feat: wiki like linkage for posts

src/renderer/components/Editor/Editor.tsx

@@ -847,6 +847,8 @@ export const PostEditor: React.FC<PostEditorProps> = ({ postId }) => {
               content={content}
               onChange={setContent}
               placeholder={tr('editor.placeholder.startWriting')}
+              currentPostTags={tags}
+              currentPostCategories={selectedCategories}
             />
           )}
           
@@ -921,6 +923,8 @@ export const PostEditor: React.FC<PostEditorProps> = ({ postId }) => {
           onInsertLink={handleInsertLink}
           onInsertImage={() => {}}
           onClose={() => setShowPostSearch(false)}
+          currentPostTags={tags}
+          currentPostCategories={selectedCategories}
         />
       )}
       

src/renderer/components/InsertModal/InsertModal.css

@@ -240,3 +240,58 @@
 .insert-modal-results::-webkit-scrollbar-thumb:hover {
   background: var(--color-text-muted, #555);
 }
+
+/* Create post option */
+.insert-modal-result-create {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  width: 100%;
+  padding: 12px 16px;
+  border: none;
+  border-top: 1px solid var(--color-border, #3c3c3c);
+  margin-top: 4px;
+  padding-top: 16px;
+  background: transparent;
+  color: var(--vscode-notificationsInfoIcon-foreground, #75beff);
+  font-family: inherit;
+  font-size: 14px;
+  text-align: left;
+  cursor: pointer;
+  border-radius: 0 0 4px 4px;
+  transition: background-color 0.15s ease;
+}
+
+.insert-modal-result-create:first-child {
+  border-top: none;
+  margin-top: 0;
+  padding-top: 12px;
+}
+
+.insert-modal-result-create:hover,
+.insert-modal-result-create.selected {
+  background: var(--color-bg-tertiary, #2a2a2a);
+}
+
+.insert-modal-result-create.selected {
+  border-left: 3px solid var(--vscode-notificationsInfoIcon-foreground, #75beff);
+  padding-left: 13px;
+}
+
+.insert-modal-result-create:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+}
+
+.insert-modal-create-icon {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  width: 18px;
+  height: 18px;
+  border: 1px dashed currentColor;
+  border-radius: 4px;
+  font-size: 14px;
+  font-weight: 600;
+  flex-shrink: 0;
+}

src/renderer/components/InsertModal/InsertModal.tsx

@@ -1,5 +1,7 @@
 import React, { useCallback, useEffect, useRef, useState } from 'react';
 import { useI18n } from '../../i18n';
+import { useAppStore } from '../../store/appStore';
+import { showToast } from '../Toast';
 import './InsertModal.css';
 
 interface PostSearchResult {
@@ -20,8 +22,8 @@ interface MediaSearchResult {
 /** Get display name for media: title (truncated to 60 chars) or fallback to filename */
 function getMediaDisplayName(media: MediaSearchResult): string {
   if (media.title) {
-    return media.title.length > 60 
+    return media.title.length > 60
-      ? media.title.substring(0, 60) + '...' 
+      ? media.title.substring(0, 60) + '...'
       : media.title;
   }
   return media.originalName;
@@ -38,6 +40,8 @@ interface InsertModalProps {
   onInsertImage: (url: string, alt: string, mediaId?: string) => void;
   onClose: () => void;
   initialText?: string; // Selected text in editor
+  currentPostTags?: string[];
+  currentPostCategories?: string[];
 }
 
 function isPostResult(result: SearchResult): result is PostSearchResult {
@@ -54,8 +58,11 @@ export const InsertModal: React.FC<InsertModalProps> = ({
   onInsertImage,
   onClose,
   initialText = '',
+  currentPostTags,
+  currentPostCategories,
 }) => {
   const { t: tr } = useI18n();
+  const openTabInBackground = useAppStore((s) => s.openTabInBackground);
   const [activeTab, setActiveTab] = useState<Tab>('internal');
   const [query, setQuery] = useState('');
   const [externalUrl, setExternalUrl] = useState('');
@@ -64,9 +71,20 @@ export const InsertModal: React.FC<InsertModalProps> = ({
   const [results, setResults] = useState<SearchResult[]>([]);
   const [selectedIndex, setSelectedIndex] = useState(0);
   const [isSearching, setIsSearching] = useState(false);
+  const [isCreating, setIsCreating] = useState(false);
   const inputRef = useRef<HTMLInputElement>(null);
   const externalUrlRef = useRef<HTMLInputElement>(null);
 
