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sebmarkbage/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sebmarkbage">@ sebmarkbage</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/gnoff/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/gnoff">@ gnoff</a> and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/eps1lon/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/eps1lon">@ eps1lon</a>)</li>
<li>Add ref cleanup function (<a
href="https://github.com/facebook/react/pull/25686"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25686/hovercard">#25686</a>, <a
href="https://github.com/facebook/react/pull/28883"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28883/hovercard">#28883</a>, <a
href="https://github.com/facebook/react/pull/28910"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28910/hovercard">#28910</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sammy-SC/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sammy-SC">@ sammy-SC</a>), <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/jackpope/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/jackpope">@ jackpope</a>, and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/kassens/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/kassens">@ kassens</a>)</li>
<li>Sibling pre-rendering replaced by sibling pre-warming (<a
href="https://github.com/facebook/react/pull/26380"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26380/hovercard">#26380</a>, <a
href="https://github.com/facebook/react/pull/26549"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26549/hovercard">#26549</a>, <a
href="https://github.com/facebook/react/pull/30761"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30761/hovercard">#30761</a>, <a
href="https://github.com/facebook/react/pull/30800"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30800/hovercard">#30800</a>, <a
href="https://github.com/facebook/react/pull/30762"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30762/hovercard">#30762</a>, <a
href="https://github.com/facebook/react/pull/30879"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30879/hovercard">#30879</a>, <a
href="https://github.com/facebook/react/pull/30934"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30934/hovercard">#30934</a>, <a
href="https://github.com/facebook/react/pull/30952"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/30952/hovercard">#30952</a>, <a
href="https://github.com/facebook/react/pull/31056"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31056/hovercard">#31056</a>, <a
href="https://github.com/facebook/react/pull/31452"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/31452/hovercard">#31452</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sammy-SC/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sammy-SC">@ sammy-SC</a>), <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/gnoff/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/gnoff">@ gnoff</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/jackpope/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/jackpope">@ jackpope</a>, <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/rickhanlonii/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/rickhanlonii">@ rickhanlonii</a>)</li>
<li>Don’t rethrow errors at the root (<a
href="https://github.com/facebook/react/pull/28627"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28627/hovercard">#28627</a>, <a
href="https://github.com/facebook/react/pull/28641"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28641/hovercard">#28641</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sebmarkbage/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sebmarkbage">@ sebmarkbage</a>)</li>
<li>Batch sync discrete, continuous, and default lanes (<a
href="https://github.com/facebook/react/pull/25700"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25700/hovercard">#25700</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/tyao1/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/tyao1">@ tyao1</a>)</li>
<li>Switch <code>&lt;Context&gt;</code> to mean
<code>&lt;Context.Provider&gt;</code> (<a
href="https://github.com/facebook/react/pull/28226"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28226/hovercard">#28226</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/gaearon/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/gaearon">@ gaearon</a>)</li>
<li>Changes to <em>StrictMode</em>
<ul>
<li>Handle <code>info</code>, <code>group</code>, and
<code>groupCollapsed</code> in <em>StrictMode</em> logging (<a
href="https://github.com/facebook/react/pull/25172"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25172/hovercard">#25172</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/timneutkens/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/timneutkens">@ timneutkens</a>)</li>
<li>Refs are now attached/detached/attached in <em>StrictMode</em> (<a
href="https://github.com/facebook/react/pull/25049"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25049/hovercard">#25049</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sammy-SC/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sammy-SC">@ sammy-SC</a>)</li>
<li>Fix <code>useSyncExternalStore()</code> hydration in
<em>StrictMode</em> (<a
href="https://github.com/facebook/react/pull/26791"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26791/hovercard">#26791</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sophiebits/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sophiebits">@ sophiebits</a>)</li>
<li>Always trigger <code>componentWillUnmount()</code> in
<em>StrictMode</em> (<a
href="https://github.com/facebook/react/pull/26842"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26842/hovercard">#26842</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/tyao1/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/tyao1">@ tyao1</a>)</li>
<li>Restore double invoking <code>useState()</code> and
<code>useReducer()</code> initializer functions in <em>StrictMode</em>
(<a href="https://github.com/facebook/react/pull/28248"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/28248/hovercard">#28248</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/eps1lon/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/eps1lon">@ eps1lon</a>)</li>
<li>Reuse memoized result from first pass (<a
href="https://github.com/facebook/react/pull/25583"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25583/hovercard">#25583</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Fix <code>useId()</code> in <em>StrictMode</em> (<a
href="https://github.com/facebook/react/pull/25713"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25713/hovercard">#25713</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/gnoff/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/gnoff">@ gnoff</a>)</li>
<li>Add component name to <em>StrictMode</em> error messages (<a
href="https://github.com/facebook/react/pull/25718"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25718/hovercard">#25718</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sammy-SC/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sammy-SC">@ sammy-SC</a>)</li>
</ul>
</li>
<li>Add support for rendering BigInt (<a
href="https://github.com/facebook/react/pull/24580"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/24580/hovercard">#24580</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/eps1lon/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/eps1lon">@ eps1lon</a>)</li>
<li><code>act()</code> no longer checks <code>shouldYield</code> which
can be inaccurate in test environments (<a
href="https://github.com/facebook/react/pull/26317"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26317/hovercard">#26317</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Warn when keys are spread with props (<a
href="https://github.com/facebook/react/pull/25697"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25697/hovercard">#25697</a>, <a
href="https://github.com/facebook/react/pull/26080"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26080/hovercard">#26080</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/sebmarkbage/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/sebmarkbage">@ sebmarkbage</a> and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/kassens/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/kassens">@ kassens</a>)</li>
<li>Generate sourcemaps for production build artifacts (<a
href="https://github.com/facebook/react/pull/26446"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26446/hovercard">#26446</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/markerikson/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/markerikson">@ markerikson</a>)</li>
<li>Improve stack diffing algorithm (<a
href="https://github.com/facebook/react/pull/27132"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/27132/hovercard">#27132</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/KarimP/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/KarimP">@ KarimP</a>)</li>
<li>Suspense throttling lowered from 500ms to 300ms (<a
href="https://github.com/facebook/react/pull/26803"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26803/hovercard">#26803</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Lazily propagate context changes (<a
href="https://github.com/facebook/react/pull/20890"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/20890/hovercard">#20890</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a> and <a
class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/gnoff/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/gnoff">@ gnoff</a>)</li>
<li>Immediately rerender pinged fiber (<a
href="https://github.com/facebook/react/pull/25074"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/25074/hovercard">#25074</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Move update scheduling to microtask (<a
href="https://github.com/facebook/react/pull/26512"
data-hovercard-type="pull_request"
data-hovercard-url="/facebook/react/pull/26512/hovercard">#26512</a> by
<a class="user-mention notranslate" data-hovercard-type="user"
data-hovercard-url="/users/acdlite/hovercard"
data-octo-click="hovercard-link-click"
data-octo-dimensions="link_type:self"
href="https://github.com/acdlite">@ acdlite</a>)</li>
<li>Consistently apply throttled retries (<a
href="https://github.com/facebook/…
# for free to join this conversation on GitHub. Already have an account? # to comment
Labels
CLA Signed React Core Team Opened by a member of the React Core Team React 19
Projects
None yet
Development

Successfully merging this pull request may close these issues.

Bug: useFormState formAction becomes null in strict mode
4 participants