diff --git a/CHANGELOG.md b/CHANGELOG.md
index f4fbc438..240a15ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,12 @@
 
 ## [Unreleased]
 
+## [v0.51.471] — 2026-06-17 — Release QF (searchable settings)
+
+### Added
+
+- **Settings is now searchable (#3850).** A search box at the top of the Settings panel lets you find any setting across all sections (Appearance, Preferences, Providers, Plugins, System) without clicking through tabs — type a label fragment (e.g. "model", "theme", "language") and matching fields appear in a dropdown with their section breadcrumb. Clicking a result jumps to that section, scrolls the field into view, and pulses a brief highlight on it. Search clears after a pick. The index is built once on first search (covering lazily-loaded provider/plugin cards) and memoized. Thanks @rodboev.
+
 ## [v0.51.470] — 2026-06-17 — Release QE (transcript virtualization now experimental / off by default)
 
 ### Changed
diff --git a/static/i18n.js b/static/i18n.js
index 49f048a1..3033b323 100644
--- a/static/i18n.js
+++ b/static/i18n.js
@@ -614,6 +614,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: 'Settings',
+    settings_search_placeholder: 'Search settings…',
+    settings_search_no_results: 'No settings found.',
     settings_save_btn: 'Save Settings',
     settings_label_model: 'Default Model',
     settings_desc_model: 'Used for new conversations. Existing conversations keep their selected model.',
@@ -2102,6 +2104,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: 'Impostazioni',
+    settings_search_placeholder: 'Ricerca impostazioni…',
+    settings_search_no_results: 'Nessuna impostazione trovata.',
     settings_save_btn: 'Salva Impostazioni',
     settings_label_model: 'Modello Predefinito',
     settings_desc_model: 'Usato per le nuove conversazioni. Le conversazioni esistenti mantengono il modello selezionato.',
@@ -3581,6 +3585,8 @@ const LOCALES = {
     settings_help_issue_desc: 'GitHub で既存のレポートを検索するか、新しく報告を作成します。',
     settings_help_issue_link: 'GitHub Issues を開く',
     settings_title: '設定',
+    settings_search_placeholder: '設定を検索…',
+    settings_search_no_results: '設定が見つかりません。',
     settings_save_btn: '設定を保存',
     settings_label_model: 'デフォルトモデル',
     settings_desc_model: '新しい会話で使用されます。既存の会話は選択済みモデルを保持します。',
@@ -4852,6 +4858,8 @@ const LOCALES = {
     all_uploads_failed: (n) => `Не удалось загрузить все ${n} файлов`,
     archive_extracted: (n, c) => `Извлечено ${n} файл(ов) из ${c} архив(ов)`,
     settings_title: 'Настройки',
+    settings_search_placeholder: 'Поиск параметров…',
+    settings_search_no_results: 'Параметры не найдены.',
     settings_save_btn: 'Сохранить настройки',
     settings_label_model: 'Модель по умолчанию',
     settings_desc_model: 'Используется для новых бесед. Существующие беседы сохраняют выбранную модель.',
@@ -6248,6 +6256,8 @@ const LOCALES = {
     archive_extracted: (n, c) => `${n} archivo(s) extraído(s) de ${c} archivo(s) comprimido(s)`,
     // settings panel
     settings_title: 'Configuración',
+    settings_search_placeholder: 'Buscar configuración…',
+    settings_search_no_results: 'No se encontraron configuraciones.',
     settings_save_btn: 'Guardar configuración',
     settings_label_model: 'Modelo predeterminado',
     settings_desc_model: 'Se usa para conversaciones nuevas. Las conversaciones existentes conservan su modelo seleccionado.',
@@ -7642,6 +7652,8 @@ const LOCALES = {
     all_uploads_failed: (n) => `Alle ${n} Upload(s) fehlgeschlagen`,
     // settings panel
     settings_title: 'Einstellungen',
+    settings_search_placeholder: 'Einstellungen durchsuchen…',
