diff --git a/webui/src/components/ab-bangumi-card.vue b/webui/src/components/ab-bangumi-card.vue
index eefca765..2dc6e979 100644
--- a/webui/src/components/ab-bangumi-card.vue
+++ b/webui/src/components/ab-bangumi-card.vue
@@ -200,18 +200,40 @@ const posterSrc = computed(() => resolvePosterUrl(bangumi.poster_link));
   display: block;
 }
 
-// Card glow animation when needs review - yellow
+// 待审核的黄色光晕：静态 box-shadow 放在 ::after 上，只动画 opacity（合成器线程，
+// 不触发每帧重绘）。光晕在海报外侧，所以这里取消 overflow 裁剪，由子元素继承圆角
 .card-poster--needs-review {
-  animation: card-glow 2.5s ease-in-out infinite;
+  overflow: visible;
+
+  > * {
+    border-radius: inherit;
+  }
+
+  &::after {
+    content: '';
+    position: absolute;
+    inset: 0;
+    border-radius: inherit;
+    box-shadow: 0 0 16px 4px rgba(251, 191, 36, 0.6);
+    pointer-events: none;
+    animation: card-glow 2.5s ease-in-out infinite;
+  }
+
+  @media (prefers-reduced-motion: reduce) {
+    &::after {
+      animation: none;
+      opacity: 0.5;
+    }
+  }
 }
 
 @keyframes card-glow {
   0%,
   100% {
-    box-shadow: var(--shadow-md), 0 0 0 0 rgba(251, 191, 36, 0);
+    opacity: 0;
   }
   50% {
-    box-shadow: var(--shadow-md), 0 0 16px 4px rgba(251, 191, 36, 0.6);
+    opacity: 1;
   }
 }
 
diff --git a/webui/src/components/ab-search-bar.vue b/webui/src/components/ab-search-bar.vue
index 5b9b8ecb..6b84a939 100644
--- a/webui/src/components/ab-search-bar.vue
+++ b/webui/src/components/ab-search-bar.vue
@@ -1,9 +1,13 @@
 <script lang="ts" setup>
-import AbSearchModal from './search/ab-search-modal.vue';
-
 const { showModal, provider, loading } = storeToRefs(useSearchStore());
 const { toggleModal, getProviders } = useSearchStore();
 
+// 搜索弹窗首次打开时才加载
+const { comp: SearchModal } = useLazyModal(
+  showModal,
+  () => import('./search/ab-search-modal.vue')
+);
+
 onMounted(() => {
   getProviders();
 });
@@ -18,5 +22,5 @@ onMounted(() => {
   />
 
   <!-- Search Modal -->
-  <AbSearchModal @close="toggleModal" />
+  <component :is="SearchModal" v-if="SearchModal" @close="toggleModal" />
 </template>
diff --git a/webui/src/components/layout/ab-topbar.vue b/webui/src/components/layout/ab-topbar.vue
index 7d97999e..ed0f305d 100644
--- a/webui/src/components/layout/ab-topbar.vue
+++ b/webui/src/components/layout/ab-topbar.vue
@@ -18,6 +18,10 @@ const { isMobile } = useBreakpointQuery();
 
 const showAccount = ref(false);
 const rssRule = ref(ruleTemplate);
+const { comp: AddRss, shown: addRssShown } = useLazyModal(
+  showAddRSS,
+  () => import('@/components/ab-add-rss.vue')
+);
 
 const { start, pause, shutdown, restart, resetRule } = useProgramStore();
 const { refreshPoster } = useBangumiStore();
@@ -138,7 +142,13 @@ onUnmounted(() => {
     </div>
 
     <ab-change-account v-model:show="showAccount" />
-    <ab-add-rss v-model:show="showAddRSS" v-model:rule="rssRule" />
+    <component
+      :is="AddRss"
+      v-if="AddRss"
+      v-model:rule="rssRule"
+      :show="addRssShown"
+      @update:show="showAddRSS = $event"
+    />
   </div>
 </template>
 
diff --git a/webui/src/components/search/ab-search-modal.vue b/webui/src/components/search/ab-search-modal.vue
index 24b8aeae..2865ccd7 100644
--- a/webui/src/components/search/ab-search-modal.vue
+++ b/webui/src/components/search/ab-search-modal.vue
@@ -615,12 +615,12 @@ function handleFilterClick(
 <template>
   <Teleport to="body">
     <!-- Backdrop -->
-    <transition name="overlay">
+    <transition name="overlay" appear>
       <div v-if="showModal" class="modal-backdrop" />
     </transition>
 
     <!-- Modal -->
-    <transition name="modal">
+    <transition name="modal" appear>
       <div
         v-if="showModal"
         class="modal-container"
diff --git a/webui/src/hooks/__tests__/useEventStream.test.ts b/webui/src/hooks/__tests__/useEventStream.test.ts
index 3a83ee52..c81a63c0 100644
--- a/webui/src/hooks/__tests__/useEventStream.test.ts
+++ b/webui/src/hooks/__tests__/useEventStream.test.ts
@@ -4,7 +4,7 @@
  * store) when available.
  */
 
-import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
 import { ref } from 'vue';
 import { withSetup } from './test-utils';
 
