From 7a36dfedc70ffb49be2e4e23b40e01d34cef267e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Markb=C3=A5ge?= <sebastian@calyptus.eu>
Date: Sat, 16 Aug 2025 12:16:58 -0400
Subject: [PATCH] [Fizz] Delay retrying hydration until after an animation
 frame (#34220)

The theory here is that when we reveal a boundary coming from the server
we want to paint that before hydrating it. Hydration gets scheduled in a
macrotask with the scheduler but it's in theory possible that it runs
before the paint. If that's the case, then the JS that runs before
yielding during hydration might slightly delay the paint and we might
miss a window to skip the previous paint.
---
 .../ReactDOMFizzInstructionSetInlineCodeStrings.js              | 2 +-
 .../fizz-instruction-set/ReactDOMFizzInstructionSetShared.js    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetInlineCodeStrings.js b/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetInlineCodeStrings.js
index 0cfff921d0a..8c4a0a8e9a0 100644
--- a/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetInlineCodeStrings.js
+++ b/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetInlineCodeStrings.js
@@ -6,7 +6,7 @@ export const markShellTime =
 export const clientRenderBoundary =
   '$RX=function(b,c,d,e,f){var a=document.getElementById(b);a&&(b=a.previousSibling,b.data="$!",a=a.dataset,c&&(a.dgst=c),d&&(a.msg=d),e&&(a.stck=e),f&&(a.cstck=f),b._reactRetry&&b._reactRetry())};';
 export const completeBoundary =
-  '$RB=[];$RV=function(b){$RT=performance.now();for(var a=0;a<b.length;a+=2){var c=b[a],e=b[a+1];null!==e.parentNode&&e.parentNode.removeChild(e);var f=c.parentNode;if(f){var g=c.previousSibling,h=0;do{if(c&&8===c.nodeType){var d=c.data;if("/$"===d||"/&"===d)if(0===h)break;else h--;else"$"!==d&&"$?"!==d&&"$~"!==d&&"$!"!==d&&"&"!==d||h++}d=c.nextSibling;f.removeChild(c);c=d}while(c);for(;e.firstChild;)f.insertBefore(e.firstChild,c);g.data="$";g._reactRetry&&g._reactRetry()}}b.length=0};\n$RC=function(b,a){if(a=document.getElementById(a))(b=document.getElementById(b))?(b.previousSibling.data="$~",$RB.push(b,a),2===$RB.length&&(b="number"!==typeof $RT?0:$RT,a=performance.now(),setTimeout($RV.bind(null,$RB),2300>a&&2E3<a?2300-a:b+300-a))):a.parentNode.removeChild(a)};';
+  '$RB=[];$RV=function(b){$RT=performance.now();for(var a=0;a<b.length;a+=2){var c=b[a],e=b[a+1];null!==e.parentNode&&e.parentNode.removeChild(e);var f=c.parentNode;if(f){var g=c.previousSibling,h=0;do{if(c&&8===c.nodeType){var d=c.data;if("/$"===d||"/&"===d)if(0===h)break;else h--;else"$"!==d&&"$?"!==d&&"$~"!==d&&"$!"!==d&&"&"!==d||h++}d=c.nextSibling;f.removeChild(c);c=d}while(c);for(;e.firstChild;)f.insertBefore(e.firstChild,c);g.data="$";g._reactRetry&&requestAnimationFrame(g._reactRetry)}}b.length=0};\n$RC=function(b,a){if(a=document.getElementById(a))(b=document.getElementById(b))?(b.previousSibling.data="$~",$RB.push(b,a),2===$RB.length&&(b="number"!==typeof $RT?0:$RT,a=performance.now(),setTimeout($RV.bind(null,$RB),2300>a&&2E3<a?2300-a:b+300-a))):a.parentNode.removeChild(a)};';
 export const completeBoundaryUpgradeToViewTransitions =