+    settings_search_no_results: 'Keine Einstellungen gefunden.',
     settings_save_btn: 'Einstellungen speichern',
     settings_label_model: 'Standard-Modell',
     settings_desc_model: 'Wird für neue Chats verwendet. Bestehende Chats behalten ihr ausgewähltes Modell.',
@@ -9101,6 +9113,8 @@ const LOCALES = {
     all_uploads_failed: (n) => `${n} 个文件全部上传失败`,
     // settings panel
     settings_title: '设置',
+    settings_search_placeholder: '搜索设置…',
+    settings_search_no_results: '未找到设置。',
     settings_save_btn: '保存设置',
     settings_label_model: '默认模型',
     settings_desc_model: '用于新对话。现有对话保持各自选定的模型。',
@@ -10725,6 +10739,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: '設定',
+    settings_search_placeholder: '搜尋設定…',
+    settings_search_no_results: '找不到設定。',
     settings_save_btn: '儲存設定',
     settings_label_model: '預設模型',
     settings_desc_model: '用於新對話。現有對話會保留各自選定的模型。',
@@ -12096,6 +12112,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: 'Configurações',
+    settings_search_placeholder: 'Pesquisar configurações…',
+    settings_search_no_results: 'Nenhuma configuração encontrada.',
     settings_save_btn: 'Salvar Configurações',
     settings_label_model: 'Modelo Padrão',
     settings_desc_model: 'Usado para novas conversas. Conversas existentes mantêm o modelo selecionado.',
@@ -13476,6 +13494,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: '설정',
+    settings_search_placeholder: '설정 검색…',
+    settings_search_no_results: '설정을 찾을 수 없습니다.',
     settings_save_btn: '설정 저장',
     settings_label_model: '기본 모델',
     settings_desc_model: '새 대화에 사용됩니다. 기존 대화는 선택된 모델을 유지합니다.',
@@ -14873,6 +14893,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: 'Paramètres',
+    settings_search_placeholder: 'Rechercher les paramètres…',
+    settings_search_no_results: 'Aucun paramètre trouvé.',
     settings_save_btn: 'Enregistrer les paramètres',
     settings_label_model: 'Modèle par défaut',
     settings_desc_model: 'Utilisé pour les nouvelles conversations. Les conversations existantes conservent leur modèle sélectionné.',
@@ -16371,6 +16393,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Search existing reports or open a new one on GitHub.',
     settings_help_issue_link: 'Open GitHub Issues',
     settings_title: 'Ayarlar',
+    settings_search_placeholder: 'Ayarları ara…',
+    settings_search_no_results: 'Ayar bulunamadı.',
     settings_save_btn: 'Ayarları Kaydet',
       settings_label_model: 'Varsayılan Model',
       settings_label_auxiliary_models: 'Yardımcı Modeller',
@@ -17863,6 +17887,8 @@ const LOCALES = {
     settings_help_issue_desc: 'Przeszukaj istniejące zgłoszenia lub utwórz nowe w serwisie GitHub.',
     settings_help_issue_link: 'Otwórz zgłoszenia GitHub',
     settings_title: 'Ustawienia',
+    settings_search_placeholder: 'Szukaj ustawień…',
+    settings_search_no_results: 'Nie znaleziono ustawień.',
     settings_save_btn: 'Zapisz ustawienia',
     settings_label_model: 'Domyślny model',
     settings_desc_model: 'Używany dla nowych konwersacji. Istniejące konwersacje zachowują swój wybrany model.',
diff --git a/static/index.html b/static/index.html
index 4d9dde78..cdb42b85 100644
--- a/static/index.html
+++ b/static/index.html
@@ -348,6 +348,16 @@
         <span data-i18n="tab_settings">Settings</span>
       </div>
       <div class="side-menu" id="settingsMenu">
+        <div class="settings-search sidebar-search">
+          <svg class="sidebar-search-icon" viewBox="0 0 24 24" fill="none" stroke="currentColor"
+            stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true">
