diff --git a/CHANGELOG.md b/CHANGELOG.md
index 523deca..7fc6594 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -75,6 +75,22 @@ version with its date and start a fresh empty `[Unreleased]` above it.
   snapshots now carry the configured context-window tier, and zeroed
   snapshots can no longer overwrite an existing reading.
 
+### Changed
+
+- The credits usage button now shows a static "Usage" tooltip through
+  Obsidian's native tooltip (aria-label), matching the other nav-row
+  buttons, instead of a browser title tooltip with the live percentage.
+
+### Fixed
+
+- Settings changed on Obsidian 1.13+ (language, auto-scroll, and the
+  other simple toggles) now persist across restarts: the declarative
+  control writes were only mirrored into the plugin data file, not the
+  `.qoderian/qoderian-settings.json` store Qoderian loads at startup.
+  Changing the language also re-localizes open chat views immediately
+  (nav tooltips and tab titles) instead of keeping the old language
+  until the view is reopened.
+
 ## [1.0.4] - 2026-08-12
 
 ### Fixed
diff --git a/src/features/chat/chat-view.ts b/src/features/chat/chat-view.ts
index 968f267..c1a4309 100644
--- a/src/features/chat/chat-view.ts
+++ b/src/features/chat/chat-view.ts
@@ -11,6 +11,7 @@ import {
   scheduleAnimationFrame,
   type ScheduledAnimationFrame,
 } from '../../shared/dom/animation-frame';
+import { setButtonTooltip } from '../../shared/dom/tooltip';
 import { createIconSvg, QODER_ICON,QODERIAN_ICON_ID } from '../../shared/icons';
 import type { HistoryConversationStatus } from './controllers/conversation-controller';
 import {
@@ -44,6 +45,8 @@ export class QoderianView extends ItemView {
   private viewContainerEl: HTMLElement | null = null;
   private logoEl: HTMLElement | null = null;
   private newTabButtonEl: HTMLElement | null = null;
+  private newConversationButtonEl: HTMLElement | null = null;
+  private historyButtonEl: HTMLElement | null = null;
 
   // Header elements
   private historyDropdown: HTMLElement | null = null;
@@ -244,14 +247,15 @@ export class QoderianView extends ItemView {
 
     this.newTabButtonEl = navActionsEl.createDiv({ cls: 'qoderian-input-nav-btn qoderian-new-tab-btn' });
     setIcon(this.newTabButtonEl, 'square-plus');
-    this.newTabButtonEl.setAttribute('aria-label', 'New tab');
+    setButtonTooltip(this.newTabButtonEl, t('commands.newTab'));
     this.newTabButtonEl.addEventListener('click', () => {
       void this.createNewTab().catch(() => new Notice('Failed to create tab'));
     });
 
     const newBtn = navActionsEl.createDiv({ cls: 'qoderian-input-nav-btn' });
     setIcon(newBtn, 'square-pen');
-    newBtn.setAttribute('aria-label', 'New conversation');
+    setButtonTooltip(newBtn, t('nav.newConversation'));
+    this.newConversationButtonEl = newBtn;
     newBtn.addEventListener('click', () => {
       void (async () => {
         await this.tabManager?.createNewConversation();
@@ -263,7 +267,8 @@ export class QoderianView extends ItemView {
     const historyContainer = navActionsEl.createDiv({ cls: 'qoderian-history-container' });
     const historyBtn = historyContainer.createDiv({ cls: 'qoderian-input-nav-btn' });
     setIcon(historyBtn, 'history');
-    historyBtn.setAttribute('aria-label', 'Chat history');
+    setButtonTooltip(historyBtn, t('nav.chatHistory'));
+    this.historyButtonEl = historyBtn;
 
     this.historyDropdown = historyContainer.createDiv({ cls: 'qoderian-history-menu' });
 
@@ -346,6 +351,17 @@ export class QoderianView extends ItemView {
     this.updateTabBarVisibility();
   }
 
