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Fix ViewTransition crash in Mobile Safari - #35337

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gaearon merged 2 commits into
mainfrom
maybe-fix-vt
Dec 9, 2025
Merged

Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom
maybe-fix-vt

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@gaearon

@gaearongaearon commented Dec 9, 2025

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Speculative fix to #35336 written by Claude.

I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.

I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.

@gaearongaearon mentioned this pull request Dec 9, 2025
Closed
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Comparing: 55480b4...95d7331

Critical size changes

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

Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against 95d7331

sebmarkbage
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I think this is probably ok.

@sebmarkbage

sebmarkbage commented Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.

@gaearon

gaearon commented Dec 9, 2025

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Yea not sure, I guess let's try it and see if I can hit it again at some other codepath

@gaearongaearon changed the title [Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon merged commit 61331f3 into mainDec 9, 2025
239 checks passed
@gaearon
gaearon deleted the maybe-fix-vt branch December 9, 2025 18:35
github-actionsBot pushed a commit that referenced this pull request Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)
This was referenced Dec 10, 2025
Closed
Closed
@eps1loneps1lon mentioned this pull request Dec 11, 2025
Merged
github-actionsBot pushed a commit to code/lib-react that referenced this pull request Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage

sebmarkbage commented Jan 12, 2026

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One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
Merged
Merged
sebmarkbage added a commit that referenced this pull request Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit that referenced this pull request Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot pushed a commit that referenced this pull request Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte mentioned this pull request Jun 5, 2026
Closed
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@gaearon@react-sizebot@sebmarkbage
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observer.observe(document.body, { childList: true, subtree: true });
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} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
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try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

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Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

@github-actionsgithub-actionsBot
added
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@react-sizebot
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edited

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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
sebmarkbage
sebmarkbage
approved these changes
Dec 9, 2025
View reviewed changes
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I think this is probably ok.
@sebmarkbage
sebmarkbage
commented
Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
gaearon
commented
Dec 9, 2025

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CollaboratorAuthor
Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

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Contributor
One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@gaearon@react-sizebot@sebmarkbage

, 'i');
if (__m === '*' || __re.test(location.href)) {
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var style = document.createElement('style');
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Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

Copy link


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Collaborator
Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

@github-actionsgithub-actionsBot
added
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Opened by a member of the React Core Team
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@react-sizebot
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Dec 9, 2025•

edited

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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
sebmarkbage
sebmarkbage
approved these changes
Dec 9, 2025
View reviewed changes
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I think this is probably ok.
@sebmarkbage
sebmarkbage
commented
Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
gaearon
commented
Dec 9, 2025

Copy link


Copy Markdown

CollaboratorAuthor
Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

Copy link


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Contributor
One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@gaearon@react-sizebot@sebmarkbage

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if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
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var ref = document.referrer;
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Array.from(node.childNodes).forEach(highlight);
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m.addedNodes.forEach(function(node) {
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observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

Copy link


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Collaborator
Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
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I think this is probably ok.
@sebmarkbage
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Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
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Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

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One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@gaearon@react-sizebot@sebmarkbage

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

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Collaborator
Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

@github-actionsgithub-actionsBot
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@react-sizebot
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edited

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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
sebmarkbage
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approved these changes
Dec 9, 2025
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I think this is probably ok.
@sebmarkbage
sebmarkbage
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Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
gaearon
commented
Dec 9, 2025

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CollaboratorAuthor
Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

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One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@gaearon@react-sizebot@sebmarkbage

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

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Collaborator
Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

@github-actionsgithub-actionsBot
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@react-sizebot
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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
sebmarkbage
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approved these changes
Dec 9, 2025
View reviewed changes
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I think this is probably ok.
@sebmarkbage
sebmarkbage
commented
Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
gaearon
commented
Dec 9, 2025

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CollaboratorAuthor
Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

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Contributor
One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@gaearon@react-sizebot@sebmarkbage

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

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Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

@github-actionsgithub-actionsBot
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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
sebmarkbage
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I think this is probably ok.
@sebmarkbage
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Dec 9, 2025

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Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
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Dec 9, 2025

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Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

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One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@gaearon@react-sizebot@sebmarkbage

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
Fix ViewTransition crash in Mobile Safari by gaearon · Pull Request #35337 · react/react · GitHub
Skip to content
Fix ViewTransition crash in Mobile Safari - #35337
Merged
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Dec 9, 2025
Merged
Fix ViewTransition crash in Mobile Safari#35337
gaearon merged 2 commits into
mainfrom 
maybe-fix-vt
Conversation
@gaearon
@gaearongaearon
commented
Dec 9, 2025

