diff --git a/src/components/appearance-provider.tsx b/src/components/appearance-provider.tsx
index 6ca6f137ad..813edbb4a9 100644
--- a/src/components/appearance-provider.tsx
+++ b/src/components/appearance-provider.tsx
@@ -32,6 +32,7 @@ import {
   STORAGE_KEY_THEME_COLOR,
   STORAGE_KEY_ZOOM_LEVEL,
   STORAGE_KEY_WELCOME_QUICK_ACTIONS,
+  STORAGE_KEY_KEEP_OPENED_CONVERSATIONS,
   STORAGE_KEY_UI_FONT,
   STORAGE_KEY_UI_FONT_CUSTOM,
   STORAGE_KEY_UI_FONT_STACK,
@@ -117,6 +118,9 @@ type AppearanceContextValue = {
   /** 新会话欢迎页是否显示「模式选择区域」（QuickActions 快捷卡片），默认开启 */
   showWelcomeQuickActions: boolean
   setShowWelcomeQuickActions: (on: boolean) => void
+  /** 打开的会话是否各占一个标签页（关闭预览标签页的「就地替换」），默认关闭 */
+  keepOpenedConversations: boolean
+  setKeepOpenedConversations: (on: boolean) => void
   /** 界面字体（普通组件，驱动 --font-sans） */
   uiFont: FontSelection
   setUiFont: (id: string, custom?: string) => void
@@ -370,6 +374,13 @@ export function AppearanceProvider({
   const [showWelcomeQuickActions, setShowWelcomeQuickActionsState] =
     useState<boolean>(() => readBool(STORAGE_KEY_WELCOME_QUICK_ACTIONS, true))
 
+  // 打开的会话是否保留各自的标签页：默认关闭，键缺失即回退为预览标签页的历史行为。
+  // 真正消费它的是 tab store（在 openTab 里直接读同一个键），这里只是设置面板的回显态。
+  const [keepOpenedConversations, setKeepOpenedConversationsState] =
+    useState<boolean>(() =>
+      readBool(STORAGE_KEY_KEEP_OPENED_CONVERSATIONS, false)
+    )
+
   // 字体偏好的初始值从 localStorage 读 id/custom（视觉已由 inline 脚本就位，
   // 这里只是回填选中态，不会造成闪烁）。
   const [uiFont, setUiFontState] = useState<FontSelection>(() =>
@@ -519,6 +530,11 @@ export function AppearanceProvider({
     persist(STORAGE_KEY_WELCOME_QUICK_ACTIONS, on ? "1" : "0")
   }, [])
 
+  const setKeepOpenedConversations = useCallback((on: boolean) => {
+    setKeepOpenedConversationsState(on)
+    persist(STORAGE_KEY_KEEP_OPENED_CONVERSATIONS, on ? "1" : "0")
+  }, [])
+
   const setUiFont = useCallback((id: string, custom = "") => {
     setUiFontState({ id, custom })
     const stack = resolveFontStack(id, custom, "sans")
@@ -955,6 +971,11 @@ export function AppearanceProvider({
           readBool(STORAGE_KEY_WELCOME_QUICK_ACTIONS, true)
         )
       }
+      if (e.key === STORAGE_KEY_KEEP_OPENED_CONVERSATIONS) {
+        setKeepOpenedConversationsState(
+          readBool(STORAGE_KEY_KEEP_OPENED_CONVERSATIONS, false)
+        )
+      }
       if (e.key && FONT_KEYS.has(e.key)) {
         rehydrateFonts()
       }
@@ -1059,6 +1080,8 @@ export function AppearanceProvider({
         setZoomLevel,
         showWelcomeQuickActions,
         setShowWelcomeQuickActions,
+        keepOpenedConversations,
+        setKeepOpenedConversations,
         uiFont,
         setUiFont,
         editorFont,
diff --git a/src/components/settings/appearance-settings.tsx b/src/components/settings/appearance-settings.tsx
index c5b9d00d8e..cd0f547959 100644
--- a/src/components/settings/appearance-settings.tsx
+++ b/src/components/settings/appearance-settings.tsx
@@ -1,6 +1,13 @@
 "use client"
 
-import { LayoutGrid, Monitor, Moon, Sun, Type } from "lucide-react"
+import {
+  LayoutGrid,
+  Monitor,
+  Moon,
+  PanelsTopLeft,
+  Sun,
+  Type,
+} from "lucide-react"
 import { useTranslations } from "next-intl"