+            <circle cx="11" cy="11" r="8"/>
+            <path d="M21 21l-4.35-4.35"/>
+          </svg>
+          <input id="settingsSearch" data-i18n-placeholder="settings_search_placeholder"
+            placeholder="Search settings…" oninput="filterSettings(this.value)" autocomplete="off">
+          <div id="settingsSearchResults" class="settings-search-results" style="display:none"></div>
+        </div>
         <button type="button" class="side-menu-item active" data-settings-section="conversation" onclick="switchSettingsSection('conversation')">
           <svg width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><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>
           <span data-i18n="settings_tab_conversation">Conversation</span>
diff --git a/static/panels.js b/static/panels.js
index 1c6d1c82..3338c1e1 100644
--- a/static/panels.js
+++ b/static/panels.js
@@ -154,6 +154,8 @@ function syncAppTitlebar() {
 }
 
 function _beginSettingsPanelSession() {
+  _settingsIndex = null;
+  _settingsIndexPromise = null;
   _settingsDirty = false;
   _settingsThemeOnOpen = localStorage.getItem('hermes-theme') || 'dark';
   _settingsSkinOnOpen = localStorage.getItem('hermes-skin') || 'default';
@@ -164,6 +166,18 @@ function _beginSettingsPanelSession() {
     _settingsAppearanceAutosaveTimer = null;
   }
   _settingsAppearanceAutosaveRetryPayload = null;
+  if (!_settingsSearchDismissListenerRegistered) {
+    _settingsSearchDismissListenerRegistered = true;
+    document.addEventListener('click', e => {
+      if (!e.target.closest('#settingsMenu')) {
+        const r = $('settingsSearchResults');
+        if (r) {
+          r.style.display = 'none';
+          r.innerHTML = '';
+        }
+      }
+    });
+  }
   _resetSettingsPanelState();
 }
 
@@ -5948,6 +5962,10 @@ let _settingsFontSizeOnOpen = null; // track font size at open time for discard
 let _settingsHermesDefaultModelOnOpen = '';
 let _settingsSection = 'conversation';
 let _currentSettingsSection = 'conversation';
+let _settingsIndex = null;
+let _settingsIndexPromise = null;
+let _settingsSearchSeq = 0;
+let _settingsSearchDismissListenerRegistered = false;
 let _settingsAppearanceAutosaveTimer = null;
 let _settingsAppearanceAutosaveRetryPayload = null;
 let _settingsPreferencesAutosaveTimer = null;
@@ -6136,7 +6154,7 @@ function _toggleTabVisibilityChip(panel){
   _scheduleAppearanceAutosave();
 }
 
-function switchSettingsSection(name){
+function switchSettingsSection(name,opts){
   // If the main content is not showing settings, just remember the section
   // without force-switching the panel. The section will be applied when the
   // user next opens settings via switchPanel(). (#appearance-auto-reopen)
@@ -6170,9 +6188,171 @@ function switchSettingsSection(name){
   // Sync mobile dropdown
   const dd=$('settingsSectionDropdown');
   if(dd && dd.value!==section) dd.value=section;
-  // Lazy-load integration panels when their tabs are opened
-  if(section==='providers') loadProvidersPanel();
-  if(section==='plugins') loadPluginsPanel();
+  // Lazy-load integration panels when their tabs are opened. Search
+  // navigation passes skipLazyLoad: the loaders rebuild the pane DOM from a
+  // fresh fetch, which would detach the field it is about to scroll to.
+  if(!(opts&&opts.skipLazyLoad)){
+    if(section==='providers') loadProvidersPanel();
+    if(section==='plugins') loadPluginsPanel();
+  }
+}
+
+async function _buildSettingsIndex() {
+  if (_settingsIndex) return;
+  // Memoize the in-flight build so concurrent searches share one pass; the
+  // lazy pane loaders are not guaranteed re-entrant.
