diff --git a/frontend-web/src/components/workspace/input-box.tsx b/frontend-web/src/components/workspace/input-box.tsx
index ac6bd91c..4d0a0be8 100644
--- a/frontend-web/src/components/workspace/input-box.tsx
+++ b/frontend-web/src/components/workspace/input-box.tsx
@@ -143,6 +143,7 @@ export function InputBox({
   hideAdminRecommendedQuestions,
   compact,
   hideContextTools,
+  hideMemoryTool = true,
   ...props
 }: Omit<ComponentProps<typeof PromptInput>, "onSubmit"> & {
   assistantId?: string | null;
@@ -153,6 +154,11 @@ export function InputBox({
   /** 隐藏输入框工具条上的「写作 / 记忆 / 参考文献」上下文开关按钮（任务深链工作区等
    *  受控场景用；文件/模型等其他按钮不受影响）。 */
   hideContextTools?: boolean;
+  /**
+   * 仅控制「记忆」开关的可见性。产品当前全局隐藏，传入 false 即可无损恢复。
+   * 写作和参考文献开关不受影响。
+   */
+  hideMemoryTool?: boolean;
   disabled?: boolean;
   context: Omit<
     AgentThreadContext,
@@ -752,7 +758,7 @@ export function InputBox({
                 )}
               />
             )}
-            {!frontendRagActive && !hideContextTools && <Tooltip
+            {!frontendRagActive && !hideContextTools && !hideMemoryTool && <Tooltip
               content={
                 context.writing_mode
                   ? "写作模式已开启：报告由深度研究管线按「通用分析结构」撰写，优先使用对话中已检索的资料"
diff --git a/frontend-web/src/components/workspace/thread-title.tsx b/frontend-web/src/components/workspace/thread-title.tsx
index f6934e8f..8eb5af59 100644
--- a/frontend-web/src/components/workspace/thread-title.tsx
+++ b/frontend-web/src/components/workspace/thread-title.tsx
@@ -3,16 +3,18 @@ import { useEffect } from "react";
 
 import { useI18n } from "@/core/i18n/hooks";
 import type { AgentThreadState } from "@/core/threads";
-import { sanitizeThreadTitleForDisplay } from "@/core/threads/utils";
-import { desensitize } from "@/lib/desensitize";
+import { sanitizeThreadTitleForDisplay } from "@/core/threads/utils";
+import { desensitize } from "@/lib/desensitize";
+import { cn } from "@/lib/utils";
 
 import { useThreadChat } from "./chats";
 import { FlipDisplay } from "./flip-display";
 