   '$RV=function(A,g){function k(a,b){var e=a.getAttribute(b);e&&(b=a.style,l.push(a,b.viewTransitionName,b.viewTransitionClass),"auto"!==e&&(b.viewTransitionClass=e),(a=a.getAttribute("vt-name"))||(a="_T_"+K++ +"_"),b.viewTransitionName=a,B=!0)}var B=!1,K=0,l=[];try{var f=document.__reactViewTransition;if(f){f.finished.finally($RV.bind(null,g));return}var m=new Map;for(f=1;f<g.length;f+=2)for(var h=g[f].querySelectorAll("[vt-share]"),d=0;d<h.length;d++){var c=h[d];m.set(c.getAttribute("vt-name"),c)}var u=[];for(h=0;h<g.length;h+=2){var C=g[h],x=C.parentNode;if(x){var v=x.getBoundingClientRect();if(v.left||v.top||v.width||v.height){c=C;for(f=0;c;){if(8===c.nodeType){var r=c.data;if("/$"===r)if(0===f)break;else f--;else"$"!==r&&"$?"!==r&&"$~"!==r&&"$!"!==r||f++}else if(1===c.nodeType){d=c;var D=d.getAttribute("vt-name"),y=m.get(D);k(d,y?"vt-share":"vt-exit");y&&(k(y,"vt-share"),m.set(D,null));var E=d.querySelectorAll("[vt-share]");for(d=0;d<E.length;d++){var F=E[d],G=F.getAttribute("vt-name"),\nH=m.get(G);H&&(k(F,"vt-share"),k(H,"vt-share"),m.set(G,null))}}c=c.nextSibling}for(var I=g[h+1],t=I.firstElementChild;t;)null!==m.get(t.getAttribute("vt-name"))&&k(t,"vt-enter"),t=t.nextElementSibling;c=x;do for(var n=c.firstElementChild;n;){var J=n.getAttribute("vt-update");J&&"none"!==J&&!l.includes(n)&&k(n,"vt-update");n=n.nextElementSibling}while((c=c.parentNode)&&1===c.nodeType&&"none"!==c.getAttribute("vt-update"));u.push.apply(u,I.querySelectorAll(\'img[src]:not([loading="lazy"])\'))}}}if(B){var z=\ndocument.__reactViewTransition=document.startViewTransition({update:function(){A(g);for(var a=[document.documentElement.clientHeight,document.fonts.ready],b={},e=0;e<u.length;b={g:b.g},e++)if(b.g=u[e],!b.g.complete){var p=b.g.getBoundingClientRect();0<p.bottom&&0<p.right&&p.top<window.innerHeight&&p.left<window.innerWidth&&(p=new Promise(function(w){return function(q){w.g.addEventListener("load",q);w.g.addEventListener("error",q)}}(b)),a.push(p))}return Promise.race([Promise.all(a),new Promise(function(w){var q=\nperformance.now();setTimeout(w,2300>q&&2E3<q?2300-q:500)})])},types:[]});z.ready.finally(function(){for(var a=l.length-3;0<=a;a-=3){var b=l[a],e=b.style;e.viewTransitionName=l[a+1];e.viewTransitionClass=l[a+1];""===b.getAttribute("style")&&b.removeAttribute("style")}});z.finished.finally(function(){document.__reactViewTransition===z&&(document.__reactViewTransition=null)});$RB=[];return}}catch(a){}A(g)}.bind(null,$RV);';
 export const completeBoundaryWithStyles =
diff --git a/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetShared.js b/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetShared.js
index 89321679914..aa8d4cf94c3 100644
--- a/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetShared.js
+++ b/packages/react-dom-bindings/src/server/fizz-instruction-set/ReactDOMFizzInstructionSetShared.js
@@ -94,7 +94,7 @@ export function revealCompletedBoundaries(batch) {
 
     suspenseNode.data = SUSPENSE_START_DATA;
     if (suspenseNode['_reactRetry']) {
-      suspenseNode['_reactRetry']();
+      requestAnimationFrame(suspenseNode['_reactRetry']);
     }
   }
   batch.length = 0;