+  /** Re-applies locale-dependent static text after a language change. */
+  refreshLocalizedChrome(): void {
+    if (this.newTabButtonEl) setButtonTooltip(this.newTabButtonEl, t('commands.newTab'));
+    if (this.newConversationButtonEl) {
+      setButtonTooltip(this.newConversationButtonEl, t('nav.newConversation'));
+    }
+    if (this.historyButtonEl) setButtonTooltip(this.historyButtonEl, t('nav.chatHistory'));
+    this.creditsUsageButton?.refreshLocale();
+    this.updateTabBar();
+  }
+
   // ============================================
   // Tab Management
   // ============================================
diff --git a/src/features/chat/tabs/tab-bar.ts b/src/features/chat/tabs/tab-bar.ts
index 7876c64..40a2c55 100644
--- a/src/features/chat/tabs/tab-bar.ts
+++ b/src/features/chat/tabs/tab-bar.ts
@@ -1,4 +1,5 @@
 import { scheduleAnimationFrame } from '../../../shared/dom/animation-frame';
+import { setButtonTooltip } from '../../../shared/dom/tooltip';
 import type { TabBarItem, TabId } from './types';
 
 const EXPANDED_TITLE_MAX_LENGTH = 32;
@@ -82,7 +83,7 @@ export class TabBar {
     });
 
     // Obsidian uses aria-label for hover tooltips here; adding title causes duplicate tooltip text.
-    badgeEl.setAttribute('aria-label', item.title);
+    setButtonTooltip(badgeEl, item.title);
     badgeEl.setAttribute('data-title-expanded', isTitleExpanded ? 'true' : 'false');
 
     // Click handler to switch tab
diff --git a/src/features/chat/tabs/tab-lifecycle.ts b/src/features/chat/tabs/tab-lifecycle.ts
index 3e9477b..eb443ab 100644
--- a/src/features/chat/tabs/tab-lifecycle.ts
+++ b/src/features/chat/tabs/tab-lifecycle.ts
@@ -1,3 +1,4 @@
+import { t } from '../../../i18n/i18n';
 import type QoderianPlugin from '../../../main';
 import { cleanupThinkingBlock } from '../rendering/thinking-block-renderer';
 import type { TabData } from './types';
@@ -71,5 +72,5 @@ export function getTabTitle(tab: TabData, plugin: QoderianPlugin): string {
     const conversation = plugin.getConversationSync(tab.conversationId);
     if (conversation?.title) return conversation.title;
   }
-  return 'New Chat';
+  return t('nav.newChat');
 }
diff --git a/src/features/chat/ui/credits-usage-button.ts b/src/features/chat/ui/credits-usage-button.ts
index 14e1398..7dc334e 100644
--- a/src/features/chat/ui/credits-usage-button.ts
+++ b/src/features/chat/ui/credits-usage-button.ts
@@ -7,6 +7,7 @@ import type {
 } from '../../../core/types/services';
 import { getLocale, t } from '../../../i18n/i18n';
 import { getQoderAccountUsageUrl } from '../../../qoder/config/cli-edition';
+import { setButtonTooltip } from '../../../shared/dom/tooltip';
 import { ClickPopover } from './toolbar/click-popover';
 
 /** Usage snapshots older than this are refreshed when the panel opens. */
@@ -97,6 +98,12 @@ export class CreditsUsageButton {
     this.container.remove();
   }
 
+  /** Re-applies locale-dependent text after a language change. */
+  refreshLocale(): void {
+    this.updateButton();
+    this.renderPanel();
+  }
+
   /** Fetches a fresh snapshot; cached snapshots within the TTL are kept. */
   async refresh(force: boolean): Promise<void> {
     if (this.loading) return;
@@ -125,12 +132,9 @@ export class CreditsUsageButton {
   };
 
   private updateButton(): void {
-    const percent = this.snapshot?.totalUsagePercentage;
-    if (typeof percent === 'number') {
-      this.buttonEl.setAttribute('title', t('credits.trigger', { percent: Math.round(percent) }));
-    } else {
-      this.buttonEl.setAttribute('title', t('credits.unavailable'));
-    }
+    // Same tooltip path as the other nav-row buttons (aria-label + 300ms
+    // delay); only the click behavior (popover) differs.
+    setButtonTooltip(this.buttonEl, t('credits.trigger'));
   }
 
   private renderPanel(): void {
diff --git a/src/features/settings/settings-tab.ts b/src/features/settings/settings-tab.ts
index 096c6f5..6ba12d5 100644
--- a/src/features/settings/settings-tab.ts
+++ b/src/features/settings/settings-tab.ts
@@ -417,15 +417,30 @@ export class QoderianSettingTab extends PluginSettingTab {
         return this.plugin.saveSettings();
       }
 
