diff --git a/src/components/AiChat.vue b/src/components/AiChat.vue
index cbb4f88..c387ba7 100644
--- a/src/components/AiChat.vue
+++ b/src/components/AiChat.vue
@@ -242,7 +242,7 @@ async function confirmClearChat() {
  * 新建对话(UX-08 §3.4):生成中点新建 → 弹 ConfirmDialog「当前正在生成,确定中断并新建?」,
  * 确认走原软复位流程(B-260615-10 store.newConversation,中断 + 新建);取消不动(保持生成)。
  * 非生成中直接走原新建流程(零行为变化)。仅「当前视图正在生成」才弹确认 ——
- * 切走后台生成时(streaming && generatingConvId !== activeConversationId)不算中断当前视图。
+ * 切走后台生成时(streaming && !isGenerating(activeConversationId))不算中断当前视图。
  */
 async function confirmNewConversation() {
   if (isViewingGenerating.value) {
@@ -277,8 +277,10 @@ const convSidebarRef = ref<InstanceType<typeof ConversationSidebar> | null>(null
 // (顶部工具栏 + provider/model 选择逻辑,零行为变更,store 单例共享 modelOverride)。
 
 // 当前视图是否正在生成(切走后台生成时光标不显示)
+// F-09: 多会话并发 — 用 isGenerating(activeConversationId) 替代单值比对,
+// 当前会话在生成 Set 中即算"视图正在生成"(其他会话后台生成不影响本视图判定)
 const isViewingGenerating = computed(() =>
-  store.state.streaming && store.state.generatingConvId === store.state.activeConversationId
+  store.state.streaming && store.isGenerating(store.state.activeConversationId)
 )
 
 /** UX-09:进入编辑态 — 置 editingMsgId(透传 ChatInput prop)+ 委托 ChatInput.startEditFocus 回填/聚焦。 */
@@ -806,6 +808,22 @@ body.ai-sidebar-resizing * {
   font-size: 9px;
   color: var(--df-text-dim);
 }
+/* F-09: 多会话并发生成指示器(会话项标题行内脉冲点,多会话可同时显示) */
+.ai-conv-gen-dot {
+  display: inline-block;
+  width: 6px;
+  height: 6px;
+  border-radius: 50%;
+  background: var(--df-primary, #4f8cff);
+  margin-left: 4px;
+  vertical-align: middle;
+  flex-shrink: 0;
+  animation: ai-conv-gen-pulse 1.4s ease-in-out infinite;
+}
+@keyframes ai-conv-gen-pulse {
+  0%, 100% { opacity: 0.35; transform: scale(0.85); }
+  50% { opacity: 1; transform: scale(1.15); }
+}
 .ai-conv-item-actions {
   display: none;
   align-items: center;
diff --git a/src/components/ai/ConversationSidebar.vue b/src/components/ai/ConversationSidebar.vue
index 15ef76c..e7bb83c 100644
--- a/src/components/ai/ConversationSidebar.vue
+++ b/src/components/ai/ConversationSidebar.vue
@@ -45,7 +45,10 @@
             @click="onSelectSearchResult(conv.id)"
           >
             <div class="ai-conv-item-main">
-              <span class="ai-conv-item-title" :title="conv.title || ''">{{ conv.title || t('aiChat.newConversation') }}</span>
+              <span class="ai-conv-item-title" :title="conv.title || ''">
+                {{ conv.title || t('aiChat.newConversation') }}
+                <span v-if="store.isGenerating(conv.id)" class="ai-conv-gen-dot" :title="t('aiChat.generating')"></span>
+              </span>
               <span class="ai-conv-item-time">{{ formatTime(conv.updated_at) }}</span>
             </div>
             <div class="ai-conv-item-actions">
@@ -125,6 +128,8 @@
                     class="ai-conv-item-title-badge"
                     width="9" height="9" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"
                   ><polyline points="20 6 9 17 4 12"/></svg>
+                  <!-- F-09: 多会话并发生成指示器(后台/当前会话生成中均显脉冲点,多会话可同时显示) -->
+                  <span v-if="store.isGenerating(conv.id)" class="ai-conv-gen-dot" :title="t('aiChat.generating')"></span>
                 </span>
                 <span class="ai-conv-item-time">{{ formatTime(conv.updated_at) }}</span>
               </div>
@@ -167,7 +172,10 @@
               @click="store.switchConversation(conv.id)"
             >
               <div class="ai-conv-item-main">
-                <span class="ai-conv-item-title" :title="conv.title || ''">{{ conv.title || t('aiChat.newConversation') }}</span>
+                <span class="ai-conv-item-title" :title="conv.title || ''">
+                  {{ conv.title || t('aiChat.newConversation') }}
+                  <span v-if="store.isGenerating(conv.id)" class="ai-conv-gen-dot" :title="t('aiChat.generating')"></span>
+                </span>
                 <span class="ai-conv-item-time">{{ formatTime(conv.updated_at) }}</span>
               </div>
               <div class="ai-conv-item-actions">
diff --git a/src/components/ai/DirAuthDialog.vue b/src/components/ai/DirAuthDialog.vue
index 61c5a7d..3db8ab8 100644
--- a/src/components/ai/DirAuthDialog.vue
+++ b/src/components/ai/DirAuthDialog.vue
@@ -46,8 +46,9 @@ const store = useAiStore()
 const { t } = useI18n()
 
