fix(defaultModel): prevent star button injection into non-model menus

src/pages/content/defaultModel/__tests__/modelLocker.test.ts

@@ -614,6 +614,90 @@ describe('DefaultModelManager (default model locker)', () => {
     expect(selectorBtn.click).toHaveBeenCalledTimes(0);
   });
 
+  it('does not inject star buttons into the settings menu (desktop-settings-menu)', async () => {
+    const { default: DefaultModelManager } = await import('../modelLocker');
+    await DefaultModelManager.getInstance().init();
+    destroyManager = () => DefaultModelManager.getInstance().destroy();
+
+    // Simulate the Gemini settings/profile dropdown (has class desktop-settings-menu)
+    const settingsMenu = document.createElement('div');
+    settingsMenu.className = 'mat-mdc-menu-panel collapsed desktop-settings-menu ia-redesign';
+    settingsMenu.setAttribute('role', 'menu');
+
+    const settingsItem = document.createElement('a');
+    settingsItem.setAttribute('role', 'menuitem');
+    settingsItem.innerHTML = `
+      <span class="mat-mdc-menu-item-text">
+        <div class="menu-entry-with-badge">
+          <span class="gds-label-l">个人使用场景</span>
+        </div>
+      </span>
+    `;
+    settingsMenu.appendChild(settingsItem);
+
+    const themeItem = document.createElement('button');
+    themeItem.setAttribute('role', 'menuitem');
+    themeItem.innerHTML = `
+      <span class="mat-mdc-menu-item-text">
+        <span class="gds-label-l">主题</span>
+      </span>
+    `;
+    settingsMenu.appendChild(themeItem);
+
+    document.body.appendChild(settingsMenu);
+
+    await Promise.resolve();
+    await vi.advanceTimersByTimeAsync(500);
+
+    // Star buttons should NOT be injected into settings menu items
+    expect(settingsItem.querySelector('.gv-default-star-btn')).toBeNull();
+    expect(themeItem.querySelector('.gv-default-star-btn')).toBeNull();
+  });
+
+  it('does not inject star buttons into the theme submenu (menuitemradio without model markers)', async () => {
+    const { default: DefaultModelManager } = await import('../modelLocker');
+    await DefaultModelManager.getInstance().init();
+    destroyManager = () => DefaultModelManager.getInstance().destroy();
+
+    // Simulate the Gemini theme picker submenu (has menuitemradio but no model markers)
+    const themeMenu = document.createElement('div');
+    themeMenu.className = 'mat-mdc-menu-panel';
+    themeMenu.setAttribute('role', 'menu');
+
+    const systemItem = document.createElement('button');
+    systemItem.setAttribute('role', 'menuitemradio');
+    systemItem.setAttribute('aria-checked', 'false');
+    systemItem.innerHTML = `
+      <span class="mat-mdc-menu-item-text">
+        <span class="menu-item-title-with-trailing-component">
+          <span class="gds-label-l">系统</span>
+        </span>
+      </span>
+    `;
+    themeMenu.appendChild(systemItem);
+
+    const darkItem = document.createElement('button');
+    darkItem.setAttribute('role', 'menuitemradio');
+    darkItem.setAttribute('aria-checked', 'true');
+    darkItem.innerHTML = `
+      <span class="mat-mdc-menu-item-text">
+        <span class="menu-item-title-with-trailing-component">
+          <span class="gds-label-l">深色</span>
+        </span>
+      </span>
+    `;
+    themeMenu.appendChild(darkItem);
+
+    document.body.appendChild(themeMenu);
+
+    await Promise.resolve();
+    await vi.advanceTimersByTimeAsync(500);
+
+    // Star buttons should NOT be injected into theme menu items
+    expect(systemItem.querySelector('.gv-default-star-btn')).toBeNull();
+    expect(darkItem.querySelector('.gv-default-star-btn')).toBeNull();
+  });
+
   it('stops retrying after consecutive failures when target model is not found', async () => {
     // Set default model to a model that won't be found
     (chrome.storage.sync.get as unknown as ReturnType<typeof vi.fn>).mockImplementation(

src/pages/content/defaultModel/modelLocker.ts

@@ -19,6 +19,10 @@ const FAST_MODEL_NAMES = ['flash', '2.0 flash', 'gemini 2.0 flash', 'fast', '高
 // Gemini may use either role="menuitemradio" or role="menuitem" depending on the UI variant.
 const MODE_ITEM_SELECTOR = '[role="menuitemradio"], [role="menuitem"]';
 
+// Fallback selector that excludes known non-model menus (e.g. the settings/profile dropdown).
+const NON_MODEL_MENU_EXCLUSION_FALLBACK =
+  '.mat-mdc-menu-panel[role="menu"]:not(.desktop-settings-menu)';
+
 const CHAT_INPUT_SELECTORS = [
   'main rich-textarea [contenteditable="true"]',
   'rich-textarea [contenteditable="true"]',
@@ -184,15 +188,15 @@ class DefaultModelManager {
     if (
       root.matches('.mat-mdc-menu-panel.gds-mode-switch-menu[role="menu"]') ||
       root.matches('mat-action-list.gds-mode-switch-menu-list') ||
-      root.matches('.mat-mdc-menu-panel[role="menu"]')
+      root.matches(NON_MODEL_MENU_EXCLUSION_FALLBACK)
     ) {
       return root;
     }
 
     return (
       root.querySelector<HTMLElement>('.mat-mdc-menu-panel.gds-mode-switch-menu[role="menu"]') ??
       root.querySelector<HTMLElement>('mat-action-list.gds-mode-switch-menu-list') ??
-      root.querySelector<HTMLElement>('.mat-mdc-menu-panel[role="menu"]')
+      root.querySelector<HTMLElement>(NON_MODEL_MENU_EXCLUSION_FALLBACK)
     );
   }
 
@@ -202,7 +206,7 @@ class DefaultModelManager {
         '.mat-mdc-menu-panel.gds-mode-switch-menu[role="menu"]',
       ) ??
       document.querySelector<HTMLElement>('mat-action-list.gds-mode-switch-menu-list') ??
-      document.querySelector<HTMLElement>('.mat-mdc-menu-panel[role="menu"]')
+      document.querySelector<HTMLElement>(NON_MODEL_MENU_EXCLUSION_FALLBACK)
     );
   }
 
@@ -250,6 +254,15 @@ class DefaultModelManager {
     const items = menuPanel.querySelectorAll(MODE_ITEM_SELECTOR);
     if (!items.length) return false;
 
+    // Guard: only inject into menus that look like a model selector.
+    // Model menus always contain .title-and-description, .mode-title, or data-mode-id.
+    // Non-model menus (theme picker, help, etc.) lack these even if they use menuitemradio.
+    const isModelMenu =
+      menuPanel.querySelector('[data-mode-id]') !== null ||
+      menuPanel.querySelector('.mode-title') !== null ||
+      menuPanel.querySelector('.title-and-description') !== null;
+    if (!isModelMenu) return false;
+
     // Use cached value efficiently
     if (!this.initialized) {
       const result = await storageService.get<unknown>(StorageKeys.DEFAULT_MODEL);