@@ -59,12 +59,31 @@ async function freshEventStream() {
 }
 
 describe('useEventStream', () => {
+  // 单例在模块级注册 visibilitychange 监听且从不卸载；逐测试移除，避免旧实例串扰
+  const visibilityHandlers: EventListener[] = [];
+  const realAddEventListener = document.addEventListener.bind(document);
+
   beforeEach(() => {
+    vi.spyOn(document, 'addEventListener').mockImplementation(
+      (type: string, handler: unknown, opts?: unknown) => {
+        if (type === 'visibilitychange') {
+          visibilityHandlers.push(handler as EventListener);
+        }
+        realAddEventListener(type, handler as EventListener, opts as never);
+      }
+    );
     isLoggedIn.value = false;
     MockEventSource.instances = [];
     vi.stubGlobal('EventSource', MockEventSource);
   });
 
+  afterEach(() => {
+    for (const h of visibilityHandlers.splice(0)) {
+      document.removeEventListener('visibilitychange', h);
+    }
+    vi.restoreAllMocks();
+  });
+
   it('should open a connection to the events stream when logged in', async () => {
     isLoggedIn.value = true;
     const useEventStream = await freshEventStream();
@@ -176,4 +195,90 @@ describe('useEventStream', () => {
 
     expect(second).toHaveBeenCalledWith(1);
   });
+
+  it('should append log_append frames and replace on a log frame', async () => {
+    isLoggedIn.value = true;
+    const useEventStream = await freshEventStream();
+    const result = withSetup(() => useEventStream());
+    const es = MockEventSource.instances.at(-1)!;
+
+    es.emit('log_append', 'a\n');
+    expect(result.logData.value).toBe('a\n');
+    es.emit('log', 'snapshot\n');
+    es.emit('log_append', 'b\n');
+    expect(result.logData.value).toBe('snapshot\nb\n');
+    es.emit('log', 'rotated\n');
+    expect(result.logData.value).toBe('rotated\n');
+  });
+
+  it('should trim the oldest lines when appended log exceeds the cap', async () => {
+    isLoggedIn.value = true;
+    const useEventStream = await freshEventStream();
+    const result = withSetup(() => useEventStream());
+    const es = MockEventSource.instances.at(-1)!;
+
+    const line = `${'x'.repeat(99)}\n`;
+    es.emit('log', line.repeat(5000));
+    es.emit('log_append', 'tail\n');
+    const text = result.logData.value!;
+    expect(text.length).toBeLessThanOrEqual(512 * 1024);
+    expect(text.endsWith('x\ntail\n')).toBe(true);
+    expect(text.startsWith(`${'x'.repeat(99)}\n`)).toBe(true);
+  });
+
+  describe('hidden tab', () => {
+    let hidden = false;
+    function setHidden(value: boolean) {
+      hidden = value;
+      document.dispatchEvent(new Event('visibilitychange'));
+    }
+
+    beforeEach(() => {
+      vi.useFakeTimers();
+      hidden = false;
+      vi.spyOn(document, 'hidden', 'get').mockImplementation(() => hidden);
+    });
+    afterEach(() => {
+      vi.useRealTimers();
+    });
+
+    it('should close the stream after 30 s hidden and reconnect on visible', async () => {
+      isLoggedIn.value = true;
+      const useEventStream = await freshEventStream();
+      const result = withSetup(() => useEventStream());
+      const es = MockEventSource.instances.at(-1)!;
+      es.onopen?.();
+      // 旧测试遗留的单例也会连接，故以当前数量为基线
+      const baseline = MockEventSource.instances.length;
+
+      setHidden(true);
+      vi.advanceTimersByTime(30_000);
+      expect(es.closed).toBe(true);
+      expect(result.connected.value).toBe(false);
+
+      // 隐藏期间不会重连
+      vi.advanceTimersByTime(60_000);
+      expect(MockEventSource.instances).toHaveLength(baseline);
+
+      setHidden(false);
+      expect(MockEventSource.instances).toHaveLength(baseline + 1);
+      expect(MockEventSource.instances.at(-1)!.closed).toBe(false);
+    });
+
+    it('should keep the stream when hidden for less than 30 s', async () => {
+      isLoggedIn.value = true;
+      const useEventStream = await freshEventStream();
+      withSetup(() => useEventStream());
+      const es = MockEventSource.instances.at(-1)!;
+      const baseline = MockEventSource.instances.length;
+
+      setHidden(true);
+      vi.advanceTimersByTime(29_000);
+      setHidden(false);
+      vi.advanceTimersByTime(60_000);
+
+      expect(es.closed).toBe(false);
+      expect(MockEventSource.instances).toHaveLength(baseline);
+    });
+  });
 });
diff --git a/webui/src/hooks/useEventStream.ts b/webui/src/hooks/useEventStream.ts
index f0329c44..4d072fb7 100644
--- a/webui/src/hooks/useEventStream.ts
+++ b/webui/src/hooks/useEventStream.ts
@@ -22,6 +22,10 @@ export interface BusEvent {
 
 const RECONNECT_BASE_DELAY_MS = 1000;
 const RECONNECT_MAX_DELAY_MS = 15000;
+/** 标签页持续隐藏超过该时长后关闭流，可见时重连（服务端重发快照） */
+const HIDDEN_CLOSE_DELAY_MS = 30000;
+/** 累积日志文本的上限，与后端 /log 的尾部读取预算一致 */
+const LOG_MAX_CHARS = 512 * 1024;
 