 // 当前视图是否正在生成(切走后台生成时光标不显示,与 MaxRoundsCard 一致守卫)
+// F-09: 多会话并发 — isGenerating(active) 替代单值比对
 const isViewingGenerating = computed(() =>
-  store.state.streaming && store.state.generatingConvId === store.state.activeConversationId,
+  store.state.streaming && store.isGenerating(store.state.activeConversationId),
 )
 
 // pendingDirAuth(AiDirAuthRequired 事件置)+ 当前视图正在生成(防切走后误显)双重守卫。
diff --git a/src/components/ai/MaxRoundsCard.vue b/src/components/ai/MaxRoundsCard.vue
index 06db5bd..69e3e7c 100644
--- a/src/components/ai/MaxRoundsCard.vue
+++ b/src/components/ai/MaxRoundsCard.vue
@@ -38,8 +38,9 @@ const store = useAiStore()
 const { t } = useI18n()
 
 // 当前视图是否正在生成(切走后台生成时光标不显示)
+// F-09: 多会话并发 — isGenerating(active) 替代单值比对
 const isViewingGenerating = computed(() =>
-  store.state.streaming && store.state.generatingConvId === store.state.activeConversationId,
+  store.state.streaming && store.isGenerating(store.state.activeConversationId),
 )
 
 // pendingMaxRounds(达 max 事件置)+ 当前视图正在生成(防切走后误显)双重守卫。
diff --git a/src/components/ai/MessageList.vue b/src/components/ai/MessageList.vue
index d9e970f..d07fb7b 100644
--- a/src/components/ai/MessageList.vue
+++ b/src/components/ai/MessageList.vue
@@ -192,8 +192,9 @@ const messagesContainer = ref<HTMLDivElement>()
 const toolCardListRef = ref<InstanceType<typeof ToolCardList>>()
 
