diff --git a/ui/src/components/layout/AppShell.vue b/ui/src/components/layout/AppShell.vue
index 4f1a796..d1e55fc 100644
--- a/ui/src/components/layout/AppShell.vue
+++ b/ui/src/components/layout/AppShell.vue
@@ -15,6 +15,7 @@ import TopBar from './TopBar.vue';
 import StatusBar from './StatusBar.vue';
 import Drawer from './Drawer.vue';
 import SessionPanel from '../session/SessionPanel.vue';
+import ExtensionsPane from '../session/ExtensionsPane.vue';
 import SettingsPanel from '../settings/SettingsPanel.vue';
 import ChatPanel from '../chat/ChatPanel.vue';
 import BenchPanel from '../bench/BenchPanel.vue';
@@ -116,6 +117,7 @@ function onResize() {
 const sideOpen = ref(false);
 const benchOpen = ref(false);
 const settingsOpen = ref(false);
+const extensionsOpen = ref(false);
 // 移动端工作台全屏覆盖层（FR-RESP-004）
 const benchOverlayOpen = ref(false);
 
@@ -227,11 +229,13 @@ function overlaySelectTab(tab) {
       @menu="openSide"
       @bench="openBench"
       @close-bench="closeAllBench"
+      @goto-extensions="extensionsOpen = true"
+      @goto-settings="settingsOpen = true"
     />
 
     <!-- 左栏（≥1024px 固定；<1024px 抽屉形态） -->
     <div v-if="!drawersMode" class="aside-host">
-      <SessionPanel @goto-settings="settingsOpen = true" />
+      <SessionPanel />
     </div>
 
     <!-- 左折叠把手（FR-SHELL-004；仅桌面档显示） -->
@@ -287,7 +291,7 @@ function overlaySelectTab(tab) {
     <!-- <1024px 抽屉：左 = 会话抽屉，右 = 工作台抽屉 -->
     <template v-if="drawersMode">
       <Drawer :open="sideOpen" side="left" width="260px" title="会话列表" @close="closeSide">
-        <SessionPanel @goto-settings="settingsOpen = true" />
+        <SessionPanel />
       </Drawer>
       <Drawer :open="benchOpen" side="right" width="300px" title="工作台" @close="closeBench">
         <BenchPanel />
@@ -297,6 +301,9 @@ function overlaySelectTab(tab) {
     <!-- 设置：中央模态框（SettingsPanel 自带 Teleport 遮罩 + 高斯模糊，全档位可用） -->
     <SettingsPanel :open="settingsOpen" @close="settingsOpen = false" />
 
+    <!-- 扩展管理（2026-09-15 自侧栏迁移至右上角;中央模态,与 SessionPanel 内同款组件） -->
+    <ExtensionsPane :open="extensionsOpen" @close="extensionsOpen = false" />
+
     <!-- <768px 全屏工作台覆盖层（FR-RESP-004：顶部 tab 条 + 关闭按钮） -->
     <Teleport to="body">
       <div v-if="benchOverlayOpen && tier === 'mobile'" class="bench-overlay">
diff --git a/ui/src/components/layout/TopBar.vue b/ui/src/components/layout/TopBar.vue
index 9cf762c..bbffc03 100644
--- a/ui/src/components/layout/TopBar.vue
+++ b/ui/src/components/layout/TopBar.vue
@@ -10,7 +10,8 @@
        bench.currentSources → 来源数组（工作台按钮角标数） -->
 <script setup>
 import { computed, onMounted, ref } from 'vue';
-import { APP_NAME, STATUS_LABEL } from '../../i18n/labels.js';
+import { APP_NAME, STATUS_LABEL, T } from '../../i18n/labels.js';
+import { BF } from '../../i18n/bioflow.js';
 import { useThemeStore } from '../../stores/theme.js';
 
 const props = defineProps({
@@ -28,7 +29,7 @@ const props = defineProps({
   benchOverlayOpen: { type: Boolean, default: false },
 });
 
-const emit = defineEmits(['menu', 'bench', 'close-bench']);
+const emit = defineEmits(['menu', 'bench', 'close-bench', 'goto-extensions', 'goto-settings']);
 
