diff --git a/apps/web/src/components/chat/MessagesTimeline.tsx b/apps/web/src/components/chat/MessagesTimeline.tsx
index 4b15b8090b00e3ba961c50e1d00fdee29a6507bc..dafa8161bd2037d0c22d786440ca5ced6795840e 100644
--- a/apps/web/src/components/chat/MessagesTimeline.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.tsx
@@ -234,7 +234,7 @@ export const MessagesTimeline = memo(function MessagesTimeline({
   // from TimelineRowCtx, which propagates through LegendList's memo.
   const renderItem = useCallback(
     ({ item }: { item: MessagesTimelineRow }) => (
-      <div className="mx-auto w-full min-w-0 max-w-3xl overflow-x-hidden" data-timeline-root="true">
+      <div className="mx-auto w-full min-w-0 max-w-3xl overflow-x-clip" data-timeline-root="true">
         <TimelineRowContent row={item} />
       </div>
     ),
@@ -663,7 +663,7 @@ function AssistantChangedFilesSectionInner({
 
   return (
     <div className="mt-2 rounded-lg border border-border/80 bg-card/45 p-2.5">
-      <div className="mb-1.5 flex items-center justify-between gap-2">
+      <div className="sticky top-2 z-10 mb-1.5 flex items-center justify-between gap-2 bg-background before:absolute before:inset-x-0 before:-top-2 before:h-2 before:bg-background before:content-['']">
         <p className="text-[10px] uppercase tracking-[0.12em] text-muted-foreground/65">
           <span>Changed files ({changedFileCountLabel})</span>
           {hasNonZeroStat(summaryStat) && (