+  if (_settingsIndexPromise) return _settingsIndexPromise;
+  const promise = (async () => {
+    // Ensure lazy-loaded panes are populated before reading the DOM
+    await Promise.all([loadProvidersPanel(), loadPluginsPanel()]);
+    const index = [];
+    const sectionMap = {
+      settingsPaneConversation: 'conversation',
+      settingsPaneAppearance: 'appearance',
+      settingsPanePreferences: 'preferences',
+      settingsPaneProviders: 'providers',
+      settingsPanePlugins: 'plugins',
+      settingsPaneSystem: 'system',
+      settingsPaneHelp: 'help',
+    };
+    for (const [paneId, sectionKey] of Object.entries(sectionMap)) {
+      const pane = $(paneId);
+      if (!pane) continue;
+      pane.querySelectorAll('.settings-field').forEach(field => {
+        const labelEl = field.querySelector('label[data-i18n]');
+        if (!labelEl) return;
+        const i18nKey = labelEl.dataset.i18n;
+        const label = t(i18nKey) || labelEl.textContent.trim();
+        if (label) index.push({ label, sectionKey, i18nKey, el: field });
+      });
+      if (sectionKey === 'providers') {
+        pane.querySelectorAll('.provider-card').forEach(card => {
+          const cardName = ((card.querySelector('.provider-card-name') || {}).textContent || '').trim();
+          if (cardName) index.push({ label: cardName, sectionKey, el: card, cardName });
+          card.querySelectorAll('.provider-card-field').forEach(field => {
+            const fieldLabel = ((field.querySelector('.provider-card-label') || {}).textContent || '').trim();
+            const label = [cardName, fieldLabel].filter(Boolean).join(' ');
+            if (label) index.push({ label, sectionKey, el: field, cardName, fieldLabel });
+          });
+        });
+      }
+      if (sectionKey === 'plugins') {
+        pane.querySelectorAll('.plugin-card').forEach(card => {
+          const cardName = ((card.querySelector('.provider-card-name') || {}).textContent || '').trim();
+          if (cardName) index.push({ label: cardName, sectionKey, el: card, cardName });
+        });
+      }
+    }
+    // A panel-session reset while building clears the memo; drop this result
+    // instead of resurrecting a stale index for the new session.
+    if (_settingsIndexPromise === promise) _settingsIndex = index;
+  })().catch(e => { if (_settingsIndexPromise === promise) _settingsIndexPromise = null; throw e; });
+  _settingsIndexPromise = promise;
+  return promise;
+}
+
+async function filterSettings(query) {
+  const resultsEl = $('settingsSearchResults');
+  if (!resultsEl) return;
+  const q = (query || '').trim().toLowerCase();
+  if (!q) { ++_settingsSearchSeq; resultsEl.style.display = 'none'; resultsEl.innerHTML = ''; return; }
+  const seq = ++_settingsSearchSeq;
+  await _buildSettingsIndex();
+  // A newer keystroke superseded this query while the index was building.
