From 8356aa4d2143f734e7c3c7a375c258b736acf929 Mon Sep 17 00:00:00 2001
From: npub1t2tgm7d8f995uqvmnm8h88sg3wnpp9a5xysjf6dg3tjmgt3ltulqdp8ehr
 <5a968df9a7494b4e019b9ecf739e088ba61097b4312124e9a88ae5b42e3f5f3e@sprout-oss.stage.blox.sqprod.co>
Date: Sat, 27 Jun 2026 20:53:35 -0400
Subject: [PATCH] Fix virtualized bottom target after history prepend

Co-authored-by: npub1t2tgm7d8f995uqvmnm8h88sg3wnpp9a5xysjf6dg3tjmgt3ltulqdp8ehr <5a968df9a7494b4e019b9ecf739e088ba61097b4312124e9a88ae5b42e3f5f3e@sprout-oss.stage.blox.sqprod.co>
Signed-off-by: npub1t2tgm7d8f995uqvmnm8h88sg3wnpp9a5xysjf6dg3tjmgt3ltulqdp8ehr <5a968df9a7494b4e019b9ecf739e088ba61097b4312124e9a88ae5b42e3f5f3e@sprout-oss.stage.blox.sqprod.co>
---
 desktop/src/features/messages/ui/useLoadOlderOnScroll.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/desktop/src/features/messages/ui/useLoadOlderOnScroll.ts b/desktop/src/features/messages/ui/useLoadOlderOnScroll.ts
index ca33d88d54..c272013b3d 100644
--- a/desktop/src/features/messages/ui/useLoadOlderOnScroll.ts
+++ b/desktop/src/features/messages/ui/useLoadOlderOnScroll.ts
@@ -38,6 +38,7 @@ type UseLoadOlderOnScrollOptions = {
   virtualizer?: {
     getVirtualizer: () => ListVirtualizer | null;
     indexByMessageId: Map<string, number>;
+    /** Current rendered item count (timeline rows + day/unread dividers). */
     itemCount: number;
     /** Live (non-deferred) message count for growth detection during load-older. */
     liveMessageCount?: number;
@@ -248,7 +249,7 @@ export function useLoadOlderOnScroll({
                 const target = resolveTarget({
                   instance: grew ? instance : null,
                   abandonedToBottom,
-                  lastIndex: (after?.liveMessageCount ?? previousCount) - 1,
+                  lastIndex: (after?.itemCount ?? virt.itemCount) - 1,
                   newIndex,
                   anchorTop,
                 });