+  // Whether to show the "Create post" option
+  const showCreateOption = mode === 'link' &&
+    activeTab === 'internal' &&
+    query.trim().length >= 2 &&
+    !isSearching &&
+    !results.some(r => isPostResult(r) && r.title.toLowerCase() === query.trim().toLowerCase());
+
+  // Total selectable items count (results + optional create option)
+  const totalItems = results.length + (showCreateOption ? 1 : 0);
+
   // Focus appropriate input on mount and tab change
   useEffect(() => {
     if (activeTab === 'internal') {
@@ -106,6 +124,34 @@ export const InsertModal: React.FC<InsertModalProps> = ({
     return () => clearTimeout(timeoutId);
   }, [query, mode, activeTab]);
 
+  // Handle creating a new post from the search query
+  const handleCreatePost = useCallback(async () => {
+    const title = query.trim();
+    if (!title || isCreating) return;
+
+    setIsCreating(true);
+    try {
+      const newPost = await window.electronAPI.posts.create({
+        title,
+        tags: currentPostTags || [],
+        categories: currentPostCategories || [],
+      });
+
+      if (newPost) {
+        openTabInBackground({ type: 'post', id: newPost.id, isTransient: false });
+        const linkUrl = `/posts/${newPost.slug}`;
+        onInsertLink(linkUrl, title);
+        showToast.success(tr('insert.createdPost', { title }));
+        onClose();
+      }
+    } catch (error) {
+      const err = error as Error;
+      showToast.error(err.message);
+    } finally {
+      setIsCreating(false);
+    }
+  }, [query, isCreating, currentPostTags, currentPostCategories, openTabInBackground, onInsertLink, onClose, tr]);
+
   // Keyboard navigation handler
   const handleKeyDown = useCallback((e: React.KeyboardEvent) => {
     switch (e.key) {
@@ -116,7 +162,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
       case 'ArrowDown':
         if (activeTab === 'internal') {
           e.preventDefault();
-          setSelectedIndex(prev => Math.min(prev + 1, results.length - 1));
+          setSelectedIndex(prev => Math.min(prev + 1, totalItems - 1));
         }
         break;
       case 'ArrowUp':
@@ -127,9 +173,13 @@ export const InsertModal: React.FC<InsertModalProps> = ({
         break;
       case 'Enter':
         e.preventDefault();
-        if (activeTab === 'internal' && results[selectedIndex]) {
+        if (activeTab === 'internal') {
-          handleSelectResult(results[selectedIndex]);
+          if (selectedIndex < results.length && results[selectedIndex]) {
-        } else if (activeTab === 'external' && externalUrl) {
+            handleSelectResult(results[selectedIndex]);
+          } else if (showCreateOption && selectedIndex === results.length) {
+            handleCreatePost();
+          }
+        } else if (externalUrl) {
           handleExternalSubmit();
         }
         break;
@@ -137,7 +187,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
         // Allow tab switching with Tab key when on the tab buttons
         break;
     }
-  }, [activeTab, results, selectedIndex, externalUrl, onClose]);
+  }, [activeTab, results, selectedIndex, totalItems, showCreateOption, externalUrl, onClose, handleCreatePost]);
 
   // Handle selecting a search result
   const handleSelectResult = useCallback(async (result: SearchResult) => {
@@ -161,7 +211,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
   // Handle external URL submission
   const handleExternalSubmit = useCallback(() => {
     if (!externalUrl) return;
-    
+
     if (mode === 'link') {
       onInsertLink(externalUrl, externalText || undefined);
     } else {
@@ -180,7 +230,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
 
   // Scroll selected item into view
   useEffect(() => {
-    const selectedElement = document.querySelector('.insert-modal-result-item.selected');
+    const selectedElement = document.querySelector('.insert-modal-result-item.selected, .insert-modal-result-create.selected');
     if (selectedElement) {
       selectedElement.scrollIntoView({ block: 'nearest', behavior: 'smooth' });
     }
@@ -189,7 +239,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
   const title = mode === 'link' ? tr('insert.title.link') : tr('insert.title.image');
   const internalLabel = mode === 'link' ? tr('insert.tab.linkInternal') : tr('insert.tab.imageInternal');
   const externalLabel = mode === 'link' ? tr('insert.tab.linkExternal') : tr('insert.tab.imageExternal');
-  const searchPlaceholder = mode === 'link' 
+  const searchPlaceholder = mode === 'link'
     ? tr('insert.searchPlaceholder.link')
     : tr('insert.searchPlaceholder.image');
 
