diff --git a/desktop/src/components/chat/MessageList.test.tsx b/desktop/src/components/chat/MessageList.test.tsx
index 195d7e3a..f7f8f6ad 100644
--- a/desktop/src/components/chat/MessageList.test.tsx
+++ b/desktop/src/components/chat/MessageList.test.tsx
@@ -120,14 +120,22 @@ describe('MessageList nested tool calls', () => {
     })
   })
 
-  it('window-renders long transcripts while keeping the latest messages visible', () => {
+  it('keeps full long transcripts mounted so variable-height messages cannot leave spacer gaps', () => {
     useChatStore.setState({
       sessions: {
         [ACTIVE_TAB]: makeSessionState({
           messages: Array.from({ length: 220 }, (_, index) => ({
             id: `assistant-${index}`,
             type: 'assistant_text',
-            content: `assistant transcript line ${index}`,
+            content: index % 25 === 0
+              ? [
+                  `assistant transcript line ${index}`,
+                  '',
+                  '```ts',
+                  'const value = "this intentionally makes the row much taller"',
+                  '```',
+                ].join('\n')
+              : `assistant transcript line ${index}`,
             timestamp: index,
           })),
         }),
@@ -136,9 +144,10 @@ describe('MessageList nested tool calls', () => {
 
     const { container } = render(<MessageList />)
 
-    expect(screen.queryByText('assistant transcript line 0')).toBeNull()
+    expect(screen.getByText('assistant transcript line 0')).toBeTruthy()
     expect(screen.getByText('assistant transcript line 219')).toBeTruthy()
-    expect(container.querySelectorAll('[data-message-shell="assistant"]').length).toBeLessThan(140)
+    expect(container.querySelectorAll('[data-message-shell="assistant"]').length).toBe(220)
+    expect(container.querySelector('[data-virtual-message-item]')).toBeNull()
   })
 
   it('renders goal events as visible status cards', () => {
@@ -221,7 +230,7 @@ describe('MessageList nested tool calls', () => {
     expect(container.querySelectorAll('[data-message-shell="assistant"]').length).toBe(220)
   })
 
-  it('window-renders long histories that include tool-call groups', async () => {
+  it('keeps long histories with tool-call groups mounted while scrolling history', async () => {
     useChatStore.setState({
       sessions: {
         [ACTIVE_TAB]: makeSessionState({
@@ -259,7 +268,7 @@ describe('MessageList nested tool calls', () => {
     Object.defineProperty(scrollArea, 'scrollHeight', { configurable: true, value: 222 * 112 })
     await waitForProgrammaticScrollReset()
 
-    expect(screen.queryByText('Read')).toBeNull()
+    expect(screen.getByText('Read')).toBeTruthy()
     expect(screen.getByText('assistant transcript line 219')).toBeTruthy()
 
     scrollArea.scrollTop = 0
@@ -269,7 +278,7 @@ describe('MessageList nested tool calls', () => {
 
     expect(screen.getByText('Read')).toBeTruthy()
     expect(screen.getByText('assistant transcript line 219')).toBeTruthy()
-    expect(container.querySelectorAll('[data-virtual-message-item]').length).toBe(221)
+    expect(container.querySelector('[data-virtual-message-item]')).toBeNull()
   })
 
   it('renders sub-agent tool calls inline beneath the parent agent tool call', () => {
diff --git a/desktop/src/components/chat/MessageList.tsx b/desktop/src/components/chat/MessageList.tsx
index abd74ca9..edfefaec 100644
--- a/desktop/src/components/chat/MessageList.tsx
+++ b/desktop/src/components/chat/MessageList.tsx
@@ -537,8 +537,6 @@ type MessageListProps = {
 
 const AUTO_SCROLL_BOTTOM_THRESHOLD_PX = 48
 const MAX_SCROLL_SNAPSHOTS = 100
-const VIRTUALIZE_MIN_ITEMS = 160
-const VIRTUAL_INITIAL_ITEMS = 96
 const CHAT_SCROLL_AREA_CLASS = [
   'chat-scroll-area',
   '[scrollbar-width:auto]',
@@ -590,10 +588,6 @@ function getBottomScrollTop(element: HTMLElement) {
   return Math.max(0, element.scrollHeight - element.clientHeight)
 }
 