+  if (seq !== _settingsSearchSeq) return;
+  const sectionLabels = {
+    conversation: t('settings_tab_conversation') || 'Conversation',
+    appearance: t('settings_tab_appearance') || 'Appearance',
+    preferences: t('settings_tab_preferences') || 'Preferences',
+    providers: t('providers_tab_title') || 'Providers',
+    plugins: t('settings_tab_plugins') || 'Plugins',
+    system: t('settings_tab_system') || 'System',
+    help: t('settings_tab_help') || 'Help',
+  };
+  const matches = (_settingsIndex || []).filter(entry =>
+    entry.label.toLowerCase().includes(q)
+  );
+  if (!matches.length) {
+    resultsEl.innerHTML = `<div class="settings-search-empty">${esc(t('settings_search_no_results') || 'No settings found.')}</div>`;
+    resultsEl.style.display = '';
+    return;
+  }
+  resultsEl.innerHTML = '';
+  for (const m of matches.slice(0, 12)) {
+    const item = document.createElement('button');
+    item.type = 'button';
+    item.className = 'settings-search-result';
+    item.innerHTML = `<span class="settings-search-section">${esc(sectionLabels[m.sectionKey] || m.sectionKey)}</span>` +
+      `<span class="settings-search-arrow">›</span>` +
+      `<span class="settings-search-label">${esc(m.label)}</span>`;
+    item.addEventListener('click', () => {
+      _navigateToSettingsField(m);
+      resultsEl.style.display = 'none';
+      resultsEl.innerHTML = '';
+      const input = $('settingsSearch');
+      if (input) input.value = '';
+    });
+    resultsEl.appendChild(item);
+  }
+  resultsEl.style.display = '';
+}
+
+function _navigateToSettingsField(entry) {
+  // The panes were populated when the index was built, so skip the tab-switch
+  // lazy reload: loadProvidersPanel()/loadPluginsPanel() rebuild the pane DOM
+  // from a fresh fetch and would detach the node mid-scroll.
+  switchSettingsSection(entry.sectionKey, { skipLazyLoad: true });
+  requestAnimationFrame(() => {
+    const el = _resolveSettingsField(entry);
+    if (!el) return;
+    el.scrollIntoView({ block: 'center', behavior: 'smooth' });
+    _highlightSettingsField(el);
+  });
+}
+
+function _resolveSettingsField(entry) {
+  // Re-resolve in the live DOM: any pane re-render since indexing (e.g. the
+  // user visited the tab) replaces the node the index captured.
+  const paneIds = {
+    conversation: 'settingsPaneConversation',
+    appearance: 'settingsPaneAppearance',
+    preferences: 'settingsPanePreferences',
+    providers: 'settingsPaneProviders',
+    plugins: 'settingsPanePlugins',
+    system: 'settingsPaneSystem',
+    help: 'settingsPaneHelp',
+  };
+  const pane = $(paneIds[entry.sectionKey]);
+  if (pane && entry.cardName && (entry.sectionKey === 'providers' || entry.sectionKey === 'plugins')) {
+    const cards = entry.sectionKey === 'providers'
+      ? pane.querySelectorAll('.provider-card')
+      : pane.querySelectorAll('.plugin-card');
+    for (const card of cards) {
+      const name = ((card.querySelector('.provider-card-name') || {}).textContent || '').trim();
+      if (name !== entry.cardName) continue;
+      if (entry.fieldLabel && entry.sectionKey === 'providers') {
+        for (const field of card.querySelectorAll('.provider-card-field')) {
+          const label = ((field.querySelector('.provider-card-label') || {}).textContent || '').trim();
+          if (label === entry.fieldLabel) return field;
+        }
+      }
+      return card;
+    }
+  }
+  const labelEl = pane && entry.i18nKey
+    ? pane.querySelector(`label[data-i18n="${CSS.escape(entry.i18nKey)}"]`)
+    : null;
+  const live = labelEl && labelEl.closest('.settings-field');
+  if (live) return live;
+  return entry.el && entry.el.isConnected ? entry.el : null;
+}
+
+function _highlightSettingsField(el) {
+  if (!el) return;
+  el.classList.remove('settings-field-highlight');
+  void el.offsetWidth;
+  el.classList.add('settings-field-highlight');
+  setTimeout(() => el.classList.remove('settings-field-highlight'), 1800);
 }
 
 function _syncHermesPanelSessionActions(){
@@ -8906,8 +9086,8 @@ function loadGatewayStatus(){
 }
 // Load MCP servers when system settings tab opens
 const _origSwitchSettings=switchSettingsSection;