 /* ---------- 主题 ---------- */
 const themeStore = useThemeStore();
@@ -143,6 +144,9 @@ const iconMoon = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" str
 const iconMenu = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"><path d="M3 12h18M3 6h18M3 18h18"/></svg>';
 const iconBench = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"><path d="M6 5h12M6 12h12M6 19h12"/></svg>';
 const iconClose = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"><path d="M18 6L6 18M6 6l12 12"/></svg>';
+// 右上角快捷按钮图标(2026-09-15:会话/扩展/知识图谱/设置 自侧栏迁移)
+const iconRailExt = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M12 2l2.4 4.9 5.4.8-3.9 3.8.9 5.4-4.8-2.5-4.8 2.5.9-5.4L4.2 7.7l5.4-.8z"/><path d="M20 14v5a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2v-5"/></svg>';
+const iconRailSettings = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"><circle cx="12" cy="12" r="3"/><path d="M19.4 15a1.7 1.7 0 0 0 .34 1.87l.06.06a2 2 0 1 1-2.83 2.83l-.06-.06a1.7 1.7 0 0 0-1.87-.34 1.7 1.7 0 0 0-1 1.55V21a2 2 0 1 1-4 0v-.09a1.7 1.7 0 0 0-1-1.55 1.7 1.7 0 0 0-1.87.34l-.06.06a2 2 0 1 1-2.83-2.83l.06-.06a1.7 1.7 0 0 0 .34-1.87 1.7 1.7 0 0 0-1.55-1H3a2 2 0 1 1 0-4h.09a1.7 1.7 0 0 0 1.55-1 1.7 1.7 0 0 0-.34-1.87l-.06-.06a2 2 0 1 1 2.83-2.83l.06.06a1.7 1.7 0 0 0 1.87.34h0a1.7 1.7 0 0 0 1-1.55V3a2 2 0 1 1 4 0v.09a1.7 1.7 0 0 0 1 1.55h0a1.7 1.7 0 0 0 1.87-.34l.06-.06a2 2 0 1 1 2.83 2.83l-.06.06a1.7 1.7 0 0 0-.34 1.87v0a1.7 1.7 0 0 0 1.55 1H21a2 2 0 1 1 0 4h-.09a1.7 1.7 0 0 0-1.55 1z"/></svg>';
 </script>
 
 <template>
@@ -193,6 +197,18 @@ const iconClose = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" st
       <span v-if="!benchOverlayOpen && sourceCount != null" class="bench-btn-count">{{ sourceCount }}</span>
     </button>
 
+    <!-- 右上角快捷按钮(2026-09-15 自侧栏迁移;仅 desktop/laptop;三按钮同行右对齐) -->
+    <template v-if="tier === 'desktop' || tier === 'laptop'">
+      <button class="icon-btn top-rail-btn" type="button" :title="BF.extRailTitle" :aria-label="BF.extRailTitle"
+              @click="$emit('goto-extensions')">
+        <span v-html="iconRailExt"></span>
+      </button>
+      <button class="icon-btn top-rail-btn" type="button" :title="T.railSettings" :aria-label="T.railSettings"
+              @click="$emit('goto-settings')">
+        <span v-html="iconRailSettings"></span>
+      </button>
+    </template>
+
     <!-- 主题切换（日月 SVG + rotate 180° 400ms，FR-THEME-002） -->
     <button
       class="icon-btn"
diff --git a/ui/src/components/session/SessionPanel.vue b/ui/src/components/session/SessionPanel.vue
index d326dfe..a628af7 100644
--- a/ui/src/components/session/SessionPanel.vue
+++ b/ui/src/components/session/SessionPanel.vue
@@ -3,24 +3,17 @@
 // 新建按钮 / 搜索框 / 分组列表（今天/昨天/更早）/ 状态点四态 / 活动渐变条 /
 // 重命名双击 / 删除二次确认 / 空搜索提示（FR-SESSION-001~009）。
 // 注意：左抽屉形态由 B1 布局层负责；本组件只渲染面板内容（session-panel 根元素）。
-import { computed, onMounted, ref } from 'vue';
+import { computed, onMounted } from 'vue';
 import { useSessionsStore } from '../../stores/sessions.js';
 import { useChatStore } from '../../stores/chat.js';
 import { T, SESSION_GROUPS } from '../../i18n/labels.js';
 import SearchBox from './SearchBox.vue';
 import SessionItem from './SessionItem.vue';
-import SessionRail from './SessionRail.vue';
-// 用户自定义扩展分析：侧栏「扩展」入口（仅列表/历史/删除；创建在对话引导卡）
-import ExtensionsPane from './ExtensionsPane.vue';
-
-const emit = defineEmits(['open-rail', 'goto-kg', 'goto-settings']);
 