 // 当前视图是否正在生成(切走后台生成时光标不显示)
+// F-09: 多会话并发 — isGenerating(active) 替代单值比对
 const isViewingGenerating = computed(() =>
-  store.state.streaming && store.state.generatingConvId === store.state.activeConversationId
+  store.state.streaming && store.isGenerating(store.state.activeConversationId)
 )
 
 function isLastAi(msg: AiMessage): boolean {
@@ -347,10 +348,10 @@ watch(() => store.state.streaming, (s) => {
   if (rafId !== null) { cancelAnimationFrame(rafId); rafId = null }
   if (s) {
     // UX-260616-03: 新一轮生成开始 → 收起上一轮已完成的旧工具卡,聚焦当前生成内容。
-    // 仅当前视图正在生成时触发(generatingConvId 对齐 activeConversationId),
+    // 仅当前视图正在生成时触发(isGenerating(activeConversationId)),
     // 切走后台生成/恢复会话(streaming 初值已 true 的 onMounted 路径)不误触。
     // buildActiveToolIds/collapseAllToolLists 是 function 声明,提升可用。
-    if (store.state.generatingConvId === store.state.activeConversationId) {
+    if (store.isGenerating(store.state.activeConversationId)) {
       collapseAllToolLists(buildActiveToolIds(store.state.messages))
     }
   } else {
diff --git a/src/composables/ai/useAiConversations.ts b/src/composables/ai/useAiConversations.ts
index 8ace172..3a6fce9 100644
--- a/src/composables/ai/useAiConversations.ts
+++ b/src/composables/ai/useAiConversations.ts
@@ -72,10 +72,10 @@ async function newConversation() {
   state.pendingApprovals = []
   state.streaming = false
   // F-260616-09(A 路线):补漏清字段维持单例软隔离,解「新建会话上下文残留」。
-  // queue 清空防旧会话排队消息被带进新会话 drain;generatingConvId 清空防后台事件
+  // queue 清空防旧会话排队消息被带进新会话 drain;generatingConvs 清空防后台事件
   // 错误路由;agentRound 复位 0;searchQuery 清空防新会话侧栏被旧搜索过滤。
   state.queue = []
-  state.generatingConvId = null
+  state.generatingConvs.clear()
   state.agentRound = 0
   state.searchQuery = ''
   await loadConversations()
diff --git a/src/composables/ai/useAiEvents.ts b/src/composables/ai/useAiEvents.ts
index 8f49982..8c47c06 100644
--- a/src/composables/ai/useAiEvents.ts
+++ b/src/composables/ai/useAiEvents.ts
@@ -359,7 +359,7 @@ function handleLifecycleEvent(event: AiChatEvent): boolean {
       flushCurrentText()
       state.currentText = ''
       state.streaming = false
-      state.generatingConvId = null
+      state.generatingConvs.delete(event.conversation_id || '')
       state.agentRound = 0 // AE-2025-07: agentic 结束,复位轮次(隐藏进度条)
       pendingMaxRounds.value = false // F-260616-03: 收尾(停止/续跑后新一轮达 max 才会再 set),清操作卡
       pendingDirAuth.value = null // F-260619-03 Phase B: 收尾清路径授权弹窗(防残留)
@@ -389,7 +389,12 @@ function handleLifecycleEvent(event: AiChatEvent): boolean {
           state.convTokenTotal = { prompt: event.prompt_tokens, completion: event.completion_tokens, total: event.total_tokens }
         }
       }
-      // 清理分离窗口生成态快照
+      // 清理分离窗口生成态快照(F-09:per-conv key,清本会话快照;兼容旧单 key)
+      const doneConv = event.conversation_id || ''
+      if (doneConv) {
+        localStorage.removeItem(`df-ai-gen-${doneConv}`)
+        localStorage.removeItem(`df-ai-text-${doneConv}`)
+      }
       localStorage.removeItem('df-ai-gen')
       localStorage.removeItem('df-ai-text')
       void loadConversations()
@@ -407,7 +412,7 @@ function handleLifecycleEvent(event: AiChatEvent): boolean {
       // 保留"回答到一半"的部分回复(否则清 currentText 后部分内容消失)。
       flushCurrentText()
       state.streaming = false
-      state.generatingConvId = null
+      state.generatingConvs.delete(event.conversation_id || '')
       state.currentText = ''
       state.agentRound = 0 // AE-2025-07: agentic 异常中断,复位轮次
       state.queue = [] // B-32:错误收尾清队列,防生成中入队的消息被静默丢失(drainQueue 仅 AiCompleted 触发)
@@ -416,6 +421,12 @@ function handleLifecycleEvent(event: AiChatEvent): boolean {
       state.pendingApprovals = []
       pendingMaxRounds.value = false // F-260616-03: 异常中断,清操作卡
       pendingDirAuth.value = null // F-260619-03 Phase B: 异常中断清路径授权弹窗
+      // F-09: 清理分离窗口生成态快照(per-conv key,清本会话快照;兼容旧单 key)
+      const errConv = event.conversation_id || ''
+      if (errConv) {
+        localStorage.removeItem(`df-ai-gen-${errConv}`)
+        localStorage.removeItem(`df-ai-text-${errConv}`)
+      }
       localStorage.removeItem('df-ai-gen')
       localStorage.removeItem('df-ai-text')
       // UX-03: 错误消息携带 error_type(供错误气泡差异化显隐「去设置」按钮)。
@@ -450,14 +461,15 @@ export function handleEvent(event: AiChatEvent) {
   const isCurrent = !convId || convId === state.activeConversationId
   if (!isCurrent) {
     if (event.type === 'AiCompleted' || event.type === 'AiError') {
-      state.generatingConvId = null
+      // F-09: 多会话并发 — 仅从 Set 移除该 conv(其他会话可能仍在生成),不再置 null 全局清空
+      state.generatingConvs.delete(convId || '')
       void loadConversations()
     }
     return
   }
   // 标记正在生成的对话(完成/错误事件除外)
   if (convId && event.type !== 'AiCompleted' && event.type !== 'AiError') {
-    state.generatingConvId = convId
+    state.generatingConvs.add(convId)
   }
   // 流式看门狗:活跃事件(delta/工具/新轮/审批结果)重置;审批等待/完成/错误在 case 内 clear
   if (!NO_RESET_WATCHDOG.has(event.type)) {
diff --git a/src/composables/ai/useAiStream.ts b/src/composables/ai/useAiStream.ts
index ade03b5..b9e109c 100644
--- a/src/composables/ai/useAiStream.ts
+++ b/src/composables/ai/useAiStream.ts
@@ -25,7 +25,9 @@ let _streamWatchdog: ReturnType<typeof setTimeout> | null = null
 /** 看门狗超时回调:收尾 streaming 态并补错误消息 */
 export function onStreamTimeout() {
   state.streaming = false
-  state.generatingConvId = null
+  // F-09: 多会话并发 — 超时收尾清空全部生成态(整流超时是兜底场景,无法确定具体 conv,
+  // 保守全清避免幽灵;正常路径由各 conv 的 AiCompleted/AiError 精确 remove)
+  state.generatingConvs.clear()
   state.currentText = ''
   state.queue = [] // B-32:超时收尾同步清队列,防生成中入队的消息静默丢失
   clearStreamWatchdog()
diff --git a/src/composables/ai/useAiWindow.ts b/src/composables/ai/useAiWindow.ts
index 7e6a7c7..79673fc 100644
--- a/src/composables/ai/useAiWindow.ts
+++ b/src/composables/ai/useAiWindow.ts
@@ -17,30 +17,55 @@ import { persistUiState } from './useAiPanel'
 let _unlistenMove: (() => void) | null = null
 let _unlistenResize: (() => void) | null = null
 