 import { useTheme } from "next-themes"
 import { ScrollArea } from "@/components/ui/scroll-area"
@@ -16,6 +23,7 @@ import {
   useThemeColor,
   useZoomLevel,
   useWelcomeQuickActions,
+  useKeepOpenedConversations,
 } from "@/hooks/use-appearance"
 import { cn } from "@/lib/utils"
 import {
@@ -40,6 +48,8 @@ export function AppearanceSettings() {
   const { zoomLevel, setZoomLevel } = useZoomLevel()
   const { showWelcomeQuickActions, setShowWelcomeQuickActions } =
     useWelcomeQuickActions()
+  const { keepOpenedConversations, setKeepOpenedConversations } =
+    useKeepOpenedConversations()
 
   const resolvedThemeLabel =
     resolvedTheme === "dark"
@@ -214,6 +224,30 @@ export function AppearanceSettings() {
         {/* ===== Workspace background ===== */}
         <WorkspaceBackgroundSection />
 
+        {/* ===== Conversation tabs ===== */}
+        <section className="rounded-xl border bg-card p-4 space-y-4">
+          <div className="flex items-center gap-2">
+            <PanelsTopLeft className="h-4 w-4 text-muted-foreground" />
+            <h2 className="text-sm font-semibold">
+              {t("conversationTabs.sectionTitle")}
+            </h2>
+          </div>
+
+          <p className="text-xs text-muted-foreground leading-5">
+            {t("conversationTabs.sectionDescription")}
+          </p>
+
+          <label className="flex items-center gap-2">
+            <Switch
+              checked={keepOpenedConversations}
+              onCheckedChange={setKeepOpenedConversations}
+            />
+            <span className="text-xs text-muted-foreground">
+              {t("conversationTabs.keepOpened")}
+            </span>
+          </label>
+        </section>
+
         {/* ===== New conversation — mode selection area ===== */}
         <section className="rounded-xl border bg-card p-4 space-y-4">
           <div className="flex items-center gap-2">
diff --git a/src/contexts/tab-context.test.tsx b/src/contexts/tab-context.test.tsx
index d0587b4512..fdccfd9584 100644
--- a/src/contexts/tab-context.test.tsx
+++ b/src/contexts/tab-context.test.tsx
@@ -1,6 +1,6 @@
 import { act, render, screen, waitFor } from "@testing-library/react"
 import { useEffect } from "react"
-import { beforeEach, describe, expect, it, vi } from "vitest"
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest"
 import { TabProvider, useTabContext } from "@/contexts/tab-context"
 import { CONVERSATION_CHANGED_EVENT, TABS_CHANGED_EVENT } from "@/lib/types"
 import type {
@@ -25,6 +25,7 @@ import {
   type OpenedDraftTarget,
 } from "@/stores/tab-store"
 import { leafIds } from "@/lib/tab-group-layout"
+import { STORAGE_KEY_KEEP_OPENED_CONVERSATIONS } from "@/lib/appearance-script"
 import {
   buildNewConversationDraftStorageKey,
   loadMessageInputDraftV2,
@@ -2718,6 +2719,161 @@ describe("TabProvider tab groups", () => {
     })
   })
 
+  // A preview tab is a slot the next open takes over, so a conversation opened
+  // only to read it is thrown away by whatever the user opens next. "Keep
+  // opened conversations" (Appearance settings) turns that slot off. It is off
+  // by default, so the preference is the only thing that changes any of this.