-      if (key === 'mediaFolder') {
-        return super.setControlValue(key, String(value).trim());
-      }
+      return this.persistControlValue(key, value);
+    }
+    // Unreachable: Obsidian < 1.13 never calls setControlValue.
+  }
 
-      const result = super.setControlValue(key, value);
+  /**
+   * The declarative base class persists into the plugin data file, but
+   * Qoderian keeps its settings in .qoderian/qoderian-settings.json, so per
+   * the API contract ("override to write to a different data source") we
+   * mutate the settings bag ourselves and save once through the store that
+   * loadSettings() actually reads — no duplicate write to data.json.
+   */
+  private async persistControlValue(key: string, value: unknown): Promise<void> {
+    // Only reached from setControlValue on Obsidian 1.13+; re-checked here so
+    // the 1.13-only view-refresh calls stay behind an explicit version guard.
+    if (requireApiVersion('1.13.0')) {
+      const settings = this.plugin.settings as unknown as Record<string, unknown>;
+      settings[key] = key === 'mediaFolder' ? String(value).trim() : value;
+      await this.plugin.saveSettings();
 
       if (key === 'locale') {
         setLocale(this.plugin.settings.locale as Locale);
         this.update();
+        this.refreshViewChrome();
       } else if (key === 'maxTabs') {
         for (const view of this.plugin.getAllViews()) {
           view.refreshTabControls();
@@ -435,10 +450,14 @@ export class QoderianSettingTab extends PluginSettingTab {
       } else if (PROMPT_SETTING_KEYS.has(key)) {
         this.schedulePromptRestart();
       }
+    }
+  }
 
-      return result;
+  /** Re-applies locale-dependent text in open chat views after a language change. */
+  private refreshViewChrome(): void {
+    for (const view of this.plugin.getAllViews()) {
+      view.refreshLocalizedChrome();
     }
-    // Unreachable: Obsidian < 1.13 never calls setControlValue.
   }
 
   /**
@@ -518,6 +537,7 @@ export class QoderianSettingTab extends PluginSettingTab {
             this.plugin.settings.locale = locale;
             await this.plugin.saveSettings();
             this.display();
+            this.refreshViewChrome();
           });
       });
 
