diff --git a/desktop/src/components/chat/MessageList.test.tsx b/desktop/src/components/chat/MessageList.test.tsx
index 5755fce4..c417159e 100644
--- a/desktop/src/components/chat/MessageList.test.tsx
+++ b/desktop/src/components/chat/MessageList.test.tsx
@@ -932,6 +932,77 @@ describe('MessageList nested tool calls', () => {
     expect(scrollIntoView).toHaveBeenCalled()
   })
 
+  it('keeps mobile H5 streaming output pinned after the transcript height grows', async () => {
+    const scrollIntoView = vi.fn()
+    Object.defineProperty(HTMLElement.prototype, 'scrollIntoView', {
+      configurable: true,
+      value: scrollIntoView,
+    })
+
+    useChatStore.setState({
+      sessions: {
+        [ACTIVE_TAB]: makeSessionState({
+          chatState: 'streaming',
+          messages: [
+            {
+              id: 'user-1',
+              type: 'user_text',
+              content: '移动端长回复',
+              timestamp: 1,
+            },
+          ],
+          streamingText: 'streaming',
+        }),
+      },
+    })
+
+    const { container } = render(<MessageList />)
+    const scroller = container.querySelector('.overflow-y-auto') as HTMLDivElement
+    let scrollTop = 552
+    let scrollHeight = 1000
+    Object.defineProperty(scroller, 'scrollHeight', {
+      configurable: true,
+      get: () => scrollHeight,
+    })
+    Object.defineProperty(scroller, 'clientHeight', { configurable: true, value: 400 })
+    Object.defineProperty(scroller, 'scrollTop', {
+      configurable: true,
+      get: () => scrollTop,
+      set: (value) => {
+        scrollTop = value
+      },
+    })
+
+    await waitForProgrammaticScrollReset()
+    fireEvent.scroll(scroller)
+    expect(screen.queryByRole('button', { name: 'Latest' })).toBeNull()
+
+    scrollIntoView.mockClear()
+    scrollHeight = 1400
+    act(() => {
+      useChatStore.setState((state) => ({
+        sessions: {
+          ...state.sessions,
+          [ACTIVE_TAB]: {
+            ...state.sessions[ACTIVE_TAB]!,
+            streamingText: 'streaming next token after height change',
+          },
+        },
+      }))
+    })
+
+    await waitFor(() => {
+      expect(screen.getByText('streaming next token after height change')).toBeTruthy()
+    })
+    expect(scrollIntoView).toHaveBeenCalledWith({ behavior: 'smooth', block: 'end' })
+    expect(scrollTop).toBe(1000)
+
+    await waitForProgrammaticScrollReset()
+    fireEvent.scroll(scroller)
+
+    expect(screen.queryByRole('button', { name: 'Latest' })).toBeNull()
+  })
+
   it('restores a session scroll position when switching back to a tab', async () => {
     const scrollIntoView = vi.fn()
     Object.defineProperty(HTMLElement.prototype, 'scrollIntoView', {
@@ -1120,6 +1191,81 @@ describe('MessageList nested tool calls', () => {
     expect(scrollIntoView).toHaveBeenCalledWith({ behavior: 'smooth', block: 'end' })
   })
 
+  it('jumps to the latest message when the user sends a new prompt from history', async () => {
+    const scrollIntoView = vi.fn()
+    Object.defineProperty(HTMLElement.prototype, 'scrollIntoView', {
+      configurable: true,
+      value: scrollIntoView,
+    })
+
+    useChatStore.setState({
+      sessions: {
+        [ACTIVE_TAB]: makeSessionState({
+          messages: [
+            {
+              id: 'user-1',
+              type: 'user_text',
+              content: '历史消息',
+              timestamp: 1,
+            },
+            {
+              id: 'assistant-1',
+              type: 'assistant_text',
+              content: '历史回复',
+              timestamp: 2,
+            },
+          ],
+        }),
+      },
+    })
+
+    const { container } = render(<MessageList />)
+    const scroller = container.querySelector('.overflow-y-auto') as HTMLDivElement
+    let scrollTop = 120
+    Object.defineProperty(scroller, 'scrollHeight', { configurable: true, value: 1000 })
+    Object.defineProperty(scroller, 'clientHeight', { configurable: true, value: 400 })
+    Object.defineProperty(scroller, 'scrollTop', {
+      configurable: true,
+      get: () => scrollTop,
+      set: (value) => {
+        scrollTop = value
+      },
+    })
+
+    scrollIntoView.mockClear()
+    await waitForProgrammaticScrollReset()
+    fireEvent.scroll(scroller)
+    expect(screen.getByRole('button', { name: 'Latest' })).toBeTruthy()
+
+    act(() => {
+      useChatStore.setState((state) => ({
+        sessions: {
+          ...state.sessions,
+          [ACTIVE_TAB]: {
+            ...state.sessions[ACTIVE_TAB]!,
+            chatState: 'thinking',
+            messages: [
+              ...state.sessions[ACTIVE_TAB]!.messages,
+              {
+                id: 'user-2',
+                type: 'user_text',
+                content: '新的问题',
+                timestamp: 3,
+              },
+            ],
+          },
+        },
+      }))
+    })
+
+    await waitFor(() => {
+      expect(screen.getByText('新的问题')).toBeTruthy()
+    })
+    expect(scrollIntoView).toHaveBeenCalledWith({ behavior: 'smooth', block: 'end' })
+    expect(scrollTop).toBe(600)
+    expect(screen.queryByRole('button', { name: 'Latest' })).toBeNull()
+  })
+
   it('keeps user actions anchored to the right bubble and assistant actions to the left bubble', () => {
     useChatStore.setState({
       sessions: {
diff --git a/desktop/src/components/chat/MessageList.tsx b/desktop/src/components/chat/MessageList.tsx
index ad66286e..2e886c43 100644
--- a/desktop/src/components/chat/MessageList.tsx
+++ b/desktop/src/components/chat/MessageList.tsx
@@ -511,7 +511,11 @@ function rememberSessionScroll(sessionId: string, element: HTMLElement) {
 }
 