-/** 分离 AI 面板到独立窗口(若已存在则聚焦);快照当前生成态供分离窗口接管 */
-async function detachPanel() {
+/**
+ * F-09 阶段4:多会话独立窗口的 per-conv key/label 生成器。
+ *
+ * 旧实现用单 label 'ai-detached' + 单 key df-ai-gen/df-ai-text,多会话并发下冲突
+ * (会话 A 的窗口快照被会话 B 覆盖,getByLabel 只能存一个窗口)。现按 convId 命名空间
+ * 隔离:每个会话独立窗口 + 独立 localStorage 快照,互不串扰。
+ * 单会话场景:convId 固定,key/label 退化为单值,行为等价。
+ */
+const DETACHED_LABEL_PREFIX = 'ai-detached-'
+const GEN_KEY_PREFIX = 'df-ai-gen-'
+const TEXT_KEY_PREFIX = 'df-ai-text-'
+
+function detachedLabel(convId: string): string {
+  return DETACHED_LABEL_PREFIX + convId
+}
+function genKey(convId: string): string {
+  return GEN_KEY_PREFIX + convId
+}
+function textKey(convId: string): string {
+  return TEXT_KEY_PREFIX + convId
+}
+
+/** 分离 AI 面板到独立窗口(若该会话窗口已存在则聚焦);快照当前生成态供分离窗口接管 */
+async function detachPanel(convId?: string) {
   const { WebviewWindow } = await import('@tauri-apps/api/webviewWindow')
-  const existing = await WebviewWindow.getByLabel('ai-detached')
+  const targetConv = convId || state.activeConversationId || ''
+  const label = targetConv ? detachedLabel(targetConv) : 'ai-detached'
+  const existing = await WebviewWindow.getByLabel(label)
   if (existing) {
     await existing.setFocus()
     return
   }
   // 快照当前生成态,供分离窗口接管(保持正在进行的对话)
-  if (state.streaming && state.generatingConvId) {
-    localStorage.setItem('df-ai-gen', state.generatingConvId)
-    localStorage.setItem('df-ai-text', state.currentText)
+  // F-09:用 per-conv key 写入(多会话各自快照互不覆盖)
+  if (state.streaming && targetConv && state.generatingConvs.has(targetConv)) {
+    localStorage.setItem(genKey(targetConv), targetConv)
+    localStorage.setItem(textKey(targetConv), state.currentText)
   }
   // 主窗口 state 与分离窗口 state 独立(各自 webview 独立 JS context,
   // stores/ai.ts 模块级单例仅在同 webview 内共享),清主窗口 state 不影响分离窗口生成态。
-  // 分离窗口接管生成后,主窗口不应再持生成态残留(防重开面板时 UI 显生成中幽灵/进度条)。
+  // 分离窗口接管生成后,主窗口不应再持该会话生成态残留(防重开面板时 UI 显生成中幽灵/进度条)。
+  // F-09:仅从 Set 移除该 conv(其他会话可能仍在生成),不全局清空。
   // watchdog 在主窗口 AiChat 卸载(App.vue v-if detached)→ stopListener → clearStreamWatchdog 时已清,
   // 此处仅清内存 state 视觉残留;localStorage 快照保留供 resumeInDetached 恢复。
   state.streaming = false
-  state.generatingConvId = null
-  const convId = state.activeConversationId
-  const sep = convId ? `?conv=${encodeURIComponent(convId)}` : ''
+  if (targetConv) state.generatingConvs.delete(targetConv)
+  const sep = targetConv ? `?conv=${encodeURIComponent(targetConv)}` : ''
   const url = window.location.origin + window.location.pathname + '#/ai-detached' + sep
-  const win = new WebviewWindow('ai-detached', {
+  const win = new WebviewWindow(label, {
     url,
     title: 'DevFlow AI',
     width: 600, // U-260618: 加宽(原 520 偏窄),与吸附态 AI_DOCK_WIDTH 一致
@@ -68,30 +93,48 @@ async function detachPanel() {
   state.detached = true
 }
 