diff --git a/src/i18n/locales/de.json b/src/i18n/locales/de.json
index 128c14f..dda8c80 100644
--- a/src/i18n/locales/de.json
+++ b/src/i18n/locales/de.json
@@ -38,6 +38,11 @@
     "newSession": "Neue Sitzung (im aktuellen Tab)",
     "closeCurrentTab": "Aktuellen Tab schließen"
   },
+  "nav": {
+    "newConversation": "Neue Unterhaltung",
+    "chatHistory": "Chatverlauf",
+    "newChat": "Neuer Chat"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "Zu diesem Punkt zurückspulen? Dateiänderungen nach dieser Nachricht werden rückgängig gemacht. Das Zurückspulen betrifft keine manuell oder über Bash bearbeiteten Dateien.",
@@ -292,7 +297,7 @@
     "renewsOn": "Verlängert am {date}",
     "usedPercent": "{percent}% verwendet",
     "left": "{count} übrig",
-    "trigger": "Nutzung - {percent}%",
+    "trigger": "Nutzung",
     "unavailable": "Nutzung nicht verfügbar"
   },
   "model": {
diff --git a/src/i18n/locales/en.json b/src/i18n/locales/en.json
index 1646cc4..a753846 100644
--- a/src/i18n/locales/en.json
+++ b/src/i18n/locales/en.json
@@ -38,6 +38,11 @@
     "newSession": "New session (in current tab)",
     "closeCurrentTab": "Close current tab"
   },
+  "nav": {
+    "newConversation": "New conversation",
+    "chatHistory": "Chat history",
+    "newChat": "New Chat"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "Rewind to this point? File changes after this message will be reverted. Rewinding does not affect files edited manually or via bash.",
@@ -292,7 +297,7 @@
     "renewsOn": "Renews on {date}",
     "usedPercent": "{percent}% used",
     "left": "{count} left",
-    "trigger": "Usage - {percent}%",
+    "trigger": "Usage",
     "unavailable": "Usage unavailable"
   },
   "model": {
diff --git a/src/i18n/locales/es.json b/src/i18n/locales/es.json
index 07d9e6c..4a91e5f 100644
--- a/src/i18n/locales/es.json
+++ b/src/i18n/locales/es.json
@@ -38,6 +38,11 @@
     "newSession": "Nueva sesión (en la pestaña actual)",
     "closeCurrentTab": "Cerrar pestaña actual"
   },
+  "nav": {
+    "newConversation": "Nueva conversación",
+    "chatHistory": "Historial del chat",
+    "newChat": "Nuevo chat"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "¿Rebobinar a este punto? Los cambios de archivos después de este mensaje serán revertidos. El rebobinado no afecta archivos editados manualmente o mediante bash.",
@@ -292,7 +297,7 @@
     "renewsOn": "Se renueva el {date}",
     "usedPercent": "{percent}% usado",
     "left": "{count} restantes",
-    "trigger": "Uso - {percent}%",
+    "trigger": "Uso",
     "unavailable": "Uso no disponible"
   },
   "model": {
diff --git a/src/i18n/locales/fr.json b/src/i18n/locales/fr.json
index 77ac30a..7b48beb 100644
--- a/src/i18n/locales/fr.json
+++ b/src/i18n/locales/fr.json
@@ -38,6 +38,11 @@
     "newSession": "Nouvelle session (dans l'onglet actuel)",
     "closeCurrentTab": "Fermer l'onglet actuel"
   },
+  "nav": {
+    "newConversation": "Nouvelle conversation",
+    "chatHistory": "Historique du chat",
+    "newChat": "Nouveau chat"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "Rembobiner jusqu'à ce point ? Les modifications de fichiers après ce message seront annulées. Le rembobinage n'affecte pas les fichiers modifiés manuellement ou via bash.",
@@ -292,7 +297,7 @@
     "renewsOn": "Renouvellement le {date}",
     "usedPercent": "{percent}% utilisés",
     "left": "{count} restants",
-    "trigger": "Utilisation - {percent}%",
+    "trigger": "Utilisation",
     "unavailable": "Utilisation indisponible"
   },
   "model": {
diff --git a/src/i18n/locales/ja.json b/src/i18n/locales/ja.json
index 4d7910b..0b21cc7 100644
--- a/src/i18n/locales/ja.json
+++ b/src/i18n/locales/ja.json
@@ -38,6 +38,11 @@
     "newSession": "新しいセッション（現在のタブ）",
     "closeCurrentTab": "現在のタブを閉じる"
   },
+  "nav": {
+    "newConversation": "新しい会話",
+    "chatHistory": "チャット履歴",
+    "newChat": "新しいチャット"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "この時点に巻き戻しますか？このメッセージ以降のファイル変更が元に戻されます。手動またはbashで編集されたファイルには影響しません。",
@@ -292,7 +297,7 @@
     "renewsOn": "{date} に更新",
     "usedPercent": "{percent}% 使用済み",
     "left": "残り {count}",
-    "trigger": "利用量 - {percent}%",
+    "trigger": "利用量",
     "unavailable": "利用量情報を取得できません"
   },
   "model": {
diff --git a/src/i18n/locales/ko.json b/src/i18n/locales/ko.json
index 8271196..046862d 100644
--- a/src/i18n/locales/ko.json
+++ b/src/i18n/locales/ko.json
@@ -38,6 +38,11 @@
     "newSession": "새 세션 (현재 탭)",
     "closeCurrentTab": "현재 탭 닫기"
   },
+  "nav": {
+    "newConversation": "새 대화",
+    "chatHistory": "대화 기록",
+    "newChat": "새 채팅"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "이 시점으로 되감으시겠습니까? 이 메시지 이후의 파일 변경 사항이 되돌려집니다. 수동으로 또는 bash를 통해 편집된 파일에는 영향을 미치지 않습니다.",
@@ -292,7 +297,7 @@
     "renewsOn": "{date}에 갱신",
     "usedPercent": "{percent}% 사용",
     "left": "{count} 남음",
-    "trigger": "사용량 - {percent}%",
+    "trigger": "사용량",
     "unavailable": "사용량을 확인할 수 없음"
   },
   "model": {
diff --git a/src/i18n/locales/pt.json b/src/i18n/locales/pt.json
index be38e07..a5e1589 100644
--- a/src/i18n/locales/pt.json
+++ b/src/i18n/locales/pt.json
@@ -38,6 +38,11 @@
     "newSession": "Nova sessão (na aba atual)",
     "closeCurrentTab": "Fechar aba atual"
   },
+  "nav": {
+    "newConversation": "Nova conversa",
+    "chatHistory": "Histórico de conversas",
+    "newChat": "Novo chat"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "Retroceder até este ponto? As alterações de arquivos após esta mensagem serão revertidas. O retrocesso não afeta arquivos editados manualmente ou via bash.",
@@ -292,7 +297,7 @@
     "renewsOn": "Renova em {date}",
     "usedPercent": "{percent}% usado",
     "left": "{count} restantes",
-    "trigger": "Uso - {percent}%",
+    "trigger": "Uso",
     "unavailable": "Uso indisponível"
   },
   "model": {
diff --git a/src/i18n/locales/ru.json b/src/i18n/locales/ru.json
index 71874bc..2ccff00 100644
--- a/src/i18n/locales/ru.json
+++ b/src/i18n/locales/ru.json
@@ -38,6 +38,11 @@
     "newSession": "Новая сессия (в текущей вкладке)",
     "closeCurrentTab": "Закрыть текущую вкладку"
   },
+  "nav": {
+    "newConversation": "Новый разговор",
+    "chatHistory": "История чата",
+    "newChat": "Новый чат"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "Откатить до этой точки? Изменения файлов после этого сообщения будут отменены. Откат не затрагивает файлы, отредактированные вручную или через bash.",
@@ -292,7 +297,7 @@
     "renewsOn": "Обновление {date}",
     "usedPercent": "использовано {percent}%",
     "left": "осталось {count}",
-    "trigger": "Использование - {percent}%",
+    "trigger": "Использование",
     "unavailable": "Использование недоступно"
   },
   "model": {
diff --git a/src/i18n/locales/zh-CN.json b/src/i18n/locales/zh-CN.json
index 6c9644d..57b45a8 100644
--- a/src/i18n/locales/zh-CN.json
+++ b/src/i18n/locales/zh-CN.json
@@ -38,6 +38,11 @@
     "newSession": "新建会话（当前标签页）",
     "closeCurrentTab": "关闭当前标签页"
   },
+  "nav": {
+    "newConversation": "新建会话",
+    "chatHistory": "聊天历史",
+    "newChat": "新会话"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "回退到此处？此消息之后的文件更改将被还原。回退不会影响手动或通过 bash 编辑的文件。",
@@ -292,7 +297,7 @@
     "renewsOn": "将于 {date} 刷新",
     "usedPercent": "已使用 {percent}%",
     "left": "剩余 {count}",
-    "trigger": "用量 - {percent}%",
+    "trigger": "用量",
     "unavailable": "用量暂不可用"
   },
   "model": {
diff --git a/src/i18n/locales/zh-TW.json b/src/i18n/locales/zh-TW.json
index 7d04f1c..73517db 100644
--- a/src/i18n/locales/zh-TW.json
+++ b/src/i18n/locales/zh-TW.json
@@ -38,6 +38,11 @@
     "newSession": "新增工作階段（目前分頁）",
     "closeCurrentTab": "關閉目前分頁"
   },
+  "nav": {
+    "newConversation": "新建對話",
+    "chatHistory": "聊天歷史",
+    "newChat": "新對話"
+  },
   "chat": {
     "rewind": {
       "confirmMessage": "回退到此處？此訊息之後的檔案變更將被還原。回退不會影響手動或透過 bash 編輯的檔案。",
@@ -292,7 +297,7 @@
     "renewsOn": "將於 {date} 刷新",
     "usedPercent": "已使用 {percent}%",
     "left": "剩餘 {count}",
-    "trigger": "用量 - {percent}%",
+    "trigger": "用量",
     "unavailable": "用量暫不可用"
   },
   "model": {
diff --git a/src/i18n/types.ts b/src/i18n/types.ts
index 3c4aed1..1487f76 100644
--- a/src/i18n/types.ts
+++ b/src/i18n/types.ts
@@ -11,6 +11,11 @@ export type TranslationKey =
   | 'commands.newSession'
   | 'commands.closeCurrentTab'
 