 function clampScrollTop(element: HTMLElement, scrollTop: number) {
-  return Math.max(0, Math.min(scrollTop, element.scrollHeight - element.clientHeight))
+  return Math.max(0, Math.min(scrollTop, getBottomScrollTop(element)))
+}
+
+function getBottomScrollTop(element: HTMLElement) {
+  return Math.max(0, element.scrollHeight - element.clientHeight)
 }
 
 function getRenderItemKey(item: RenderItem) {
@@ -541,6 +545,7 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
   const shouldAutoScrollRef = useRef(true)
   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[]>([])
@@ -554,17 +559,39 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
   const scrollToBottom = useCallback((behavior: ScrollBehavior) => {
     shouldAutoScrollRef.current = true
     isProgrammaticScrollingRef.current = true
-    bottomRef.current?.scrollIntoView?.({ behavior, block: 'end' })
     const container = scrollContainerRef.current
+    const targetScrollTop = container ? getBottomScrollTop(container) : null
+    if (container) {
+      container.scrollTop = targetScrollTop ?? 0
+    }
+    bottomRef.current?.scrollIntoView?.({ behavior, block: 'end' })
     if (container && resolvedSessionId) {
       sessionScrollSnapshots.set(resolvedSessionId, {
-        scrollTop: Math.max(0, container.scrollHeight - container.clientHeight),
+        scrollTop: getBottomScrollTop(container),
         wasAtBottom: true,
       })
     }
     setShowJumpToLatest(false)
     // Reset flag after the scroll event(s) from scrollIntoView have fired
     requestAnimationFrame(() => {
+      const latestContainer = scrollContainerRef.current
+      if (
+        shouldAutoScrollRef.current &&
+        latestContainer &&
+        (
+          targetScrollTop === null ||
+          latestContainer.scrollTop === targetScrollTop ||
+          isNearScrollBottom(latestContainer)
+        )
+      ) {
+        latestContainer.scrollTop = getBottomScrollTop(latestContainer)
+        if (resolvedSessionId) {
+          sessionScrollSnapshots.set(resolvedSessionId, {
+            scrollTop: getBottomScrollTop(latestContainer),
+            wasAtBottom: true,
+          })
+        }
+      }
       isProgrammaticScrollingRef.current = false
     })
   }, [resolvedSessionId])
@@ -601,6 +628,22 @@ export function MessageList({ sessionId, compact = false }: MessageListProps = {
     }
   }, [resolvedSessionId, scrollToBottom])
 
+  const tailMessage = messages[messages.length - 1] ?? null
+  const tailMessageId = tailMessage?.id ?? null
+  const tailMessageType = tailMessage?.type ?? null
+
+  useEffect(() => {
+    if (!resolvedSessionId) return
+
+    const previousTailMessageId = lastTailMessageIdBySessionRef.current.get(resolvedSessionId)
+    lastTailMessageIdBySessionRef.current.set(resolvedSessionId, tailMessageId)
+    if (previousTailMessageId === undefined || previousTailMessageId === tailMessageId) return
+
+    if (tailMessageType === 'user_text' && chatState !== 'idle') {
+      scrollToBottom('smooth')
+    }
+  }, [chatState, resolvedSessionId, scrollToBottom, tailMessageId, tailMessageType])
+
   useEffect(() => {
     if (!shouldAutoScrollRef.current) {
       setShowJumpToLatest(true)