+  describe("keep opened conversations", () => {
+    const preferKeepingTabs = (on: boolean) => {
+      if (on) localStorage.setItem(STORAGE_KEY_KEEP_OPENED_CONVERSATIONS, "1")
+      else localStorage.removeItem(STORAGE_KEY_KEEP_OPENED_CONVERSATIONS)
+    }
+
+    afterEach(() => preferKeepingTabs(false))
+
+    /** `[id, isPinned]` for each tab the group holds, in strip order. */
+    const stripState = (groupId: string) =>
+      store()
+        .rawTabs.filter((tab) => groupOfId(tab.id) === groupId)
+        .map((tab) => [tab.id, tab.isPinned])
+
+    it("gives every opened conversation a tab of its own", async () => {
+      preferKeepingTabs(true)
+      await renderWithTabs([tabItem(1, 1, true)])
+      const home = leaves()[0]
+
+      act(() => {
+        store().openTab(1, 2, "codex", false, "Second")
+      })
+      act(() => {
+        store().openTab(1, 3, "codex", false, "Third")
+      })
+
+      // Pinned rather than merely spared: the strip sets a preview in oblique
+      // type, and a tab nothing will replace must not wear that mark.
+      expect(stripState(home)).toEqual([
+        ["conv-1-codex-1", true],
+        ["conv-1-codex-2", true],
+        ["conv-1-codex-3", true],
+      ])
+      expect(store().activeTabId).toBe("conv-1-codex-3")
+    })
+
+    it("still replaces the preview while the preference is off", async () => {
+      await renderWithTabs([tabItem(1, 1, true)])
+      const home = leaves()[0]
+
+      act(() => {
+        store().openTab(1, 2, "codex", false, "Second")
+      })
+      act(() => {
+        store().openTab(1, 3, "codex", false, "Third")
+      })
+
+      expect(stripState(home)).toEqual([
+        ["conv-1-codex-1", true],
+        ["conv-1-codex-3", false],
+      ])
+      expect(store().activeTabId).toBe("conv-1-codex-3")
+    })
+
+    it("focuses a conversation it already holds instead of opening it twice", async () => {
+      preferKeepingTabs(true)
+      await renderWithTabs([tabItem(1, 1, true)])
+      const home = leaves()[0]
+
+      act(() => {
+        store().openTab(1, 2, "codex", false, "Second")
+      })
+      act(() => {
+        store().switchTab("conv-1-codex-1")
+      })
+      act(() => {
+        store().openTab(1, 2, "codex", false, "Second")
+      })
+
+      expect(stripState(home)).toEqual([
+        ["conv-1-codex-1", true],
+        ["conv-1-codex-2", true],
+      ])
+      expect(store().activeTabId).toBe("conv-1-codex-2")
+    })
+
+    it("leaves the double-click pin doing its job while the preference is off", async () => {
+      await renderWithTabs([tabItem(1, 1, true)])
+      const home = leaves()[0]
+
+      // A double click in the sidebar is the single-click open followed by the
+      // pinning one, so the preview it just parked is the tab it promotes.