 /**
  * 单一 SSE 连接（api/v1/events/stream），推送 status/downloader/log 更新，
@@ -56,6 +60,9 @@ export const useEventStream = createSharedComposable(() => {
   let source: EventSource | null = null;
   let retryCount = 0;
   let retryTimer: ReturnType<typeof setTimeout> | undefined;
+  let hiddenTimer: ReturnType<typeof setTimeout> | undefined;
+  /** 因标签页长时间隐藏而主动关闭；此状态下不重连，直到页面可见 */
+  let suspended = false;
 
   function teardown() {
     source?.close();
@@ -71,7 +78,7 @@ export const useEventStream = createSharedComposable(() => {
     );
     retryCount += 1;
     retryTimer = setTimeout(() => {
-      if (isLoggedIn.value) connect();
+      if (isLoggedIn.value && !suspended) connect();
     }, delay);
   }
 
@@ -111,6 +118,17 @@ export const useEventStream = createSharedComposable(() => {
       logData.value = (e as MessageEvent).data;
     });
 
+    es.addEventListener('log_append', (e) => {
+      const text = (logData.value ?? '') + (e as MessageEvent).data;
+      if (text.length <= LOG_MAX_CHARS) {
+        logData.value = text;
+        return;
+      }
+      // 超出上限时丢弃最旧部分，并对齐到下一行起点
+      const tail = text.slice(text.length - LOG_MAX_CHARS);
+      logData.value = tail.slice(tail.indexOf('\n') + 1);
+    });
+
     es.addEventListener('update', (e) => {
       try {
         updateData.value = JSON.parse((e as MessageEvent).data);
@@ -153,10 +171,28 @@ export const useEventStream = createSharedComposable(() => {
 
   function stop() {
     clearTimeout(retryTimer);
+    clearTimeout(hiddenTimer);
+    suspended = false;
     retryCount = 0;
     teardown();
   }
 
+  function onVisibilityChange() {
+    clearTimeout(hiddenTimer);
+    if (document.hidden) {
+      hiddenTimer = setTimeout(() => {
+        suspended = true;
+        clearTimeout(retryTimer);
+        teardown();
+      }, HIDDEN_CLOSE_DELAY_MS);
+    } else if (suspended) {
+      suspended = false;
+      retryCount = 0;
+      if (isLoggedIn.value) connect();
+    }
+  }
+  document.addEventListener('visibilitychange', onVisibilityChange);
+
   // 生命周期跟随登录状态，而非某个调用方组件的挂载/卸载——这是一个跨组件
   // 共享的单例连接（createSharedComposable），不能绑定到任意一个消费者的
   // onBeforeUnmount 上。
diff --git a/webui/src/hooks/useLazyModal.ts b/webui/src/hooks/useLazyModal.ts
new file mode 100644
index 00000000..9d5f84d1
--- /dev/null
+++ b/webui/src/hooks/useLazyModal.ts
@@ -0,0 +1,28 @@
+import type { Component, Ref } from 'vue';
+
+/**
+ * 弹窗首次打开时才加载并挂载。
+ * `comp` 就绪后才渲染，`shown` 在挂载后的下一拍再置为 true，
+ * 这样 NModal 的进入过渡（appear）仍然生效。
+ */
+export function useLazyModal(
+  open: Ref<boolean>,
+  load: () => Promise<{ default: Component }>
+) {
+  const comp = shallowRef<Component>();
+  const shown = ref(false);
+
+  watch(
+    open,
+    async (val) => {
+      if (val && !comp.value) {
+        comp.value = (await load()).default;
+        await nextTick();
+      }
+      shown.value = open.value;
+    },
+    { immediate: true }
+  );
+
+  return { comp, shown };
+}
diff --git a/webui/src/hooks/useMyI18n.ts b/webui/src/hooks/useMyI18n.ts
index 00c7ea7a..9b054fd7 100644
--- a/webui/src/hooks/useMyI18n.ts
+++ b/webui/src/hooks/useMyI18n.ts
@@ -1,15 +1,9 @@
 import { createI18n } from 'vue-i18n';
 import { createSharedComposable, useLocalStorage } from '@vueuse/core';
 import enUS from '@/i18n/en.json';
-import zhCN from '@/i18n/zh-CN.json';
 import type { ApiSuccess } from '#/api';
 
-const messages = {
-  en: enUS,
-  'zh-CN': zhCN,
-};
-
-type Languages = keyof typeof messages;
+type Languages = 'en' | 'zh-CN';
 
 function normalizeLocale(locale: string): Languages {
   if (locale.startsWith('zh')) return 'zh-CN';
@@ -20,19 +14,39 @@ export const i18n = createI18n({
   legacy: false,
   locale: normalizeLocale(navigator.language),
   fallbackLocale: 'en',
-  messages,
+  // zh-CN 先放空壳以固定语言类型，真正的消息由 loadLocale 载入
+  messages: { en: enUS, 'zh-CN': {} },
 });
 