 const sessions = useSessionsStore();
 const chat = useChatStore();
 
 const confirmDelete = computed(() => sessions._confirmDelete || null);
-const extensionsOpen = ref(false);
-
 onMounted(() => {
   sessions.load().catch(() => {
     /* 列表加载失败 → error 状态展示空态/离线态（失败必须可见，PRD §2.2） */
@@ -146,17 +139,6 @@ const doDelete = async () => {
 
     </div>
 
-    <!-- 折叠后的图标轨（FR-SHELL-004 的 B2 侧内容） -->
-    <SessionRail
-      :active="true"
-      @open="$emit('open-rail')"
-      @goto-extensions="extensionsOpen = true"
-      @goto-kg="$emit('goto-kg')"
-      @goto-settings="$emit('goto-settings')"
-    />
-
-    <!-- 用户自定义扩展分析侧栏管理（仅列表/历史/删除） -->
-    <ExtensionsPane :open="extensionsOpen" @close="extensionsOpen = false" />
 
     <!-- 删除二次确认（FR-SESSION-007）
          Teleport 到 body：SessionPanel 在平板档渲染于 B1 的 Drawer 内，
diff --git a/ui/src/components/session/SessionRail.vue b/ui/src/components/session/SessionRail.vue
deleted file mode 100644
index 774c2b0..0000000
--- a/ui/src/components/session/SessionRail.vue
+++ /dev/null
@@ -1,89 +0,0 @@
-<script setup>
-// session/SessionRail.vue —— 左栏折叠后的 64px 图标轨（FR-SHELL-004 的 B2 侧）
-// 会话/扩展/图谱/设置四个 rail-item；会话项当前，带左侧渐变竖条。
-// 「扩展」入口 = 用户自定义扩展分析侧栏管理（仅列表/历史/删除，创建在对话引导卡）。
-import { BF } from '../../i18n/bioflow.js';
-import { T } from '../../i18n/labels.js';
-
-defineProps({
-  active: { type: Boolean, default: true },
-});
-
-const emit = defineEmits(['open', 'goto-extensions', 'goto-kg', 'goto-settings']);
-</script>
-
-<template>
-  <div class="collapsed-rail">
-    <button class="rail-item" :class="{ active }" :title="T.railSession" type="button" @click="emit('open')">
-      <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round">
-        <path d="M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z" />
-      </svg>
-    </button>
-    <button class="rail-item" :title="BF.extRailTitle" type="button" @click="emit('goto-extensions')">
-      <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-        <path d="M12 2l2.4 4.9 5.4.8-3.9 3.8.9 5.4-4.8-2.5-4.8 2.5.9-5.4L4.2 7.7l5.4-.8z" />
-        <path d="M20 14v5a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2v-5" />
-      </svg>
-    </button>
-    <button class="rail-item" :title="T.railKg" type="button" @click="emit('goto-kg')">
-      <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round">