+      act(() => {
+        store().openTab(1, 2, "codex", false, "Second")
+      })
+      act(() => {
+        store().openTab(1, 2, "codex", true, "Second")
+      })
+      act(() => {
+        store().openTab(1, 3, "codex", false, "Third")
+      })
+
+      expect(stripState(home)).toEqual([
+        ["conv-1-codex-1", true],
+        ["conv-1-codex-2", true],
+        ["conv-1-codex-3", false],
+      ])
+    })
+
+    it("keeps every pane of a tiled group", async () => {
+      preferKeepingTabs(true)
+      await renderWithTabs([tabItem(1, 1, true)])
+      const home = leaves()[0]
+
+      act(() => {
+        store().toggleGroupTile(home)
+      })
+      act(() => {
+        store().openTab(1, 2, "codex", false, "Second")
+      })
+      act(() => {
+        store().openTab(1, 3, "codex", false, "Third")
+      })
+
+      expect(stripState(home)).toEqual([
+        ["conv-1-codex-1", true],
+        ["conv-1-codex-2", true],
+        ["conv-1-codex-3", true],
+      ])
+    })
+
+    it("keeps the tabs of every group, not just the focused one", async () => {
+      preferKeepingTabs(true)
+      await renderWithTabs([tabItem(1, 1, true), tabItem(1, 2)])
+      const home = leaves()[0]
+
+      act(() => {
+        store().splitTab("conv-1-codex-2", "right", { move: true })
+      })
+      const g1 = newLeafBeside(home)
+      act(() => {
+        store().openTab(1, 3, "codex", false, "Third")
+      })
+      act(() => {
+        store().switchTab("conv-1-codex-1")
+      })
+      act(() => {
+        store().openTab(1, 4, "codex", false, "Fourth")
+      })
+
+      expect(stripState(home)).toEqual([
+        ["conv-1-codex-1", true],
+        ["conv-1-codex-4", true],
+      ])
+      expect(stripState(g1)).toEqual([
+        ["conv-1-codex-2", true],
+        ["conv-1-codex-3", true],
+      ])
+    })
+  })
+
   // The unmount classifier that decides whether a vanishing conversation view
   // keeps its ACP connection. Getting this wrong in either direction is
   // expensive: too broad leaks viewer subscriptions (the idle sweep skips
diff --git a/src/hooks/use-appearance.ts b/src/hooks/use-appearance.ts
index 6468b07e02..c681108b16 100644
--- a/src/hooks/use-appearance.ts
+++ b/src/hooks/use-appearance.ts
@@ -31,6 +31,13 @@ export function useWelcomeQuickActions() {
   return { showWelcomeQuickActions, setShowWelcomeQuickActions }
 }
 
+/** 语义化包装：打开的会话是否各自保留一个标签页（关闭预览标签页的就地替换） */
+export function useKeepOpenedConversations() {
+  const { keepOpenedConversations, setKeepOpenedConversations } =
+    useAppearance()
+  return { keepOpenedConversations, setKeepOpenedConversations }
+}
+
 /** 界面字体（普通组件）。stack 已解析，可直接用于 style 或 CSS 变量。 */
 export function useUiFont() {
   const { uiFont, setUiFont } = useAppearance()
diff --git a/src/i18n/messages/ar.json b/src/i18n/messages/ar.json
index 66c1e78eca..a93baa00ef 100644
--- a/src/i18n/messages/ar.json
+++ b/src/i18n/messages/ar.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "تنطبق الحروف المتصلة في الطرفية على خطوط البرمجة المضمّنة فقط.",
       "preview": "معاينة"
     },
+    "conversationTabs": {
+      "sectionTitle": "علامات تبويب المحادثات",
+      "sectionDescription": "النقر يفتح علامة تبويب تبقى حتى تغلقها، بدلاً من أن تحل محلها المحادثة التالية التي تفتحها.",
+      "keepOpened": "الإبقاء على المحادثات المفتوحة"
+    },
     "welcomePanel": {
       "sectionTitle": "منطقة اختيار الوضع",
       "sectionDescription": "بطاقات الاختصار «تطوير الكود / الأعمال المكتبية» التي تظهر أعلى مربع الإدخال في صفحة المحادثة الجديدة.",
diff --git a/src/i18n/messages/de.json b/src/i18n/messages/de.json