-switchSettingsSection=function(name){
-  _origSwitchSettings(name);
+switchSettingsSection=function(name, opts){
+  _origSwitchSettings(name, opts);
   if(name==='preferences') updateNotificationPermissionStatus();
   if(name==='system'){loadMcpServers();loadMcpTools();loadGatewayStatus();}
 };
diff --git a/static/style.css b/static/style.css
index 9c14ef3a..a322218e 100644
--- a/static/style.css
+++ b/static/style.css
@@ -5908,3 +5908,16 @@ html[data-conversation-outline="enabled"] #outlineToggleBtn:not([hidden]){displa
 @media(max-width:900px){
   #outlineToggleBtn,#outlinePanelWrapper{display:none!important;}
 }
+
+/* Settings search */
+#settingsMenu .settings-search { position: relative; }
+.settings-search-results { position: absolute; top: 100%; left: 0; right: 0; z-index: 200; background: var(--dropdown-bg, var(--bg)); border: 1px solid var(--border2); border-radius: 8px; box-shadow: 0 4px 16px rgba(0, 0, 0, 0.18); overflow: hidden; margin-top: 2px; }
+.settings-search-result { display: flex; align-items: center; gap: 4px; width: 100%; padding: 7px 12px; background: none; border: none; text-align: left; cursor: pointer; font-size: 12px; color: var(--text); transition: background 0.1s; }
+.settings-search-result:hover { background: var(--hover-bg); }
+.settings-search-section { color: var(--muted); font-size: 11px; flex-shrink: 0; }
+.settings-search-arrow { color: var(--muted); font-size: 11px; }
+.settings-search-label { color: var(--text); min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+.settings-search-empty { padding: 10px 12px; font-size: 12px; color: var(--muted); }
+/* Settings field highlight (mirrors msg-question-highlight / _highlightQuestionRow pattern) */
+.settings-field-highlight { animation: settings-field-pulse 1.6s ease-out; }
+@keyframes settings-field-pulse { 0% { box-shadow: 0 0 0 0 var(--focus-ring); } 35% { box-shadow: 0 0 0 4px var(--focus-ring); } 100% { box-shadow: 0 0 0 0 rgba(0, 0, 0, 0); } }
diff --git a/tests/test_3850_settings_search.py b/tests/test_3850_settings_search.py
new file mode 100644
index 00000000..36a57540
--- /dev/null
+++ b/tests/test_3850_settings_search.py
@@ -0,0 +1,197 @@
+"""Regression tests for searchable settings feature.
+
+The Settings panel must have a search input and filtering capability to allow
+users to find settings across all tabs without having to click through each section.
+
+Issue: #3850 (Add search input at top of Settings panel)
+"""
+from pathlib import Path
+
+INDEX_HTML = (Path(__file__).parent.parent / "static" / "index.html").read_text(encoding="utf-8")
+PANELS_JS = (Path(__file__).parent.parent / "static" / "panels.js").read_text(encoding="utf-8")
+I18N_JS = (Path(__file__).parent.parent / "static" / "i18n.js").read_text(encoding="utf-8")
+STYLE_CSS = (Path(__file__).parent.parent / "static" / "style.css").read_text(encoding="utf-8")
+
+
+class TestSettingsSearch:
+    """Search input and filtering must be present and functional."""
+
+    def test_index_html_has_search_input(self):
+        """index.html must contain the search input element with correct id."""
+        assert 'id="settingsSearch"' in INDEX_HTML, (
+            "index.html must contain a search input with id='settingsSearch'"
+        )
+        assert 'filterSettings(this.value)' in INDEX_HTML, (
+            "index.html search input must have oninput='filterSettings(this.value)'"
+        )
+        assert 'data-i18n-placeholder="settings_search_placeholder"' in INDEX_HTML, (
+            "index.html search input must have data-i18n-placeholder attribute"
+        )
+
+    def test_index_html_has_search_results_dropdown(self):
+        """index.html must contain the search results dropdown element."""
+        assert 'id="settingsSearchResults"' in INDEX_HTML, (
+            "index.html must contain a results dropdown with id='settingsSearchResults'"
+        )
+        assert 'class="settings-search-results"' in INDEX_HTML, (
+            "index.html results dropdown must have class='settings-search-results'"
+        )
+
+    def test_panels_js_has_build_settings_index_function(self):
+        """panels.js must contain _buildSettingsIndex function."""
