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[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005

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[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.

This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.

This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.

However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.

@github-actionsgithub-actionsBot added the React Core Team Opened by a member of the React Core Team label Oct 29, 2025
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Comparing: 0fa3250...515b922

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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against 515b922

@sebmarkbage
sebmarkbage merged commit 4f93170 into react:mainOct 29, 2025
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@nextjs-botnextjs-bot mentioned this pull request Oct 29, 2025
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@eps1loneps1lon mentioned this pull request Nov 17, 2025
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@jere-cojere-co mentioned this pull request Nov 28, 2025
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@rubennorterubennorte mentioned this pull request Jun 5, 2026
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@sebmarkbage@react-sizebot@unstubbable
, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
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[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
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react:mainfrom 
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Oct 29, 2025
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[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
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react:mainfrom 
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Oct 29, 2025

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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
@github-actionsgithub-actionsBot
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
sebmarkbage
merged commit 4f93170
into
react:mainOct 29, 2025

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Nov 17, 2025
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
Skip to content
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
Merged
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Oct 29, 2025
Merged
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
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@sebmarkbage
@sebmarkbagesebmarkbage
commented
Oct 29, 2025

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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
@github-actionsgithub-actionsBot
added
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label
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
sebmarkbage
merged commit 4f93170
into
react:mainOct 29, 2025

246 checks passed

@nextjs-botnextjs-bot
mentioned this pull request
Oct 29, 2025
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@eps1loneps1lon
mentioned this pull request
Nov 17, 2025
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@jere-cojere-co
mentioned this pull request
Nov 28, 2025
 Closed

@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@sebmarkbage@react-sizebot@unstubbable

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
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('^' + ".*" + '
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
Skip to content
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
Merged
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Oct 29, 2025
Merged
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
sebmarkbage merged 2 commits into
react:mainfrom 
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@sebmarkbagesebmarkbage
commented
Oct 29, 2025

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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
@github-actionsgithub-actionsBot
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
sebmarkbage
merged commit 4f93170
into
react:mainOct 29, 2025

246 checks passed

@nextjs-botnextjs-bot
mentioned this pull request
Oct 29, 2025
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@eps1loneps1lon
mentioned this pull request
Nov 17, 2025
 Merged

@jere-cojere-co
mentioned this pull request
Nov 28, 2025
 Closed

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mentioned this pull request
Jun 5, 2026
 Closed

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, '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" + '
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
Skip to content
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
Merged
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Oct 29, 2025
Merged
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
sebmarkbage merged 2 commits into
react:mainfrom 
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@sebmarkbagesebmarkbage
commented
Oct 29, 2025

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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
@github-actionsgithub-actionsBot
added
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label
Oct 29, 2025
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
sebmarkbage
merged commit 4f93170
into
react:mainOct 29, 2025

246 checks passed

@nextjs-botnextjs-bot
mentioned this pull request
Oct 29, 2025
 Merged

@eps1loneps1lon
mentioned this pull request
Nov 17, 2025
 Merged

@jere-cojere-co
mentioned this pull request
Nov 28, 2025
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mentioned this pull request
Jun 5, 2026
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, '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('^' + ".*" + '
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
Skip to content
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
Merged
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Oct 29, 2025
Merged
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
sebmarkbage merged 2 commits into
react:mainfrom 
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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
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merged commit 4f93170
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, '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('^' + ".*" + '
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
Skip to content
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
Merged
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Oct 29, 2025
Merged
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Conversation
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Oct 29, 2025

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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
@github-actionsgithub-actionsBot
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
sebmarkbage
merged commit 4f93170
into
react:mainOct 29, 2025

246 checks passed

@nextjs-botnextjs-bot
mentioned this pull request
Oct 29, 2025
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@eps1loneps1lon
mentioned this pull request
Nov 17, 2025
 Merged

@jere-cojere-co
mentioned this pull request
Nov 28, 2025
 Closed

@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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, '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); }
})();
})();
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths by sebmarkbage · Pull Request #35005 · react/react · GitHub
Skip to content
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths - #35005
Merged
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Oct 29, 2025
Merged
[Flight] Cache the value if we visit the same I/O or Promise multiple times along different paths#35005
sebmarkbage merged 2 commits into
react:mainfrom 
sebmarkbage:cachevisited
Conversation
@sebmarkbage
@sebmarkbagesebmarkbage
commented
Oct 29, 2025

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We avoid visiting the same async node twice but if we see it again we returned "null" indicating that there's no I/O there.
This means that if you have two different Promises both resolving from the same I/O node then we only show one of them. However, in general we treat that as two different I/O entries to allow for things like batching to still show up separately.
This fixes that by caching the return value for multiple visits. So if we found I/O (but no user space await) in one path and then we visit that path through a different Promise chain, then we'll still emit it twice.
However, if we visit the same exact Promise that we emitted an await on then we skip it. Because there's no need to emit two awaits on the same thing. It only matters when the path ends up informing whether it has I/O or not.
@github-actionsgithub-actionsBot
added
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@react-sizebot
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Comparing: 0fa3250...515b922
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=6.68 kB6.68 kB=1.83 kB1.83 kB
oss-stable/react-dom/cjs/react-dom-client.production.js=605.41 kB605.41 kB=107.21 kB107.22 kB
oss-experimental/react-dom/cjs/react-dom.production.js=6.69 kB6.69 kB=1.83 kB1.83 kB
oss-experimental/react-dom/cjs/react-dom-client.production.js=664.38 kB664.38 kB=117.09 kB117.09 kB
facebook-www/ReactDOM-prod.classic.js=688.25 kB688.25 kB=121.13 kB121.13 kB
facebook-www/ReactDOM-prod.modern.js=678.67 kB678.67 kB=119.49 kB119.49 kB
Significant size changes
Includes any change greater than 0.2%:
(No significant changes)

Generated by 🚫 dangerJS against 515b922
@sebmarkbage
sebmarkbage
merged commit 4f93170
into
react:mainOct 29, 2025

246 checks passed

@nextjs-botnextjs-bot
mentioned this pull request
Oct 29, 2025
 Merged

@eps1loneps1lon
mentioned this pull request
Nov 17, 2025
 Merged

@jere-cojere-co
mentioned this pull request
Nov 28, 2025
 Closed

@rubennorterubennorte
mentioned this pull request
Jun 5, 2026
 Closed

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@unstubbableunstubbableunstubbable approved these changes
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@sebmarkbage@react-sizebot@unstubbable