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Speculative fix to #35336 written by Claude.
I have verified that applying a similar patch locally to the repro from #35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix is correct or sufficient.
@gaearongaearon
mentioned this pull request
Dec 9, 2025

Closed

@github-actionsgithub-actionsBot
added
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Dec 9, 2025
@react-sizebot
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Dec 9, 2025•

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Comparing: 55480b4...95d7331
Critical size changes
Includes critical production bundles, as well as any change greater than 2%:
Name+/-BaseCurrent+/- gzipBase gzipCurrent gzip
oss-stable/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=608.36 kB608.16 kB=107.68 kB107.67 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.84 kB6.84 kB=1.88 kB1.88 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=667.47 kB667.39 kB=117.57 kB117.55 kB
facebook-www/ReactDOM-prod.classic.js=693.67 kB693.47 kB=122.07 kB122.05 kB
facebook-www/ReactDOM-prod.modern.js=684.10 kB683.89 kB=120.45 kB120.43 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 95d7331
sebmarkbage
sebmarkbage
approved these changes
Dec 9, 2025
View reviewed changes
@sebmarkbagesebmarkbage
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I think this is probably ok.
@sebmarkbage
sebmarkbage
commented
Dec 9, 2025

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Contributor
Not sure if it fixes it in all cases though if the staleness also happens to apply to any of these.
@gaearon
gaearon
commented
Dec 9, 2025

Copy link


Copy Markdown

CollaboratorAuthor
Yea not sure, I guess let's try it and see if I can hit it again at some other codepath
@gaearongaearon
changed the title
[Speculative fix] Fix ViewTransition crash in Mobile SafariFix ViewTransition crash in Mobile SafariDec 9, 2025
@gaearon
gaearon
merged commit 61331f3
into
mainDec 9, 2025

239 checks passed

@gaearon
gaearon
deleted the

maybe-fix-vt

branch
December 9, 2025 18:35
github-actionsBot
pushed a commit
that referenced
this pull request
Dec 9, 2025
@gaearon
Fix ViewTransition crash in Mobile Safari (#35337)
ceea2c9
Speculative fix to #35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](61331f3)

This was referenced Dec 10, 2025
 Closed

 Closed

@eps1loneps1lon
mentioned this pull request
Dec 11, 2025
 Merged

github-actionsBot
pushed a commit
to code/lib-react
that referenced
this pull request
Dec 14, 2025
@pull
Fix ViewTransition crash in Mobile Safari (react#35337)
5cbc7be
Speculative fix to react#35336
written by Claude.
I have verified that applying a similar patch locally to the repro from
react#35336 does fix the crash.
I'm not familiar enough with the underlying APIs to tell whether the fix
is correct or sufficient.
DiffTrain build for [61331f3](react@61331f3)
@sebmarkbage
sebmarkbage
commented
Jan 12, 2026

Copy link


Copy Markdown

Contributor
One unfortunate consequence of this is that if you spawn custom Animations using the refs passed to onExit, onEnter, onUpdate, onShare callbacks. E.g. to do JS powered animations. If you do that then they're not automatically cancelled by this mechanism since they're started later. There's no signal coming from React for when to cancel the animation.

This was referenced Jan 19, 2026
 Merged

 Merged

sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Properly clean up gesture Animations (#35559)
a49952b
Follow up to #35337.
During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.
An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.
sebmarkbage added a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
c55ffb5
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
github-actionsBot
pushed a commit
that referenced
this pull request
Jan 20, 2026
@sebmarkbage
Add Clean Up Callbacks to View Transition and Gesture Transition Even…
fbbbcef
…ts (#35564)
Stacked on #35556 and #35559.
Given that we don't automatically clean up all view transition
animations since #35337 and browsers are buggy, it's important that you
clean up any `Animation` started manually from the events. However,
there was no clean up function for when the View Transition is forced to
stop. This also makes it harder to clean up custom timers etc too.
This lets you return a clean up function from all the events on
`<ViewTransition>`.
DiffTrain build for [c55ffb5](c55ffb5)
@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@sebmarkbagesebmarkbagesebmarkbage approved these changes
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3 participants

@gaearon@react-sizebot@sebmarkbage