-export function ThreadTitle({
-  threadId,
-  thread,
-}: {
+export function ThreadTitle({
+  className,
+  threadId,
+  thread,
+}: {
   className?: string;
   threadId: string;
   thread: BaseStream<AgentThreadState>;
@@ -47,9 +49,9 @@ export function ThreadTitle({
   if (!thread.values?.title) {
     return null;
   }
-  const visibleTitle = desensitize(displayTitle);
-  return (
-    <FlipDisplay uniqueKey={threadId} className="min-w-0 w-full">
+  const visibleTitle = desensitize(displayTitle);
+  return (
+    <FlipDisplay uniqueKey={threadId} className={cn("min-w-0 w-full", className)}>
       <span className="block truncate" title={visibleTitle}>
         {visibleTitle}
       </span>
diff --git a/frontend-web/src/core/page-layout/sidebar-menu.ts b/frontend-web/src/core/page-layout/sidebar-menu.ts
index c3a1ee68..697c3025 100644
--- a/frontend-web/src/core/page-layout/sidebar-menu.ts
+++ b/frontend-web/src/core/page-layout/sidebar-menu.ts
@@ -88,12 +88,12 @@ export const sidebarMenuItems: MenuItem[] = [
       },
       { id: "qa-zzxd", label: "XD应用", icon: Layout, path: "/page/strategy/qa/zzxd" },
       { id: "qa-research", label: "课题研究", icon: FileText, path: "/page/canvas/ai-writing" },
-      {
-        id: "qa-research-chat",
-        label: "课题研究(对话版)",
-        icon: FileText,
-        path: "/page/canvas/ai-writing-chat",
-      },
+      // {
+      //   id: "qa-research-chat",
+      //   label: "课题研究(对话版)",
+      //   icon: FileText,
+      //   path: "/page/canvas/ai-writing-chat",
+      // },
       {
         id: "qa-deep-research",
         label: "深度研究",
diff --git a/frontend-web/src/pages/ChatPage.tsx b/frontend-web/src/pages/ChatPage.tsx
index 33819cf9..e516a9f2 100644
--- a/frontend-web/src/pages/ChatPage.tsx
+++ b/frontend-web/src/pages/ChatPage.tsx
@@ -38,12 +38,16 @@ import { CompactModeGuide } from "@/components/workspace/compact-mode-guide";
 import { Welcome } from "@/components/workspace/welcome";
 import { CompactWelcome } from "@/components/workspace/compact-welcome";
 import { readSidebarEnabled } from "@/core/page-layout/sidebar-enabled";
-import { isChatsIframeWorkspacePath } from "@/core/page-layout/chats-iframe-route";
+import {
+  buildFullChatNavigationPath,
+  isChatsIframeWorkspacePath,
+} from "@/core/page-layout/chats-iframe-route";
 import { isEmbedActive, isHideChromeActive } from "@/core/embed/embed-session";
 import { isWujieEnv } from "@/core/embed/wujie";
 import { useSidebar } from "@/components/ui/sidebar";
 import { Button } from "@/components/ui/button";
-import { PanelLeftOpen } from "lucide-react";
+import { MessageSquarePlus, PanelLeftOpen } from "lucide-react";
+import { useNavigate } from "react-router-dom";
 import { useAgentSelector, useAgentsPaginated } from "@/core/agents";
 import { useI18n } from "@/core/i18n/hooks";
 import { useModels } from "@/core/models/hooks";
@@ -114,6 +118,7 @@ function clearBrowserContextParamsFromHash() {
 export default function ChatPage() {
   const routeBase = useRouteBase();
   const router = useRouter();
+  const navigate = useNavigate();
   const searchParams = useSearchParams();
   const pathname = usePathname();
   // `chatMode=full` is used by an embedded standard chat. It intentionally
@@ -671,6 +676,20 @@ export default function ChatPage() {
     chromeByPreference && !isChatsIframeWorkspacePath(pathname);
   const compactLanding = isLandingState && compactChrome;
   const compactActionsHidden = isHideChromeActive();
+  const headerNewChatPath = useMemo(
+    () =>
+      buildFullChatNavigationPath(
+        `${routeBase}/chats/new`,
+        searchParams.toString(),
+      ),
+    [routeBase, searchParams],
+  );
+  const handleHeaderNewChat = useCallback(() => {
+    navigate(headerNewChatPath, {
+      replace: true,
+      state: { resetAt: Date.now() },
+    });
+  }, [headerNewChatPath, navigate]);
   // 简洁模式新手引导：仅面向「无全局导航栏/侧边栏」的正常简洁布局。iframe 嵌入
   // （embed=1）、去 chrome（hideChrome=1）、强制收起侧栏（无界部署）等环境同样没有
   // 全局 chrome，但不该在外部系统里弹引导。
@@ -709,27 +728,43 @@ export default function ChatPage() {
             )}
           >
             <div className="flex min-w-0 flex-1 items-center overflow-hidden text-sm font-medium">
-              <ThreadTitle threadId={threadId} thread={displayThread} />
-            </div>
-            <div className="flex shrink-0 items-center gap-2">
-              {/* 仅在收起态显示「展开历史」钮；展开后由侧栏内（新对话右侧）的收起钮负责收起。 */}
+              {/* 左栏收起后，展开入口固定在聊天区左上角。 */}
               {compactChrome && !historySidebarOpen && !compactActionsHidden && (
                 <Button
                   type="button"
                   variant="ghost"
                   size="icon-sm"
                   onClick={toggleHistorySidebar}
-                  title="打开历史记录"
-                  aria-label="打开历史记录"
-                  className="text-muted-foreground hover:text-foreground"
+                  title="展开左侧栏"
+                  aria-label="展开左侧栏"
+                  className="mr-1 shrink-0 text-muted-foreground hover:text-foreground"
                 >
                   <PanelLeftOpen className="size-4" />
                 </Button>
               )}
+              <ThreadTitle
+                className="-translate-y-1"
+                threadId={threadId}
+                thread={displayThread}
+              />
+            </div>
+            <div className="flex shrink-0 items-center gap-2">
               <TokenUsageIndicator
                 enabled={tokenUsageEnabled}
                 messages={displayThread.messages}
               />
+              {compactChrome && !historySidebarOpen && !compactActionsHidden && (
+                <Button
+                  type="button"
+                  variant="ghost"
+                  size="sm"
+                  onClick={handleHeaderNewChat}
+                  className="text-muted-foreground hover:text-foreground"
+                >
+                  <MessageSquarePlus className="size-4" />
+                  新建对话
+                </Button>
+              )}
               <ExportTrigger threadId={threadId} />
               <KnowledgeSaveTrigger threadId={threadId} />
               <ArtifactTrigger />
@@ -797,11 +832,10 @@ export default function ChatPage() {
                   isLandingState &&
                     !compactLanding &&
                     "-translate-y-[calc(50vh-96px)]",
-                  compactLanding
-                    ? "max-w-[calc(var(--container-width-xl)+150px)]"
-                    : isLandingState
-                      ? "max-w-[calc(var(--container-width-md)+150px)]"
-                      : "max-w-(--container-width-lg)",
+                  // 新对话落地态在全量与简洁模式使用同一输入框宽度。
+                  isLandingState
+                    ? "max-w-[calc(var(--container-width-md)+150px)]"
+                    : "max-w-(--container-width-lg)",
                 )}
               >
                 <div className="absolute -top-4 right-0 left-0 z-0">
diff --git a/frontend-web/src/pages/iframe-chat-mode-buttons.test.ts b/frontend-web/src/pages/iframe-chat-mode-buttons.test.ts
index e9144784..562f277d 100644
--- a/frontend-web/src/pages/iframe-chat-mode-buttons.test.ts
+++ b/frontend-web/src/pages/iframe-chat-mode-buttons.test.ts
@@ -4,7 +4,7 @@ import test from "node:test";
 // @ts-ignore Node's test runner resolves the local .ts module directly.
 import { buildIframeModeButtons } from "./iframe-chat-mode-buttons.ts";
 