+        assert "function _buildSettingsIndex()" in PANELS_JS, (
+            "panels.js must contain _buildSettingsIndex() function"
+        )
+        assert "settingsPaneConversation" in PANELS_JS[PANELS_JS.find("function _buildSettingsIndex()"):], (
+            "_buildSettingsIndex must reference settingsPaneConversation pane"
+        )
+
+    def test_panels_js_has_filter_settings_function(self):
+        """panels.js must contain filterSettings function."""
+        assert "function filterSettings(query)" in PANELS_JS, (
+            "panels.js must contain filterSettings(query) function"
+        )
+        assert "toLowerCase().includes(q)" in PANELS_JS, (
+            "filterSettings must do case-insensitive substring matching"
+        )
+
+    def test_panels_js_has_navigate_to_field_function(self):
+        """panels.js must contain _navigateToSettingsField function."""
+        assert "function _navigateToSettingsField(entry)" in PANELS_JS, (
+            "panels.js must contain _navigateToSettingsField(entry) function"
+        )
+        assert "switchSettingsSection" in PANELS_JS[PANELS_JS.find("function _navigateToSettingsField"):], (
+            "_navigateToSettingsField must call switchSettingsSection"
+        )
+
+    def test_panels_js_has_highlight_settings_field_function(self):
+        """panels.js must contain _highlightSettingsField function."""
+        assert "function _highlightSettingsField(el)" in PANELS_JS, (
+            "panels.js must contain _highlightSettingsField(el) function"
+        )
+        assert "settings-field-highlight" in PANELS_JS[PANELS_JS.find("function _highlightSettingsField"):], (
+            "_highlightSettingsField must toggle 'settings-field-highlight' class"
+        )
+
+    def test_panels_js_resets_index_on_panel_open(self):
+        """panels.js _beginSettingsPanelSession must reset the settings index."""
+        idx = PANELS_JS.find("function _beginSettingsPanelSession()")
+        assert idx >= 0, "_beginSettingsPanelSession function not found"
+        body = PANELS_JS[idx:idx + 300]
+        assert "_settingsIndex = null" in body, (
+            "_beginSettingsPanelSession must reset _settingsIndex to null"
+        )
+
+    def test_i18n_js_has_search_placeholder_key(self):
+        """i18n.js must contain settings_search_placeholder key."""
+        assert "settings_search_placeholder:" in I18N_JS, (
+            "i18n.js must contain settings_search_placeholder key"
+        )
+        assert "Search settings" in I18N_JS, (
+            "settings_search_placeholder must have an appropriate translation"
+        )
+
+    def test_i18n_js_has_no_results_key(self):
+        """i18n.js must contain settings_search_no_results key."""
+        assert "settings_search_no_results:" in I18N_JS, (
+            "i18n.js must contain settings_search_no_results key"
+        )
+        assert "No settings found" in I18N_JS, (
+            "settings_search_no_results must have an appropriate translation"
+        )
+
+    def test_style_css_has_search_results_style(self):
+        """style.css must contain styles for the search results dropdown."""
+        assert ".settings-search-results" in STYLE_CSS, (
+            "style.css must contain .settings-search-results class"
+        )
+        assert ".settings-search-result" in STYLE_CSS, (
+            "style.css must contain .settings-search-result class for individual items"
+        )
+
+    def test_style_css_has_field_highlight_style(self):
+        """style.css must contain styles for field highlighting."""
+        assert ".settings-field-highlight" in STYLE_CSS, (
+            "style.css must contain .settings-field-highlight class"
+        )
+        assert "settings-field-pulse" in STYLE_CSS, (
+            "style.css must contain settings-field-pulse animation"
+        )
+
+    def test_style_css_has_search_positioning(self):
+        """style.css must position search results absolutely within the menu."""