+// 默认语言（en）静态打包；其它语言首次使用时才加载
+const loaded = new Set<Languages>(['en']);
+
+export async function loadLocale(locale: Languages) {
+  if (loaded.has(locale)) return;
+  const { default: msgs } = await import('@/i18n/zh-CN.json');
+  i18n.global.setLocaleMessage(locale, msgs);
+  loaded.add(locale);
+}
+
+/** 首次渲染前预载已保存的语言，避免先闪出英文 */
+export function loadSavedLocale() {
+  return loadLocale(
+    normalizeLocale(localStorage.getItem('lang') ?? navigator.language)
+  );
+}
+
 export const useMyI18n = createSharedComposable(() => {
   const lang = useLocalStorage<Languages>(
     'lang',
     normalizeLocale(navigator.language)
   );
 
-  i18n.global.locale.value = lang.value as unknown as Languages;
+  i18n.global.locale.value = lang.value;
 
-  watch(lang, (val) => {
-    i18n.global.locale.value = val as unknown as Languages;
+  // 先加载语言包再切换，切换期间沿用旧语言
+  watch(lang, async (val) => {
+    await loadLocale(val);
+    i18n.global.locale.value = val;
   });
 
   function changeLocale() {
diff --git a/webui/src/main.ts b/webui/src/main.ts
index 97132439..9477240f 100644
--- a/webui/src/main.ts
+++ b/webui/src/main.ts
@@ -1,7 +1,7 @@
 import { createApp } from 'vue';
 import { createPinia } from 'pinia';
 import { router } from './router';
-import { i18n } from './hooks/useMyI18n';
+import { i18n, loadSavedLocale } from './hooks/useMyI18n';
 import App from './App.vue';
 
 import '@unocss/reset/tailwind-compat.css';
@@ -13,4 +13,5 @@ const app = createApp(App);
 app.use(router);
 app.use(pinia);
 app.use(i18n);
-app.mount('#app');
+// 已保存的语言包加载完再渲染，避免先闪出英文
+loadSavedLocale().then(() => app.mount('#app'));
diff --git a/webui/src/pages/index.vue b/webui/src/pages/index.vue
index a82fa75a..7678e07b 100644
--- a/webui/src/pages/index.vue
+++ b/webui/src/pages/index.vue
@@ -8,6 +8,14 @@ definePage({
 });
 
 const { editRule } = storeToRefs(useBangumiStore());
+const editRuleOpen = computed({
+  get: () => editRule.value.show,
+  set: (val) => (editRule.value.show = val),
+});
+const { comp: EditRule, shown: editRuleShown } = useLazyModal(
+  editRuleOpen,
+  () => import('@/components/ab-edit-rule.vue')
+);
 
 // 插件页面的标题取自清单（清单到达前留空，避免闪出路由名 Plugin；清单已到达
 // 或加载失败仍无匹配页面时回退为插件 id）；插件市场用翻译后的标题，其它页面沿用路由名
@@ -74,9 +82,12 @@ function onApplyRule(rule: BangumiRule) {
       </div>
     </main>
 