-function getRenderItemKey(item: RenderItem) {
-  return item.kind === 'tool_group' ? item.id : item.message.id
-}
-
 export function MessageList({ sessionId, compact = false }: MessageListProps = {}) {
   const activeTabId = useTabStore((s) => s.activeTabId)
   const resolvedSessionId = sessionId ?? activeTabId
@@ -623,7 +617,6 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
   const isProgrammaticScrollingRef = useRef(false)
   const lastSessionIdRef = useRef<string | null | undefined>(resolvedSessionId)
   const lastTailMessageIdBySessionRef = useRef(new Map<string, string | null>())
-  const updateVirtualWindowRef = useRef<((element: HTMLElement) => void) | null>(null)
   const t = useTranslation()
   const [turnChangeCards, setTurnChangeCards] = useState<TurnChangeCardModel[]>([])
   const [turnChangeLoadError, setTurnChangeLoadError] = useState<string | null>(null)
@@ -693,7 +686,6 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
     if (resolvedSessionId) {
       rememberSessionScroll(resolvedSessionId, container)
     }
-    updateVirtualWindowRef.current?.(container)
   }, [resolvedSessionId])
 
   useLayoutEffect(() => {
@@ -759,58 +751,6 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
     () => buildRenderModel(messages),
     [messages],
   )
-  const shouldVirtualize = renderItems.length > VIRTUALIZE_MIN_ITEMS
-  const [virtualRange, setVirtualRange] = useState(() => ({ start: 0, end: 0 }))
-
-  const updateVirtualWindow = useCallback((container: HTMLElement | null) => {
-    if (!shouldVirtualize) {
-      setVirtualRange((current) =>
-        current.start === 0 && current.end === renderItems.length
-          ? current
-          : { start: 0, end: renderItems.length },
-      )
-      return
-    }
-
-    if (!container || shouldAutoScrollRef.current) {
-      const start = Math.max(0, renderItems.length - VIRTUAL_INITIAL_ITEMS)
-      setVirtualRange((current) =>
-        current.start === start && current.end === renderItems.length
-          ? current
-          : { start, end: renderItems.length },
-      )
-      return
-    }
-
-    setVirtualRange((current) =>
-      current.start === 0 && current.end === renderItems.length
-        ? current
-        : { start: 0, end: renderItems.length },
-    )
-  }, [renderItems.length, shouldVirtualize])
-
-  useEffect(() => {
-    updateVirtualWindowRef.current = updateVirtualWindow
-    return () => {
-      if (updateVirtualWindowRef.current === updateVirtualWindow) {
-        updateVirtualWindowRef.current = null
-      }
-    }
-  }, [updateVirtualWindow])
-
-  useLayoutEffect(() => {
-    updateVirtualWindow(scrollContainerRef.current)
-  }, [renderItems.length, resolvedSessionId, updateVirtualWindow])
-
-  const visibleRenderItems = shouldVirtualize
-    ? renderItems.slice(virtualRange.start, virtualRange.end)
-    : renderItems
-  const topVirtualSpacerHeight = shouldVirtualize
-    ? Math.max(0, virtualRange.start * 96)
-    : 0
-  const bottomVirtualSpacerHeight = shouldVirtualize
-    ? Math.max(0, renderItems.length - virtualRange.end) * 96
-    : 0
   const completedTurnTargets = useMemo(() => getCompletedTurnTargets(messages), [messages])
   const latestCompletedTurnId =
     completedTurnTargets.length > 0
@@ -961,25 +901,13 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
         <div
           ref={scrollContentRef}
           className={compact ? 'mx-auto max-w-full' : 'mx-auto max-w-[860px]'}
-          role={shouldVirtualize ? 'list' : undefined}
         >
-          {topVirtualSpacerHeight > 0 && (
-            <div aria-hidden="true" style={{ height: topVirtualSpacerHeight }} />
-          )}
-
-          {visibleRenderItems.map((item, visibleIndex) => {
-            const index = shouldVirtualize ? virtualRange.start + visibleIndex : visibleIndex
-            const itemKey = getRenderItemKey(item)
+          {renderItems.map((item, index) => {
+            const itemKey = item.kind === 'tool_group' ? item.id : item.message.id
             const cardsForItem = turnCardsByRenderIndex.get(index) ?? []
 
             return (
-              <div
-                key={itemKey}
-                data-virtual-message-item={shouldVirtualize ? itemKey : undefined}
-                role={shouldVirtualize ? 'listitem' : undefined}
-                aria-posinset={shouldVirtualize ? index + 1 : undefined}
-                aria-setsize={shouldVirtualize ? renderItems.length : undefined}
-              >
+              <div key={itemKey}>
                 {item.kind === 'tool_group' ? (
                   <ToolCallGroup
                     toolCalls={item.toolCalls}
@@ -1027,10 +955,6 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
             )
           })}
 
-          {bottomVirtualSpacerHeight > 0 && (
-            <div aria-hidden="true" style={{ height: bottomVirtualSpacerHeight }} />
-          )}
-
           {streamingText.trim() && (
             <AssistantMessage content={streamingText} isStreaming={chatState === 'streaming'} />
           )}