index 791fd785d6..d9612a5e50 100644
--- a/src/i18n/messages/de.json
+++ b/src/i18n/messages/de.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "Terminal-Ligaturen gelten nur für mitgelieferte Programmierschriftarten.",
       "preview": "Vorschau"
     },
+    "conversationTabs": {
+      "sectionTitle": "Konversations-Tabs",
+      "sectionDescription": "Ein Klick öffnet einen Tab, der bleibt, bis du ihn schließt, statt von der nächsten geöffneten Konversation ersetzt zu werden.",
+      "keepOpened": "Geöffnete Konversationen behalten"
+    },
     "welcomePanel": {
       "sectionTitle": "Modusauswahlbereich",
       "sectionDescription": "Die Shortcut-Karten „Code-Entwicklung / Büroarbeit“ über dem Eingabefeld auf der Seite für eine neue Konversation.",
diff --git a/src/i18n/messages/en.json b/src/i18n/messages/en.json
index ecab7562ac..98980e6d74 100644
--- a/src/i18n/messages/en.json
+++ b/src/i18n/messages/en.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "Terminal ligatures apply only to bundled coding fonts.",
       "preview": "Preview"
     },
+    "conversationTabs": {
+      "sectionTitle": "Conversation tabs",
+      "sectionDescription": "A click opens a tab that stays until you close it, instead of being replaced by the next conversation you open.",
+      "keepOpened": "Keep opened conversations"
+    },
     "welcomePanel": {
       "sectionTitle": "Mode selection area",
       "sectionDescription": "The Code Development / Office Work shortcut cards shown above the composer on the new conversation page.",
diff --git a/src/i18n/messages/es.json b/src/i18n/messages/es.json
index db03d9122f..0ac91a0960 100644
--- a/src/i18n/messages/es.json
+++ b/src/i18n/messages/es.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "Las ligaduras del terminal solo se aplican a las fuentes de programación incluidas.",
       "preview": "Vista previa"
     },
+    "conversationTabs": {
+      "sectionTitle": "Pestañas de conversación",
+      "sectionDescription": "Un clic abre una pestaña que permanece hasta que la cierras, en lugar de ser reemplazada por la siguiente conversación que abras.",
+      "keepOpened": "Mantener las conversaciones abiertas"
+    },
     "welcomePanel": {
       "sectionTitle": "Área de selección de modo",
       "sectionDescription": "Las tarjetas de acceso rápido «Desarrollo de código / Ofimática» que se muestran sobre el editor en la página de nueva conversación.",
diff --git a/src/i18n/messages/fr.json b/src/i18n/messages/fr.json
index 1a4d49f6e2..a726cada1a 100644
--- a/src/i18n/messages/fr.json
+++ b/src/i18n/messages/fr.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "Les ligatures du terminal ne s’appliquent qu’aux polices de programmation intégrées.",
       "preview": "Aperçu"
     },
+    "conversationTabs": {
+      "sectionTitle": "Onglets de conversation",
+      "sectionDescription": "Un clic ouvre un onglet qui reste jusqu’à ce que vous le fermiez, au lieu d’être remplacé par la conversation suivante que vous ouvrez.",
+      "keepOpened": "Conserver les conversations ouvertes"
+    },
     "welcomePanel": {
       "sectionTitle": "Zone de sélection du mode",
       "sectionDescription": "Les cartes de raccourci « Développement / Bureautique » affichées au-dessus du champ de saisie sur la page de nouvelle conversation.",
diff --git a/src/i18n/messages/ja.json b/src/i18n/messages/ja.json
index fbe7afddbf..989521df4d 100644
--- a/src/i18n/messages/ja.json
+++ b/src/i18n/messages/ja.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "ターミナルの合字は内蔵のコーディングフォントにのみ適用されます。",
       "preview": "プレビュー"
     },
+    "conversationTabs": {