+  // Nav row buttons and tab badges
+  | 'nav.newConversation'
+  | 'nav.chatHistory'
+  | 'nav.newChat'
+
   // Common UI elements
   | 'common.save'
   | 'common.cancel'
diff --git a/src/shared/dom/tooltip.ts b/src/shared/dom/tooltip.ts
new file mode 100644
index 0000000..1e4164f
--- /dev/null
+++ b/src/shared/dom/tooltip.ts
@@ -0,0 +1,16 @@
+import { setTooltip } from 'obsidian';
+
+/**
+ * Hover delay (ms) for icon-button tooltips.
+ * Obsidian's native aria-label tooltips use a 1000ms cold-start delay, which
+ * feels sluggish next to the 200-500ms range common in web toolbars.
+ */
+const BUTTON_TOOLTIP_DELAY = 300;
+
+/**
+ * Sets a hover tooltip on an icon button with a snappier-than-default delay.
+ * Keeps the native Obsidian tooltip rendering (placement, arrow, a11y) intact.
+ */
+export function setButtonTooltip(el: HTMLElement, text: string): void {
+  setTooltip(el, text, { delay: BUTTON_TOOLTIP_DELAY });
+}
diff --git a/tests/__mocks__/obsidian.ts b/tests/__mocks__/obsidian.ts
index e6a0974..0cf7c23 100644
--- a/tests/__mocks__/obsidian.ts
+++ b/tests/__mocks__/obsidian.ts
@@ -32,6 +32,17 @@ export class PluginSettingTab {
   }
 