-    <ab-edit-rule
-      v-model:show="editRule.show"
+    <component
+      :is="EditRule"
+      v-if="EditRule"
       v-model:rule="editRule.item"
+      :show="editRuleShown"
+      @update:show="editRuleOpen = $event"
       @enable="onEnableRule"
       @archive="onArchiveRule"
       @unarchive="onUnarchiveRule"
diff --git a/webui/src/pages/index/downloader.test.ts b/webui/src/pages/index/downloader.test.ts
new file mode 100644
index 00000000..b62fbe1c
--- /dev/null
+++ b/webui/src/pages/index/downloader.test.ts
@@ -0,0 +1,158 @@
+import { flushPromises, mount } from '@vue/test-utils';
+import { createPinia, setActivePinia } from 'pinia';
+import { ref } from 'vue';
+import type { Component } from 'vue';
+import { beforeAll, beforeEach, describe, expect, it, vi } from 'vitest';
+import { useConfigStore } from '@/store/config';
+import { useDownloaderStore } from '@/store/downloader';
+import { mockConfig } from '@/test/mocks/api';
+import type { Config } from '#/config';
+import type { QbTorrentInfo } from '#/downloader';
+
+// happy-dom 没有布局：给虚拟列表一个固定视口高度，否则一行都不渲染。
+// 必须在 naive-ui（vueuc 的 ResizeObserver 单例）加载前替换
+vi.hoisted(() => {
+  class FixedResizeObserver {
+    callback: ResizeObserverCallback;
+    constructor(callback: ResizeObserverCallback) {
+      this.callback = callback;
+    }
+
+    observe(target: Element) {
+      const entry = { target, contentRect: { width: 1000, height: 600 } };
+      this.callback(
+        [entry as unknown as ResizeObserverEntry],
+        this as unknown as ResizeObserver
+      );
+    }
+
+    unobserve() {}
+    disconnect() {}
+  }
+  globalThis.ResizeObserver = FixedResizeObserver;
+});
+
+const downloaderData = ref<QbTorrentInfo[] | null>(null);
+
+vi.mock('@/hooks/useEventStream', () => ({
+  useEventStream: () => ({ connected: ref(true), downloaderData }),
+}));
+
+vi.mock('@/utils/axios', () => ({
+  axios: { get: vi.fn(), post: vi.fn() },
+}));
+
+vi.mock('@/api/downloader', () => ({
+  apiDownloader: {
+    getTorrents: vi.fn().mockResolvedValue([]),
+    instances: vi.fn().mockResolvedValue({ default: '', instances: [] }),
+  },
+}));
+
+vi.mock('@/hooks/useMyI18n', () => ({
+  useMyI18n: () => ({
+    t: (key: string) => key,
+    returnUserLangMsg: () => '',
+  }),
+}));
+
+vi.mock('@/hooks/useMessage', () => ({
+  useMessage: () => ({ success: vi.fn(), error: vi.fn() }),
+}));
+
+function torrent(
+  hash: string,
+  savePath: string,
+  progress = 0.5
+): QbTorrentInfo {
+  return {
+    hash,
+    name: `torrent-${hash}`,
+    size: 1024,
+    progress,
+    dlspeed: 0,
+    upspeed: 0,
+    num_seeds: 0,
+    num_leechs: 0,
+    state: 'downloading',
+    eta: 0,
+    category: 'Bangumi',
+    save_path: savePath,
+    added_on: 0,
+    downloader_id: 'default',
+  };
+}
+
+describe('Downloader page', () => {
+  let DownloaderPage: Component;
+
+  beforeAll(async () => {
+    vi.stubGlobal('definePage', vi.fn());
+    // vitest 的自动导入不含 @vueuse/core
+    vi.stubGlobal('useIntervalFn', () => ({ pause: vi.fn(), resume: vi.fn() }));
+    DownloaderPage = (await import('./downloader.vue')).default;
+  });
+
+  beforeEach(() => {
+    setActivePinia(createPinia());
+    useConfigStore().config = mockConfig as unknown as Config;
+    downloaderData.value = null;
+  });
+
+  async function mountPage() {
+    const wrapper = mount(DownloaderPage, {
+      attachTo: document.body,
+      global: { stubs: { 'ab-button': true, RouterLink: true } },
+    });
+    // 首帧在挂载后到达，与真实 SSE 一致（store 的 watch 不是 immediate）
+    downloaderData.value = [
+      torrent('a1', '/dl/Show A'),
+      torrent('a2', '/dl/Show A'),
+      torrent('b1', '/dl/Show B'),
+    ];
+    await flushPromises();
+    return wrapper;
+  }
+
+  function rowOf(wrapper: Awaited<ReturnType<typeof mountPage>>, text: string) {
+    const row = wrapper
+      .findAll('.n-data-table-tbody .n-data-table-tr')
+      .find((r) => r.text().includes(text));
+    if (!row) throw new Error(`row not found: ${text}`);
+    return row;
+  }
+
+  it('should update the row when the store receives a new SSE payload', async () => {
+    const wrapper = await mountPage();
+    expect(rowOf(wrapper, 'torrent-a1').text()).toContain('50%');
+
+    downloaderData.value = [torrent('a1', '/dl/Show A', 1)];
+    await flushPromises();
+
+    expect(rowOf(wrapper, 'torrent-a1').text()).toContain('100%');
+  });
+
+  it('should select every torrent of the group when its header checkbox is checked', async () => {
+    const wrapper = await mountPage();
+
+    await rowOf(wrapper, 'Show A (2)').find('.n-checkbox').trigger('click');
+
+    expect([...useDownloaderStore().selectedKeys].sort()).toEqual([
+      'default:a1',
+      'default:a2',
+    ]);
+    expect(wrapper.find('.action-bar-count').text()).toContain('2');
+  });
+
+  it('should hide the group rows when the group is collapsed', async () => {
+    const wrapper = await mountPage();
+
+    await rowOf(wrapper, 'Show A (2)')
+      .find('.n-data-table-expand-trigger')
+      .trigger('click');
+
+    const text = wrapper.find('.n-data-table-tbody').text();
+    expect(text).not.toContain('torrent-a1');
+    expect(text).toContain('torrent-b1');
+  });
+});
diff --git a/webui/src/pages/index/downloader.vue b/webui/src/pages/index/downloader.vue
index 04ca376d..b4e9e200 100644
--- a/webui/src/pages/index/downloader.vue
+++ b/webui/src/pages/index/downloader.vue
@@ -1,5 +1,10 @@
 <script lang="ts" setup>
-import { type DataTableColumns, NDataTable } from 'naive-ui';
+import type { VNodeChild } from 'vue';
+import {
+  type DataTableColumns,
+  type DataTableRowKey,
+  NDataTable,
+} from 'naive-ui';
 import AbProgress from '@/components/basic/ab-progress.vue';
 import AbTag from '@/components/basic/ab-tag.vue';
 import { useConfirm } from '@/hooks/useConfirm';
@@ -20,8 +25,6 @@ const {
   pauseSelected,
   resumeSelected,
   deleteSelected,
-  toggleKey,
-  toggleGroup,
   clearSelection,
 } = useDownloaderStore();
 const { confirm } = useConfirm();
@@ -120,30 +123,89 @@ function stateType(state: string): 'neutral' | 'success' | 'info' | 'danger' {
   return 'info';
 }
 