+      "sectionTitle": "会話タブ",
+      "sectionDescription": "クリックで開いたタブは、次に開いた会話に置き換えられることなく、閉じるまで残ります。",
+      "keepOpened": "開いた会話を残す"
+    },
     "welcomePanel": {
       "sectionTitle": "モード選択エリア",
       "sectionDescription": "新しい会話ページで入力欄の上に表示される「コード開発 / 日常業務」のショートカットカードです。",
diff --git a/src/i18n/messages/ko.json b/src/i18n/messages/ko.json
index f23e38116f..7d56b04ab0 100644
--- a/src/i18n/messages/ko.json
+++ b/src/i18n/messages/ko.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "터미널 합자는 내장 코딩 글꼴에만 적용됩니다.",
       "preview": "미리 보기"
     },
+    "conversationTabs": {
+      "sectionTitle": "대화 탭",
+      "sectionDescription": "클릭으로 연 탭은 다음에 여는 대화로 바뀌지 않고 닫을 때까지 그대로 유지됩니다.",
+      "keepOpened": "연 대화 유지"
+    },
     "welcomePanel": {
       "sectionTitle": "모드 선택 영역",
       "sectionDescription": "새 대화 페이지에서 입력창 위에 표시되는 '코드 개발 / 일상 업무' 바로가기 카드입니다.",
diff --git a/src/i18n/messages/pt.json b/src/i18n/messages/pt.json
index d334c38757..43c0b84185 100644
--- a/src/i18n/messages/pt.json
+++ b/src/i18n/messages/pt.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "As ligaduras do terminal aplicam-se apenas às fontes de programação incluídas.",
       "preview": "Pré-visualização"
     },
+    "conversationTabs": {
+      "sectionTitle": "Abas de conversa",
+      "sectionDescription": "Um clique abre uma aba que permanece até ser fechada, em vez de ser substituída pela próxima conversa aberta.",
+      "keepOpened": "Manter as conversas abertas"
+    },
     "welcomePanel": {
       "sectionTitle": "Área de seleção de modo",
       "sectionDescription": "Os cartões de atalho «Desenvolvimento / Escritório» exibidos acima do campo de entrada na página de nova conversa.",
diff --git a/src/i18n/messages/zh-CN.json b/src/i18n/messages/zh-CN.json
index e42916daf2..6a7d38c6b1 100644
--- a/src/i18n/messages/zh-CN.json
+++ b/src/i18n/messages/zh-CN.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "终端连字仅对内置编程字体生效。",
       "preview": "预览"
     },
+    "conversationTabs": {
+      "sectionTitle": "会话标签页",
+      "sectionDescription": "单击打开的标签页会一直保留到手动关闭，而不会被下一个打开的会话就地替换。",
+      "keepOpened": "保留已打开的会话"
+    },
     "welcomePanel": {
       "sectionTitle": "模式选择区域",
       "sectionDescription": "新会话页面输入框上方显示的「代码开发 / 日常办公」快捷卡片区域。",
diff --git a/src/i18n/messages/zh-TW.json b/src/i18n/messages/zh-TW.json
index d58afc27ba..e8bfed87a8 100644
--- a/src/i18n/messages/zh-TW.json
+++ b/src/i18n/messages/zh-TW.json
@@ -168,6 +168,11 @@
       "terminalLigaturesHint": "終端機連字僅對內建程式字型生效。",
       "preview": "預覽"
     },
+    "conversationTabs": {
+      "sectionTitle": "會話標籤頁",
+      "sectionDescription": "單擊開啟的標籤頁會一直保留到手動關閉，而不會被下一個開啟的會話就地取代。",
+      "keepOpened": "保留已開啟的會話"
+    },
     "welcomePanel": {
       "sectionTitle": "模式選擇區域",
       "sectionDescription": "新會話頁面輸入框上方顯示的「程式開發 / 日常辦公」快捷卡片區域。",
diff --git a/src/lib/appearance-script.ts b/src/lib/appearance-script.ts
index e47c8c7c2a..7883661537 100644
--- a/src/lib/appearance-script.ts
+++ b/src/lib/appearance-script.ts
@@ -18,6 +18,15 @@ export const STORAGE_KEY_ZOOM_LEVEL = "codeg-zoom-level"
 // 缺省即回退为开启（保持历史行为）；仅在欢迎态客户端渲染，无需预水合。
 export const STORAGE_KEY_WELCOME_QUICK_ACTIONS = "codeg-welcome-quick-actions"
 
+// Whether an opened conversation keeps its own tab instead of taking the
+// group's single preview slot. Missing key falls back to preview tabs (the
+// historical behavior). Read by the tab store at open time as well as by the
+// Provider, so the settings window and the workspace window share one value
+// through localStorage. Nothing renders from it on the first frame, so it
+// needs no pre-hydration.