   display() {}
+
+  // Mirrors the 1.13 declarative base: mutates plugin.settings in place.
+  getControlValue(key: string): unknown {
+    return (this.plugin.settings as Record<string, unknown>)[key];
+  }
+
+  setControlValue(key: string, value: unknown): void {
+    (this.plugin.settings as Record<string, unknown>)[key] = value;
+  }
+
+  update() {}
 }
 
 export class ItemView {
@@ -263,6 +274,15 @@ export const MarkdownRenderer = {
 
 export const setIcon = jest.fn();
 
+// Mirrors the real helper: writes aria-label plus any delay override that the
+// native tooltip system would read back on hover.
+export function setTooltip(el: HTMLElement, tooltip: string, options?: { delay?: number }): void {
+  el.setAttribute('aria-label', tooltip);
+  if (options?.delay !== undefined) {
+    el.setAttribute('data-tooltip-delay', String(options.delay));
+  }
+}
+
 // Tests run against the newest API surface, so version gates take the
 // modern branch by default.
 export const requireApiVersion = jest.fn(() => true);
diff --git a/tests/unit/features/chat/ui/credits-usage-button.test.ts b/tests/unit/features/chat/ui/credits-usage-button.test.ts
index b5ec70c..e983c3d 100644
--- a/tests/unit/features/chat/ui/credits-usage-button.test.ts
+++ b/tests/unit/features/chat/ui/credits-usage-button.test.ts
@@ -2,6 +2,7 @@ import { createMockEl } from '@test/helpers/mock-element';
 
 import type { CreditsUsageSnapshot } from '@/core/types/services';
 import { CreditsUsageButton } from '@/features/chat/ui/credits-usage-button';
+import { setLocale } from '@/i18n/i18n';
 import { setActiveQoderCliEdition } from '@/qoder/config/cli-edition';
 
 const SNAPSHOT: CreditsUsageSnapshot = {
@@ -27,25 +28,42 @@ function flushPromises(): Promise<void> {
 interface ButtonHarness {
   parentEl: ReturnType<typeof createMockEl>;
   fetchUsage: jest.Mock;
+  button: CreditsUsageButton;
 }
 
 function createButton(cached: CreditsUsageSnapshot | null = SNAPSHOT): ButtonHarness {
   const parentEl = createMockEl();
   const fetchUsage = jest.fn().mockResolvedValue(SNAPSHOT);
-  new CreditsUsageButton(parentEl, {
+  const button = new CreditsUsageButton(parentEl, {
     getCachedUsage: () => cached,
     fetchUsage,
     subscribeRuntimeStatus: jest.fn().mockReturnValue(() => {}),
   });
-  return { parentEl, fetchUsage };
+  return { parentEl, fetchUsage, button };
 }
 
 describe('CreditsUsageButton', () => {
-  it('shows the overall percentage as the button tooltip', () => {
+  it('shows a static usage tooltip like the other nav-row buttons', () => {
     const { parentEl } = createButton();
 