+        assert "position:relative" in STYLE_CSS and ".settings-search" in STYLE_CSS, (
+            "style.css must make .settings-search relative positioned"
+        )
+        assert "position:absolute" in STYLE_CSS and ".settings-search-results" in STYLE_CSS, (
+            "style.css must make .settings-search-results absolutely positioned"
+        )
+
+    def test_panels_js_handles_providers_pane(self):
+        """panels.js must handle the Providers pane in index building."""
+        idx = PANELS_JS.find("function _buildSettingsIndex()")
+        assert idx >= 0, "_buildSettingsIndex not found"
+        body = PANELS_JS[idx:idx + 2000]
+        assert "settingsPaneProviders" in body, (
+            "_buildSettingsIndex must handle Providers pane"
+        )
+
+    def test_panels_js_handles_plugins_pane(self):
+        """panels.js must handle the Plugins pane in index building."""
+        idx = PANELS_JS.find("function _buildSettingsIndex()")
+        assert idx >= 0, "_buildSettingsIndex not found"
+        body = PANELS_JS[idx:idx + 2000]
+        assert "settingsPanePlugins" in body, (
+            "_buildSettingsIndex must handle Plugins pane"
+        )
+
+    def test_settings_index_includes_provider_cards(self):
+        """Providers pane entries must index provider cards and API key fields."""
+        idx = PANELS_JS.find("function _buildSettingsIndex()")
+        assert idx >= 0, "_buildSettingsIndex not found"
+        body = PANELS_JS[idx:idx + 3500]
+        assert "pane.querySelectorAll('.provider-card')" in body, (
+            "_buildSettingsIndex must scan provider cards so Providers search is not empty"
+        )
+        assert "card.querySelectorAll('.provider-card-field')" in body, (
+            "_buildSettingsIndex must index provider card fields like API key controls"
+        )
+
+    def test_settings_index_includes_plugin_cards(self):
+        """Plugins pane entries must index plugin cards by plugin name."""
+        idx = PANELS_JS.find("function _buildSettingsIndex()")
+        assert idx >= 0, "_buildSettingsIndex not found"
+        body = PANELS_JS[idx:idx + 3500]
+        assert "pane.querySelectorAll('.plugin-card')" in body, (
+            "_buildSettingsIndex must scan plugin cards so Plugins search is not empty"
+        )
+
+    def test_resolve_settings_field_rehydrates_provider_plugin_cards(self):
+        """Provider and plugin search entries must survive pane re-renders."""
+        idx = PANELS_JS.find("function _resolveSettingsField(entry)")
+        assert idx >= 0, "_resolveSettingsField not found"
+        body = PANELS_JS[idx:idx + 2200]
+        assert "entry.cardName && (entry.sectionKey === 'providers' || entry.sectionKey === 'plugins')" in body, (
+            "_resolveSettingsField must re-find provider/plugin cards by name after lazy pane re-renders"
+        )
+        assert "card.querySelectorAll('.provider-card-field')" in body, (
+            "_resolveSettingsField must be able to re-find provider card fields by label"
+        )
+
+    def test_filter_settings_caps_results(self):
+        """filterSettings must cap results at 12 items."""
+        idx = PANELS_JS.find("function filterSettings(query)")
+        assert idx >= 0, "filterSettings function not found"
+        body = PANELS_JS[idx:idx + 2000]
+        assert ".slice(0, 12)" in body, (
+            "filterSettings must cap results at 12 items with .slice(0, 12)"
+        )
+
+    def test_filter_settings_uses_escaping(self):
+        """filterSettings must escape HTML in rendered text with esc()."""
+        idx = PANELS_JS.find("function filterSettings(query)")
+        assert idx >= 0, "filterSettings function not found"
+        body = PANELS_JS[idx:idx + 2000]
+        assert "esc(" in body, (
+            "filterSettings must use esc() for HTML escaping of all rendered text"
+        )