-        <path d="M4 19.5A2.5 2.5 0 0 1 6.5 17H20" />
-        <path d="M6.5 2H20v20H6.5A2.5 2.5 0 0 1 4 19.5v-15A2.5 2.5 0 0 1 6.5 2z" />
-      </svg>
-    </button>
-    <button class="rail-item" :title="T.railSettings" type="button" @click="emit('goto-settings')">
-      <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round">
-        <circle cx="12" cy="12" r="3" />
-        <path d="M19.4 15a1.7 1.7 0 0 0 .34 1.87l.06.06a2 2 0 1 1-2.83 2.83l-.06-.06a1.7 1.7 0 0 0-1.87-.34 1.7 1.7 0 0 0-1 1.55V21a2 2 0 1 1-4 0v-.09a1.7 1.7 0 0 0-1-1.55 1.7 1.7 0 0 0-1.87.34l-.06.06a2 2 0 1 1-2.83-2.83l.06-.06a1.7 1.7 0 0 0 .34-1.87 1.7 1.7 0 0 0-1.55-1H3a2 2 0 1 1 0-4h.09a1.7 1.7 0 0 0 1.55-1 1.7 1.7 0 0 0-.34-1.87l-.06-.06a2 2 0 1 1 2.83-2.83l.06.06a1.7 1.7 0 0 0 1.87.34h0a1.7 1.7 0 0 0 1-1.55V3a2 2 0 1 1 4 0v.09a1.7 1.7 0 0 0 1 1.55h0a1.7 1.7 0 0 0 1.87-.34l.06-.06a2 2 0 1 1 2.83 2.83l-.06.06a1.7 1.7 0 0 0-.34 1.87v0a1.7 1.7 0 0 0 1.55 1H21a2 2 0 1 1 0 4h-.09a1.7 1.7 0 0 0-1.55 1z" />
-      </svg>
-    </button>
-  </div>
-</template>
-
-<style scoped>
-/* 兜底样式（类名按 UI_SPEC §3 / §7） */
-.collapsed-rail {
-  display: flex;
-  flex-direction: row;          /* 展开态：三个图标横向一排 */
-  align-items: center;
-  justify-content: center;      /* 展开态：横向居中 */
-  gap: 14px;
-  width: 100%;
-  padding: 0 14px 14px;
-  margin-top: auto;             /* 居底：与折叠态同一元素，切换时 Y 高度不变 */
-}
-.rail-item {
-  display: inline-flex;
-  align-items: center;
-  justify-content: center;
-  width: 34px;
-  height: 34px;
-  border-radius: var(--pa-r-md);
-  color: var(--pa-ink-muted);
-  position: relative;
-  transition: background 0.2s var(--pa-ease), color 0.2s var(--pa-ease);
-  cursor: pointer;
-}
-.rail-item:hover {
-  background: var(--pa-surface-2);
-  color: var(--pa-ink);
-}
-.rail-item svg {
-  width: 17px;
-  height: 17px;
-}
-.rail-item.active {
-  color: var(--pa-ink);
-  background: var(--pa-surface-2);
-}
-.rail-item.active::before {
-  content: '';
-  position: absolute;
-  left: -8px;
-  top: 8px;
-  bottom: 8px;
-  width: 2px;
-  background: var(--pa-gradient);
-  border-radius: 2px;
-}
-</style>
diff --git a/ui/src/styles/animations.css b/ui/src/styles/animations.css
index a5f5d2a..8ee8d48 100644
--- a/ui/src/styles/animations.css
+++ b/ui/src/styles/animations.css
@@ -61,8 +61,13 @@
 