-/** 关闭分离窗口并回到内嵌面板(主窗口侧调用) */
+/** 关闭分离窗口并回到内嵌面板(主窗口侧调用)。
+ *  F-09:多会话并发下可能存在多个 detached 窗口,全部关闭并清各自 per-conv 快照。 */
 async function reattachPanel() {
   stopFollowMain()
   const { WebviewWindow } = await import('@tauri-apps/api/webviewWindow')
-  const win = await WebviewWindow.getByLabel('ai-detached')
-  if (win) {
-    await win.close()
+  // 关闭所有 ai-detached-* 前缀的窗口(含旧版单 label 'ai-detached' 兼容)
+  const all = await WebviewWindow.getAll()
+  for (const w of all) {
+    const lbl = w.label
+    if (lbl === 'ai-detached' || lbl.startsWith(DETACHED_LABEL_PREFIX)) {
+      try { await w.close() } catch { /* 忽略单个窗口关闭失败 */ }
+    }
   }
   state.detached = false
   state.docked = false
   state.panelOpen = true
   persistUiState()
-  localStorage.removeItem('df-ai-gen')
-  localStorage.removeItem('df-ai-text')
+  // F-09:清所有 per-conv 快照(分离窗口已全关,快照无消费方)
+  cleanupAllDetachedSnapshots()
+}
+
+/** 清理所有 df-ai-gen-* / df-ai-text-* 快照(分离窗口全关 / 整轮收尾时调用) */
+function cleanupAllDetachedSnapshots(): void {
+  const keysToRemove: string[] = []
+  for (let i = localStorage.length - 1; i >= 0; i--) {
+    const k = localStorage.key(i)
+    if (!k) continue
+    if (k.startsWith(GEN_KEY_PREFIX) || k.startsWith(TEXT_KEY_PREFIX) || k === 'df-ai-gen' || k === 'df-ai-text') {
+      keysToRemove.push(k)
+    }
+  }
+  for (const k of keysToRemove) localStorage.removeItem(k)
 }
 