-test("includes the context compression toggle in the iframe chat toolbar", () => {
+test("hides the memory toggle while retaining the other iframe chat toolbar controls", () => {
   const buttons = buildIframeModeButtons({
     agentSelected: false,
     writingModeEnabled: false,
@@ -20,7 +20,6 @@ test("includes the context compression toggle in the iframe chat toolbar", () =>
     buttons.map((button) => button.key),
     [
       "writing",
-      "memory",
       "references",
       "contextCompression",
       "pro",
@@ -29,6 +28,22 @@ test("includes the context compression toggle in the iframe chat toolbar", () =>
   );
 });
 
+test("can restore the iframe memory toggle when the feature is re-enabled", () => {
+  const buttons = buildIframeModeButtons({
+    agentSelected: false,
+    writingModeEnabled: false,
+    memoryInjectionEnabled: true,
+    hideMemoryButton: false,
+    referenceModeEntryEnabled: true,
+    ragModeEnabled: false,
+    ragModeLocked: false,
+    contextCompressionEnabled: false,
+    proModeEnabled: false,
+  });
+
+  assert.equal(buttons.some((button) => button.key === "memory"), true);
+});
+
 test("hides the references toggle when reference mode is disabled globally", () => {
   const buttons = buildIframeModeButtons({
     agentSelected: false,
diff --git a/frontend-web/src/pages/iframe-chat-mode-buttons.ts b/frontend-web/src/pages/iframe-chat-mode-buttons.ts
index 506fde9f..814726a2 100644
--- a/frontend-web/src/pages/iframe-chat-mode-buttons.ts
+++ b/frontend-web/src/pages/iframe-chat-mode-buttons.ts
@@ -15,6 +15,8 @@ type BuildIframeModeButtonsInput = {
   agentSelected: boolean;
   writingModeEnabled: boolean;
   memoryInjectionEnabled: boolean;
+  /** 产品当前全局隐藏记忆入口；保留 false 供后续无损恢复。 */
+  hideMemoryButton?: boolean;
   referenceModeEntryEnabled: boolean;
   ragModeEnabled: boolean;
   ragModeLocked: boolean;
@@ -26,6 +28,7 @@ export function buildIframeModeButtons({
   agentSelected,
   writingModeEnabled,
   memoryInjectionEnabled,
+  hideMemoryButton = true,
   referenceModeEntryEnabled,
   ragModeEnabled,
   ragModeLocked,
@@ -65,7 +68,9 @@ export function buildIframeModeButtons({
       active: agentSelected,
     },
   ];
-  return referenceModeEntryEnabled
-    ? buttons
-    : buttons.filter((button) => button.key !== "references");
+  return buttons.filter(
+    (button) =>
+      (referenceModeEntryEnabled || button.key !== "references") &&
+      (!hideMemoryButton || button.key !== "memory"),
+  );
 }