+export const STORAGE_KEY_KEEP_OPENED_CONVERSATIONS =
+  "codeg-keep-opened-conversations"
+
 // 字体偏好（界面 / 编辑器 / 终端）。
 // 只有界面字体需要 *_STACK（已解析的 CSS font-family 栈），供 inline 脚本零依赖地
 // 预水合写入 --font-sans；编辑器/终端字体只走各自的 Monaco/xterm 选项，水合后才挂载，
diff --git a/src/stores/tab-store.ts b/src/stores/tab-store.ts
index 0d76967df9..be1943c652 100644
--- a/src/stores/tab-store.ts
+++ b/src/stores/tab-store.ts
@@ -36,6 +36,7 @@ import {
   sweepOrphanDraftKeys,
 } from "@/lib/message-input-draft"
 import { discardAskSelectionPrompts } from "@/lib/ask-selection-handoff"
+import { STORAGE_KEY_KEEP_OPENED_CONVERSATIONS } from "@/lib/appearance-script"
 import {
   batchCloseSlots,
   pushClosedTab,
@@ -328,6 +329,26 @@ const TILE_MODE_STORAGE_KEY = "workspace:tile-mode"
  *  flags), keyed by canonical tab ids. See `persistGroupState`. */
 const TAB_GROUPS_STORAGE_KEY = "workspace:tab-groups:v1"
 
+/**
+ * "Keep opened conversations" (Appearance settings): when it is on, opening a
+ * conversation is never a preview — it takes a tab of its own and keeps it
+ * until the user closes it. Off by default, which is the preview-tab behavior
+ * this app has always had.
+ *
+ * Read per open rather than cached: appearance settings live in their own
+ * window, so localStorage is what the two windows share, and reading it at the
+ * decision point means a change takes effect on the very next click without
+ * any cross-window plumbing.
+ */
+function keepOpenedConversations(): boolean {
+  if (typeof window === "undefined") return false
+  try {
+    return localStorage.getItem(STORAGE_KEY_KEEP_OPENED_CONVERSATIONS) === "1"
+  } catch {
+    return false
+  }
+}
+
 /** Per-window/session identity stamped on every tab save and echoed back on
  *  `tabs://changed`, so this client ignores its own broadcast (echo
  *  suppression). Regenerated each load — it identifies the window for echo
@@ -1155,6 +1176,13 @@ export const useTabStore = create<TabStoreState>()((set, get) => ({
       ) || runtime.labels.untitledConversation
 
     const tabId = makeConversationTabId(folderId, agentType, conversationId)
+    // A conversation the user asked to keep is not a preview at all, so it
+    // opens exactly like a pinned open: its own slot, and no preview victim is
+    // looked for below. Being genuinely pinned is the point — the tab strip
+    // renders a preview in oblique type, and a tab that will never be replaced
+    // must not wear that mark (nor become replaceable again if the preference
+    // is later turned back off).
+    const pinned = pin || keepOpenedConversations()
     const newTab: TabItemInternal = {
       id: tabId,
       kind: "conversation",
@@ -1162,10 +1190,10 @@ export const useTabStore = create<TabStoreState>()((set, get) => ({
       conversationId,
       agentType,
       title: resolvedTitle,
-      isPinned: pin,
+      isPinned: pinned,
     }
 
-    if (pin) {
+    if (pinned) {
       set({
         rawTabs: insertTab(prevState.rawTabs, newTab, opts?.index),
         activeTabId: tabId,