-function isGroupAllSelected(group: TorrentGroup): boolean {
-  return group.torrents.every((t) =>
-    selectedKeys.value.includes(torrentKey(t))
+/** 分组头行：同一个虚拟表里以树形父行显示，children 为该组的种子 */
+interface GroupRow {
+  key: string;
+  group: TorrentGroup;
+  children: QbTorrentInfo[];
+}
+type Row = QbTorrentInfo | GroupRow;
+
+function isGroupRow(row: Row): row is GroupRow {
+  return 'group' in row;
+}
+
+function rowKey(row: Row): string {
+  return isGroupRow(row) ? row.key : torrentKey(row);
+}
+
+function rowClassName(row: Row): string {
+  return isGroupRow(row) ? 'group-row' : '';
+}
+
+/** 分组头行的名称格跨满其余列，种子列的渲染只处理种子行 */
+function torrentCell(render: (row: QbTorrentInfo) => VNodeChild) {
+  return (row: Row) => (isGroupRow(row) ? null : render(row));
+}
+
+const rows = computed<GroupRow[]>(() =>
+  groups.value.map((group) => ({
+    key: `group:${group.savePath}`,
+    group,
+    children: group.torrents,
+  }))
+);
+
+// 记录折叠的分组，新出现的分组默认展开
+const collapsed = shallowRef(new Set<string>());
+const expandedKeys = computed(() =>
+  rows.value.filter((r) => !collapsed.value.has(r.key)).map((r) => r.key)
+);
+
+function onExpandedChange(keys: DataTableRowKey[]) {
+  const open = new Set(keys);
+  collapsed.value = new Set(
+    rows.value.map((r) => r.key).filter((k) => !open.has(k))
+  );
+}
+
+const checkedKeys = computed(() => [...selectedKeys.value]);
+
+// 级联勾选会带上分组头的键，只保留种子键
+function onCheckedChange(keys: DataTableRowKey[]) {
+  const groupKeys = new Set(rows.value.map((r) => r.key));
+  selectedKeys.value = new Set(
+    keys.filter((k) => !groupKeys.has(k as string)) as string[]
   );
 }
 
 // 多个下载器实例时标出每个种子所在的实例
 const downloaders = useDownloaderInstances();
 
-const tableColumnsValue = computed<DataTableColumns<QbTorrentInfo>>(() => [
+const tableColumnsValue = computed<DataTableColumns<Row>>(() => [
   {
     type: 'selection',
   },
   {
     title: t('downloader.torrent.name'),
     key: 'name',
-    ellipsis: { tooltip: true },
+    // CSS 省略号 + title：不用逐行测量宽度的 tooltip
+    ellipsis: true,
+    className: 'name-col',
     minWidth: 200,
+    colSpan: (row: Row): number =>
+      isGroupRow(row) ? tableColumnsValue.value.length - 1 : 1,
+    cellProps: (row) => ({
+      title: isGroupRow(row) ? row.group.savePath : row.name,
+    }),
+    render: (row) =>
+      isGroupRow(row) ? `${row.group.name} (${row.group.count})` : row.name,
   },
   {
     title: t('downloader.torrent.progress'),
     key: 'progress',
     width: 160,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return h(AbProgress, {
         value: row.progress * 100,
         label: `${Math.round(row.progress * 100)}%`,
@@ -152,58 +214,58 @@ const tableColumnsValue = computed<DataTableColumns<QbTorrentInfo>>(() => [
             ? 'error'
             : 'active',
       });
-    },
+    }),
   },
   {
     title: t('downloader.torrent.status'),
     key: 'state',
     width: 100,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return h(AbTag, {
         type: stateType(row.state),
         title: stateLabel(row.state),
       });
-    },
+    }),
   },
   {
     title: t('downloader.torrent.size'),
     key: 'size',
     width: 100,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return formatSize(row.size);
-    },
+    }),
   },
   {
     title: t('downloader.torrent.dlspeed'),
     key: 'dlspeed',
     width: 110,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return formatSpeed(row.dlspeed);
-    },
+    }),
   },
   {
     title: t('downloader.torrent.upspeed'),
     key: 'upspeed',
     width: 110,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return formatSpeed(row.upspeed);
-    },
+    }),
   },
   {
     title: 'ETA',
     key: 'eta',
     width: 80,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return formatEta(row.eta);
-    },
+    }),
   },
   {
     title: t('downloader.torrent.peers'),
     key: 'peers',
     width: 110,
-    render(row: QbTorrentInfo) {
+    render: torrentCell((row) => {
       return `${row.num_seeds} / ${row.num_leechs}`;
-    },
+    }),
   },
   // 放在最后并完整显示 id（触屏没有悬停提示）
   ...(downloaders.multiple.value
@@ -216,20 +278,6 @@ const tableColumnsValue = computed<DataTableColumns<QbTorrentInfo>>(() => [
       ]
     : []),
 ]);
-
-function onCheckedChange(group: TorrentGroup, keys: string[]) {
-  const groupKeys = group.torrents.map(torrentKey);
-  const otherSelected = selectedKeys.value.filter(
-    (k) => !groupKeys.includes(k)
-  );
-  selectedKeys.value = [...otherSelected, ...keys];
-}
-
-function groupCheckedKeys(group: TorrentGroup): string[] {
-  return group.torrents
-    .map(torrentKey)
-    .filter((k) => selectedKeys.value.includes(k));
-}
 </script>
 