 /**
  * 重建生成中态(分离窗口 resumeInDetached 与主面板 onMounted 恢复共用)。
  *
- * 读 localStorage df-ai-gen/df-ai-text,核对后端 ai_is_generating 真值后重建:
- * 1. state.currentText = df-ai-text(已生成文本)
+ * 读 localStorage df-ai-gen-${convId}/df-ai-text-${convId}(F-09 per-conv key),核对后端 ai_is_generating 真值后重建:
+ * 1. state.currentText = df-ai-text-${convId}(已生成文本)
  * 2. push 占位 assistant 气泡(content='')
  * 3. state.streaming = true
- * 4. state.generatingConvId = df-ai-gen
+ * 4. state.generatingConvs.add(df-ai-gen)
  *
  * 幂等:若 state.streaming 已是 true(已恢复过/正在生成),直接返回不重复 push。
  * 这对主面板刷新场景至关重要:detachPanel 时主窗口 state 已被清 streaming=false
@@ -103,17 +146,19 @@ async function reattachPanel() {
  *
  * @returns true=已重建;false=未恢复(无快照/后端未生成/核对失败/已生成中)
  */
-export async function restoreGeneratingState(opts?: { fromMainPanel?: boolean }): Promise<boolean> {
+export async function restoreGeneratingState(opts?: { fromMainPanel?: boolean; convId?: string }): Promise<boolean> {
   // 幂等:已生成中态不再重建(防主面板 + 分离窗口共享 state 时双重恢复;
   // 主面板与分离窗口 state 各自独立,但稳妥起见仍守卫)
   if (state.streaming) return false
   const fromMainPanel = opts?.fromMainPanel ?? false
-  // 主面板刷新场景:detachPanel 未触发 → df-ai-gen 不存在。
+  // 主面板刷新场景:detachPanel 未触发 → df-ai-gen-* 不存在。
   // 此时用 state.activeConversationId 作为生成中会话(刷新前 loadConversations 已恢复),
-  // 无 df-ai-text 快照 → currentText 从空开始(刷新前已生成部分丢失,刷新固有代价;
+  // 无 df-ai-text-* 快照 → currentText 从空开始(刷新前已生成部分丢失,刷新固有代价;
   // 后端后续 AiTextDelta 仍会追加,核心是恢复 streaming 态 + 占位气泡消除假死)。
-  // 分离窗口场景:读 detachPanel 写入的 df-ai-gen 快照。
-  const gen = fromMainPanel ? state.activeConversationId : localStorage.getItem('df-ai-gen')
+  // 分离窗口场景:读 detachPanel 写入的 df-ai-gen-${convId} 快照(F-09 per-conv key)。
+  const gen = fromMainPanel
+    ? state.activeConversationId
+    : (opts?.convId && localStorage.getItem(genKey(opts.convId))) || localStorage.getItem('df-ai-gen')
   if (!gen) return false
   // 核对后端 ai_is_generating 真值
   // F-260616-09 B 批4(决策 e):传 gen(目标 conv)精确查,不读全局单值。
@@ -127,15 +172,19 @@ export async function restoreGeneratingState(opts?: { fromMainPanel?: boolean })
   if (!backendGenerating) {
     // 后端已不再生成,清残留快照(仅分离窗口快照路径),不重建
     if (!fromMainPanel) {
+      if (opts?.convId) {
+        localStorage.removeItem(genKey(opts.convId))
+        localStorage.removeItem(textKey(opts.convId))
+      }
       localStorage.removeItem('df-ai-gen')
       localStorage.removeItem('df-ai-text')
     }
     return false
   }
   // 恢复已生成文本并补占位,后续 delta 继续追加
-  // 主面板无 df-ai-text 快照,保持 currentText 当前值(空),仅靠占位气泡 + streaming 态接收后续 delta
+  // 主面板无 df-ai-text-* 快照,保持 currentText 当前值(空),仅靠占位气泡 + streaming 态接收后续 delta
   if (!fromMainPanel) {
-    state.currentText = localStorage.getItem('df-ai-text') || ''
+    state.currentText = (opts?.convId && localStorage.getItem(textKey(opts.convId))) || localStorage.getItem('df-ai-text') || ''
   }
   state.messages.push({
     id: `ai-${nextMsgId()}`,
@@ -144,7 +193,7 @@ export async function restoreGeneratingState(opts?: { fromMainPanel?: boolean })
     timestamp: Date.now(),
   })
   state.streaming = true
-  state.generatingConvId = gen
+  state.generatingConvs.add(gen)
   return true
 }
 