-    expect(parentEl.querySelector('.qoderian-credits-btn')?.getAttribute('title'))
-      .toBe('Usage - 100%');
+    const btn = parentEl.querySelector('.qoderian-credits-btn');
+    expect(btn?.getAttribute('aria-label')).toBe('Usage');
+    // Same shared helper as the other nav buttons: 300ms hover delay.
+    expect(btn?.getAttribute('data-tooltip-delay')).toBe('300');
+    expect(btn?.getAttribute('title')).toBeNull();
+  });
+
+  it('re-applies localized text when the locale changes', () => {
+    const { parentEl, button } = createButton();
+
+    setLocale('zh-CN');
+    try {
+      button.refreshLocale();
+      expect(parentEl.querySelector('.qoderian-credits-btn')?.getAttribute('aria-label'))
+        .toBe('用量');
+    } finally {
+      setLocale('en');
+    }
   });
 
   it('renders plan and resource package sections like the IDE usage panel', () => {
@@ -118,8 +136,8 @@ describe('CreditsUsageButton', () => {
   it('shows an unavailable state without a snapshot', () => {
     const { parentEl } = createButton(null);
 
-    expect(parentEl.querySelector('.qoderian-credits-btn')?.getAttribute('title'))
-      .toBe('Usage unavailable');
+    expect(parentEl.querySelector('.qoderian-credits-btn')?.getAttribute('aria-label'))
+      .toBe('Usage');
     expect(parentEl.querySelector('.qoderian-credits-empty')?.textContent)
       .toBe('Usage unavailable');
   });
@@ -131,8 +149,8 @@ describe('CreditsUsageButton', () => {
     await flushPromises();
 
     expect(fetchUsage).toHaveBeenCalledTimes(1);
-    expect(parentEl.querySelector('.qoderian-credits-btn')?.getAttribute('title'))
-      .toBe('Usage - 100%');
+    expect(parentEl.querySelector('.qoderian-credits-btn')?.getAttribute('aria-label'))
+      .toBe('Usage');
     expect(parentEl.querySelector('.qoderian-credits-empty')).toBeNull();
   });
 
diff --git a/tests/unit/features/settings/settings-tab.test.ts b/tests/unit/features/settings/settings-tab.test.ts
new file mode 100644
index 0000000..faebdb6
--- /dev/null
+++ b/tests/unit/features/settings/settings-tab.test.ts
@@ -0,0 +1,42 @@
+import { QoderianSettingTab } from '@/features/settings/settings-tab';
+
+function createTab() {
+  const view = {
+    refreshLocalizedChrome: jest.fn(),
+    refreshTabControls: jest.fn(),
+  };
+  const plugin = {
+    settings: {
+      locale: 'zh-CN',
+      enableAutoScroll: true,
+      excludedTags: [] as string[],
+      mediaFolder: '',
+    },
+    saveSettings: jest.fn().mockResolvedValue(undefined),
+    getAllViews: jest.fn(() => [view]),
+  };
+  const tab = new QoderianSettingTab({} as any, plugin as any);
+  return { tab, plugin, view };
+}
+
+describe('QoderianSettingTab declarative controls', () => {
+  it('persists locale changes to the Qoderian settings store', async () => {
+    const { tab, plugin, view } = createTab();
+
+    await tab.setControlValue('locale', 'en');
+
+    expect(plugin.settings.locale).toBe('en');
+    expect(plugin.saveSettings).toHaveBeenCalledTimes(1);
+    // Open views re-apply localized static text immediately.
+    expect(view.refreshLocalizedChrome).toHaveBeenCalledTimes(1);
+  });
+
+  it('persists plain declarative controls too', async () => {
+    const { tab, plugin } = createTab();
+
+    await tab.setControlValue('enableAutoScroll', false);
+
+    expect(plugin.settings.enableAutoScroll).toBe(false);
+    expect(plugin.saveSettings).toHaveBeenCalledTimes(1);
+  });
+});