 <template>
@@ -302,30 +350,29 @@ function groupCheckedKeys(group: TorrentGroup): string[] {
         {{ $t('downloader.empty_torrents') }}
       </div>
 
-      <div v-else class="downloader-groups">
-        <ab-fold-panel
-          v-for="group in groups"
-          :key="group.savePath"
-          :title="`${group.name} (${group.count})`"
-          :default-open="true"
-        >
-          <NDataTable
-            :columns="tableColumnsValue"
-            :data="group.torrents"
-            :row-key="torrentKey"
-            :pagination="false"
-            :bordered="false"
-            :checked-row-keys="groupCheckedKeys(group)"
-            size="small"
-            @update:checked-row-keys="(keys: any) => onCheckedChange(group, keys as string[])"
-          />
-        </ab-fold-panel>
-      </div>
+      <!-- 单个虚拟滚动表：只渲染可见行；不放进 NCollapseItem，SSE 数据才能刷新行 -->
+      <NDataTable
+        v-else
+        class="downloader-table"
+        :columns="tableColumnsValue"
+        :data="rows"
+        :row-key="rowKey"
+        :row-class-name="rowClassName"
+        :pagination="false"
+        :bordered="false"
+        :checked-row-keys="checkedKeys"
+        :expanded-row-keys="expandedKeys"
+        virtual-scroll
+        flex-height
+        size="small"
+        @update:checked-row-keys="onCheckedChange"
+        @update:expanded-row-keys="onExpandedChange"
+      />
 
       <Transition name="fade">
-        <div v-if="selectedKeys.length > 0" class="action-bar">
+        <div v-if="selectedKeys.size > 0" class="action-bar">
           <span class="action-bar-count">
-            {{ selectedKeys.length }} {{ $t('downloader.selected') }}
+            {{ selectedKeys.size }} {{ $t('downloader.selected') }}
           </span>
           <div class="action-bar-buttons">
             <ab-button variant="primary" size="sm" @click="resumeSelected">
@@ -354,6 +401,7 @@ function groupCheckedKeys(group: TorrentGroup): string[] {
 .page-downloader {
   overflow: auto;
   flex-grow: 1;
+  min-height: 0;
   display: flex;
   flex-direction: column;
 }
@@ -362,14 +410,28 @@ function groupCheckedKeys(group: TorrentGroup): string[] {
   display: flex;
   flex-direction: column;
   flex: 1;
+  min-height: 0;
   gap: 12px;
   padding-bottom: 60px;
 }
 
-.downloader-groups {
-  display: flex;
-  flex-direction: column;
-  gap: 12px;
+// flex-height：表格填满页面剩余高度，虚拟滚动在表体内进行
+.downloader-table {
+  flex: 1;
+  min-height: 0;
+
+  :deep(.group-row .n-data-table-td) {
+    font-weight: 600;
+  }
+
+  // 树形缩进与展开按钮占 40px，名称不换行到下一行
+  :deep(.name-col) {
+    white-space: nowrap;
+  }
+
+  :deep(.name-col .n-data-table-td__ellipsis) {
+    max-width: calc(100% - 40px);
+  }
 }
 
 .downloader-empty {
diff --git a/webui/src/store/__tests__/downloader.test.ts b/webui/src/store/__tests__/downloader.test.ts
index c2a20800..c048312d 100644
--- a/webui/src/store/__tests__/downloader.test.ts
+++ b/webui/src/store/__tests__/downloader.test.ts
@@ -59,7 +59,7 @@ describe('downloader store', () => {
       torrent('a2', 'default'),
       torrent('a3', 'default'),
     ];
-    store.selectedKeys = store.torrents.slice(0, 3).map(torrentKey);
+    store.selectedKeys = new Set(store.torrents.slice(0, 3).map(torrentKey));
 
     await store.pauseSelected();
     await store.deleteSelected(true);
@@ -77,7 +77,7 @@ describe('downloader store', () => {
   it('should act only on the selected instance when the same hash is in two instances', async () => {
     const store = useDownloaderStore();
     store.torrents = [torrent('h', 'home'), torrent('h', 'seedbox')];
-    store.selectedKeys = [torrentKey(store.torrents[1])];
+    store.selectedKeys = new Set([torrentKey(store.torrents[1])]);
 
     await store.pauseSelected();
 
@@ -98,7 +98,7 @@ describe('downloader store', () => {
     async (_, failure) => {
       const store = useDownloaderStore();
       store.torrents = [torrent('a', 'home'), torrent('b', 'seedbox')];
-      store.selectedKeys = store.torrents.map(torrentKey);
+      store.selectedKeys = new Set(store.torrents.map(torrentKey));
       vi.mocked(apiDownloader.deleteTorrents).mockImplementationOnce(failure);
 
       await expect(store.deleteSelected(false)).rejects.toBeTruthy();
@@ -113,7 +113,7 @@ describe('downloader store', () => {
   it('should show the failure message when an instance returns status false', async () => {
     const store = useDownloaderStore();
     store.torrents = [torrent('a', 'home')];
-    store.selectedKeys = store.torrents.map(torrentKey);
+    store.selectedKeys = new Set(store.torrents.map(torrentKey));
     vi.mocked(apiDownloader.deleteTorrents).mockResolvedValueOnce({
       status: false,
       msg_en: 'Failed to delete torrents',
diff --git a/webui/src/store/downloader.ts b/webui/src/store/downloader.ts
index 8d15b5b9..bfe8cc3b 100644
--- a/webui/src/store/downloader.ts
+++ b/webui/src/store/downloader.ts
@@ -14,7 +14,8 @@ export function hasConfiguredDownloader(instances: PluginInstance[]): boolean {
 