@@ -152,18 +201,28 @@ export async function restoreGeneratingState(opts?: { fromMainPanel?: boolean })
 async function resumeInDetached(convId: string | null) {
   // R5: 不自动 switchConversation —— 分离窗口可看历史列表,但不主动覆盖主窗口 activeConversationId
   //     (避免主窗口期间发消息落错会话)。若需切换会话,由用户在分离窗口显式操作触发。
-  void convId
-  await restoreGeneratingState()
+  // F-09: 透传 convId 给 restoreGeneratingState,定位正确的 per-conv 快照 key。
+  await restoreGeneratingState({ convId: convId || undefined })
 }
 
-/** 关闭分离窗口自身(分离窗口侧调用) */
+/** 关闭分离窗口自身(分离窗口侧调用)。
+ *  F-09:从当前 webview 的 label 反推 convId,清自己的 per-conv 快照。 */
 async function closeDetachedWindow() {
   state.docked = false
   stopFollowMain()
-  localStorage.removeItem('df-ai-gen')
-  localStorage.removeItem('df-ai-text')
   const { getCurrentWebviewWindow } = await import('@tauri-apps/api/webviewWindow')
-  await getCurrentWebviewWindow().close()
+  const currentWin = getCurrentWebviewWindow()
+  const lbl = currentWin.label
+  // per-conv label 'ai-detached-<convId>' → 清对应快照;旧 label 'ai-detached' → 清遗留单 key
+  if (lbl.startsWith(DETACHED_LABEL_PREFIX)) {
+    const convId = lbl.slice(DETACHED_LABEL_PREFIX.length)
+    localStorage.removeItem(genKey(convId))
+    localStorage.removeItem(textKey(convId))
+  } else {
+    localStorage.removeItem('df-ai-gen')
+    localStorage.removeItem('df-ai-text')
+  }
+  await currentWin.close()
 }
 