 /* 主题图标切换 rotate 180°（400ms）——挂在 .theme-toggle-anim 上 */
 .theme-toggle-anim {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
   transition: transform .4s var(--pa-ease);
 }
+/* svg 脱离行内基线,避免主题图标较其他按钮图标下沉(2026-09-15 对齐修复) */
+.theme-toggle-anim svg { display: block; }
 .theme-toggle-anim.flipped { transform: rotate(180deg); }
 
 /* 面板折叠 .3s ease-out：app-shell 的 grid-template-columns 过渡在 base.css .app-shell 上声明 */
diff --git a/ui/src/styles/base.css b/ui/src/styles/base.css
index ac2eaff..5ae0937 100644
--- a/ui/src/styles/base.css
+++ b/ui/src/styles/base.css
@@ -119,6 +119,8 @@ html.drawer-open { overflow: hidden; }
 }
 .icon-btn svg { width: 16px; height: 16px; }
 .icon-btn:disabled { opacity: .45; cursor: not-allowed; }
+.top-rail-btn { margin-left: 2px; }
+.top-rail-btn > span { display: flex; align-items: center; justify-content: center; }
 
 /* 状态徽章（pill，三编码：颜色+图标+文字，UI_SPEC §4.1 / PRD §2.1） */
 .badge {
@@ -175,23 +177,6 @@ html.drawer-open { overflow: hidden; }
 }
 .session-panel .inner { display: flex; flex-direction: column; min-height: 0; width: 260px; flex: 1; transition: opacity .2s var(--pa-ease); }
 .side-collapsed .session-panel .inner { opacity: 0; pointer-events: none; }
-.side-collapsed .session-panel .collapsed-rail {
-  flex-direction: column; /* 折叠态：64px 窄轨纵向排布 */
-  align-items: center;    /* 折叠态：轨内居中，图标原样 */
-  padding: 0 0 14px;      /* 折叠态：去掉展开态的水平 14px（底 14px 两态一致） */
-}
-.rail-item {
-  display: inline-flex; align-items: center; justify-content: center;
-  width: 34px; height: 34px; border-radius: var(--pa-r-md);
-  color: var(--pa-ink-muted); position: relative;
-  transition: background .2s var(--pa-ease), color .2s var(--pa-ease);
-}
-.rail-item svg { width: 17px; height: 17px; }
-.rail-item.active { color: var(--pa-ink); background: var(--pa-surface-2); }
-.rail-item.active::before {
-  content: ""; position: absolute; left: -8px; top: 8px; bottom: 8px; width: 2px;
-  background: var(--pa-gradient); border-radius: 2px;
-}
 
 .session-panel .pad { padding: 14px 14px 10px; display: flex; flex-direction: column; gap: 10px; }
 .new-task-btn {
@@ -798,7 +783,6 @@ html.drawer-open { overflow: hidden; }
    ============================================================ */
 @media (hover: hover) {
   .icon-btn:hover:not(:disabled) { color: var(--pa-ink); background: var(--pa-surface-2); }
-  .rail-item:hover { background: var(--pa-surface-2); color: var(--pa-ink); }
   .new-task-btn:hover {
     box-shadow: 0 0 24px rgba(0,212,255, calc(.4 * var(--pa-glow-opacity)));
     transform: translateY(-1px);
@@ -833,7 +817,6 @@ html.drawer-open { overflow: hidden; }
   .msg.assistant::before { background: var(--pa-gradient); }
   .ft-dl { opacity: 1; }
   .session-item:active { background: var(--pa-surface-2); }
-  .rail-item:active { background: var(--pa-surface-2); color: var(--pa-ink); }
   .icon-btn:active:not(:disabled) { color: var(--pa-ink); background: var(--pa-surface-2); }
   .chip:active { color: var(--pa-ink); }
   .mode-pill:active { color: var(--pa-ink); background: var(--pa-surface-2); }
diff --git a/ui/tests/r3debug/extensions.test.js b/ui/tests/r3debug/extensions.test.js
index fcc83a9..d81606c 100644
--- a/ui/tests/r3debug/extensions.test.js
+++ b/ui/tests/r3debug/extensions.test.js
@@ -3,7 +3,7 @@
 //   1) §4 事件帧 → 块映射（applyExtensionFrame 全事件集幂等/追加/终态纪律）
 //   2) sendExtension 流（用户消息落库 → 骨架 → SSE 帧分派 → 终态收口/错误标注）
 //   3) uploadExtensionFile / trialRunExtension / confirmExtensionRun store 动作
-//   4) 卡片组件 mount 冒烟（8 个扩展卡 + SessionRail 扩展入口）
+//   4) 卡片组件 mount 冒烟（8 个扩展卡）
 //   5) intent.js 创建意图词典（§5 A 层同表双跑）
 //
 // 运行方式（worktree 内）：cd ui && npx vitest run --config tests/r3debug/vitest.config.js tests/r3debug/extensions.test.js
@@ -97,7 +97,6 @@ import ExtensionPublishCard from '../../src/components/chat/ExtensionPublishCard
 import ExtensionCandidatesCard from '../../src/components/chat/ExtensionCandidatesCard.vue';
 import ExtensionConfirmCard from '../../src/components/chat/ExtensionConfirmCard.vue';
 import ExtensionRunCard from '../../src/components/chat/ExtensionRunCard.vue';
-import SessionRail from '../../src/components/session/SessionRail.vue';
 
 /** 构造一个最小 SSE Response（供 bioflowChatStream mock 返回） */
 function makeSseResponse(frames) {
@@ -631,12 +630,4 @@ describe('卡片组件 mount 冒烟', () => {
     expect(w.text()).toContain('out/x');
   });
 
-  it('SessionRail 渲染：扩展入口 emits goto-extensions', async () => {
-    const w = mount(SessionRail, { props: { active: true } });
-    const items = w.findAll('.rail-item');
-    expect(items.length).toBe(4);
-    expect(items[1].attributes('title')).toContain('扩展');
-    await items[1].trigger('click');
-    expect(w.emitted('goto-extensions')).toBeTruthy();
-  });
 });