 export const useDownloaderStore = defineStore('downloader', () => {
   const torrents = shallowRef<QbTorrentInfo[]>([]);
-  const selectedKeys = ref<string[]>([]);
+  // Set 而不是响应式数组：成员判断 O(1)，整体替换触发更新
+  const selectedKeys = shallowRef(new Set<string>());
   const loading = ref(false);
 
   const { downloaderData } = useEventStream();
@@ -82,7 +83,7 @@ export const useDownloaderStore = defineStore('downloader', () => {
   const opts = {
     showMessage: true,
     onSuccess() {
-      selectedKeys.value = [];
+      selectedKeys.value = new Set();
     },
     onFinally: getAll,
   };
@@ -97,7 +98,7 @@ export const useDownloaderStore = defineStore('downloader', () => {
   ) {
     const byInstance = new Map<string, string[]>();
     for (const t of torrents.value) {
-      if (!selectedKeys.value.includes(torrentKey(t))) continue;
+      if (!selectedKeys.value.has(torrentKey(t))) continue;
       const hashes = byInstance.get(t.downloader_id) ?? [];
       hashes.push(t.hash);
       byInstance.set(t.downloader_id, hashes);
@@ -134,30 +135,8 @@ export const useDownloaderStore = defineStore('downloader', () => {
     opts
   );
 
-  function toggleKey(key: string) {
-    const idx = selectedKeys.value.indexOf(key);
-    if (idx === -1) {
-      selectedKeys.value.push(key);
-    } else {
-      selectedKeys.value.splice(idx, 1);
-    }
-  }
-
-  function toggleGroup(group: TorrentGroup) {
-    const groupKeys = group.torrents.map(torrentKey);
-    const allSelected = groupKeys.every((k) => selectedKeys.value.includes(k));
-    if (allSelected) {
-      selectedKeys.value = selectedKeys.value.filter(
-        (k) => !groupKeys.includes(k)
-      );
-    } else {
-      const toAdd = groupKeys.filter((k) => !selectedKeys.value.includes(k));
-      selectedKeys.value.push(...toAdd);
-    }
-  }
-
   function clearSelection() {
-    selectedKeys.value = [];
+    selectedKeys.value = new Set();
   }
 
   return {
@@ -170,8 +149,6 @@ export const useDownloaderStore = defineStore('downloader', () => {
     pauseSelected,
     resumeSelected,
     deleteSelected,
-    toggleKey,
-    toggleGroup,
     clearSelection,
   };
 });
diff --git a/webui/types/dts/auto-imports.d.ts b/webui/types/dts/auto-imports.d.ts
index ecb80503..c323dc3c 100644
--- a/webui/types/dts/auto-imports.d.ts
+++ b/webui/types/dts/auto-imports.d.ts
@@ -67,6 +67,8 @@ declare global {
   const isRef: typeof import('vue').isRef
   const isShallow: typeof import('vue').isShallow
   const isValidNexusPhpCategoryIds: typeof import('../../src/utils/nexusphp').isValidNexusPhpCategoryIds
+  const loadLocale: typeof import('../../src/hooks/useMyI18n').loadLocale
+  const loadSavedLocale: typeof import('../../src/hooks/useMyI18n').loadSavedLocale
   const localizeFields: typeof import('../../src/utils/plugin-text').localizeFields
   const mapActions: typeof import('pinia').mapActions
   const mapGetters: typeof import('pinia').mapGetters
@@ -150,6 +152,7 @@ declare global {
   const useI18n: typeof import('vue-i18n').useI18n
   const useId: typeof import('vue').useId
   const useIntervalFn: typeof import('@vueuse/core').useIntervalFn
+  const useLazyModal: typeof import('../../src/hooks/useLazyModal').useLazyModal
   const useLocalStorage: typeof import('@vueuse/core').useLocalStorage
   const useLogStore: typeof import('../../src/store/log').useLogStore
   const useMessage: typeof import('../../src/hooks/useMessage').useMessage
diff --git a/webui/vite.config.ts b/webui/vite.config.ts
index 67e1ca63..ff1d6478 100644
--- a/webui/vite.config.ts
+++ b/webui/vite.config.ts
@@ -46,6 +46,7 @@ export default defineConfig({
     }),
     VueI18nPlugin({
       include: resolve(import.meta.dirname, './src/i18n/**'),
+      dropMessageCompiler: true,
     }),
   ],
   css: {
@@ -61,7 +62,13 @@ export default defineConfig({
       output: { minify: { compress: { dropConsole: true } } },
     },
   },
-  resolve: { tsconfigPaths: true },
+  resolve: {
+    tsconfigPaths: true,
+    // 只用运行时：模板都在构建期编译，不需要打包 @vue/compiler-*
+    alias: [
+      { find: /^vue$/, replacement: 'vue/dist/vue.runtime.esm-bundler.js' },
+    ],
+  },
   preview: { headers },
   server: {
     proxy: {