 /** 吸附/取消吸附：AI 窗口跟随主窗口右侧 */
diff --git a/src/i18n/en/aiChat.ts b/src/i18n/en/aiChat.ts
index c9e554e..4472cc1 100644
--- a/src/i18n/en/aiChat.ts
+++ b/src/i18n/en/aiChat.ts
@@ -4,6 +4,7 @@ export default {
     sidebarTitle: 'Chats',
     newConversation: 'New chat',
     doubleClickToRename: 'Double-click to rename',
+    generating: 'Generating…',
     archive: 'Archive',
     unarchive: 'Unarchive',
     pinConversation: 'Pin',
diff --git a/src/i18n/zh-CN/aiChat.ts b/src/i18n/zh-CN/aiChat.ts
index 8ee2944..c8265ba 100644
--- a/src/i18n/zh-CN/aiChat.ts
+++ b/src/i18n/zh-CN/aiChat.ts
@@ -4,6 +4,7 @@ export default {
     sidebarTitle: '对话',
     newConversation: '新对话',
     doubleClickToRename: '双击重命名',
+    generating: '生成中…',
     archive: '归档',
     unarchive: '取消归档',
     pinConversation: '置顶',
diff --git a/src/stores/ai.ts b/src/stores/ai.ts
index 08d14f6..365193b 100644
--- a/src/stores/ai.ts
+++ b/src/stores/ai.ts
@@ -63,8 +63,11 @@ export const state = reactive({
   streaming: false,
   currentText: '',
   pendingApprovals: [] as AiToolCallInfo[],
-  // 正在生成的对话 id:生成中切走时用于路由,后台事件不污染当前视图
-  generatingConvId: null as string | null,
+  // 正在生成的会话集合(F-09 多会话并发):后端 per-conv 已支持多会话同时生成,
+  // 前端用 Set 表达"多会话同时生成"态。生成中切走时用于路由,后台事件不污染当前视图。
+  // isGenerating(convId)/addGenerating/removeGenerating helper 经 useAiStore 暴露。
+  // 单会话场景行为不变(Set 含 0 或 1 元素)。
+  generatingConvs: new Set<string>(),
   providers: [] as AiProviderConfig[],
   activeProvider: null as string | null,
   panelOpen: true,
@@ -185,6 +188,23 @@ const filteredConversations = computed<AiConversationSummary[] | null>(() => {
     .sort((a, b) => (b.updated_at > a.updated_at ? 1 : b.updated_at < a.updated_at ? -1 : 0))
 })
 
+/**
+ * F-09 多会话并发:生成态 Set helper。
+ *
+ * Vue 3 reactive 对 Set 的 has/add/delete 均有 proxy 跟踪,在 computed/template
+ * 内调用 isGenerating(convId) 会建立响应式依赖,Set 变更时自动触发更新。
+ * 单会话场景:Set 含 0 或 1 元素,行为与原单值 generatingConvId 等价。
+ */
+function addGenerating(convId: string): void {
+  state.generatingConvs.add(convId)
+}
+function removeGenerating(convId: string): void {
+  state.generatingConvs.delete(convId)
+}
+function isGenerating(convId: string | null | undefined): boolean {
+  return !!convId && state.generatingConvs.has(convId)
+}
+
 /**
  * AI Store 统一入口 — 返回单例 state + 全部方法。
  *
@@ -197,6 +217,10 @@ export function useAiStore() {
   return {
     state,
     filteredConversations,
+    // F-09: 生成态 Set helper(替代单值 generatingConvId 的读写)
+    addGenerating,
+    removeGenerating,
+    isGenerating,
     ...useAiEvents(),
     ...useAiStream(),
     ...useAiSend(),