@@ -224,6 +274,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
                 placeholder={searchPlaceholder}
                 value={query}
                 onChange={(e) => setQuery(e.target.value)}
+                onInput={(e) => setQuery((e.target as HTMLInputElement).value)}
                 autoComplete="off"
               />
             </div>
@@ -239,7 +290,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
                 </div>
               )}
 
-              {!isSearching && query.length >= 2 && results.length === 0 && (
+              {!isSearching && query.length >= 2 && results.length === 0 && !showCreateOption && (
                 <div className="insert-modal-status">
                   {tr('insert.status.noResults', { kind: mode === 'link' ? tr('activity.posts').toLowerCase() : tr('activity.media').toLowerCase(), query })}
                 </div>
@@ -274,6 +325,19 @@ export const InsertModal: React.FC<InsertModalProps> = ({
                   )}
                 </div>
               ))}
+
+              {showCreateOption && (
+                <button
+                  type="button"
+                  className={`insert-modal-result-create ${selectedIndex === results.length ? 'selected' : ''}`}
+                  onClick={handleCreatePost}
+                  onMouseEnter={() => setSelectedIndex(results.length)}
+                  disabled={isCreating}
+                >
+                  <span className="insert-modal-create-icon">+</span>
+                  <span>{tr('insert.createPost', { title: query.trim() })}</span>
+                </button>
+              )}
             </div>
           </>
         ) : (
@@ -290,7 +354,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
                 autoComplete="off"
               />
             </div>
-            
+
             {mode === 'link' ? (
               <div className="insert-modal-field">
                 <label className="insert-modal-label">{tr('insert.label.linkTextOptional')}</label>
@@ -328,7 +392,7 @@ export const InsertModal: React.FC<InsertModalProps> = ({
         <div className="insert-modal-footer">
           <div className="insert-modal-footer-content">
             <span className="insert-modal-hint">
-              {activeTab === 'internal' 
+              {activeTab === 'internal'
                 ? tr('insert.hint.internal')
                 : tr('insert.hint.external')}
             </span>

src/renderer/components/MilkdownEditor/MilkdownEditor.tsx

@@ -54,6 +54,8 @@ interface MilkdownEditorProps {
   content: string;
   onChange: (markdown: string) => void;
   placeholder?: string;
+  currentPostTags?: string[];
+  currentPostCategories?: string[];
 }
 
 interface MilkdownChangePropagationInput {
@@ -86,10 +88,12 @@ export const shouldPropagateMilkdownChange = ({
 
 interface EditorToolbarProps {
   onUserInteraction: () => void;
+  currentPostTags?: string[];
+  currentPostCategories?: string[];
 }
 
 // Toolbar component that uses the editor instance
-const EditorToolbar: React.FC<EditorToolbarProps> = ({ onUserInteraction }) => {
+const EditorToolbar: React.FC<EditorToolbarProps> = ({ onUserInteraction, currentPostTags, currentPostCategories }) => {
   const { t: tr } = useI18n();
   const [loading, getEditor] = useInstance();
   const [insertMode, setInsertMode] = useState<InsertModalMode>(null);
@@ -269,6 +273,8 @@ const EditorToolbar: React.FC<EditorToolbarProps> = ({ onUserInteraction }) => {
           onInsertImage={handleInsertImage}
           onClose={() => setInsertMode(null)}
           initialText={selectedText}
+          currentPostTags={currentPostTags}
+          currentPostCategories={currentPostCategories}
         />
       )}
     </>
@@ -289,6 +295,8 @@ const MilkdownProviderInner: React.FC<MilkdownEditorProps> = ({
   content,
   onChange,
   placeholder,
+  currentPostTags,
+  currentPostCategories,
 }) => {
   const { t: tr } = useI18n();
   const resolvedPlaceholder = placeholder || tr('editor.placeholder');
@@ -376,7 +384,7 @@ const MilkdownProviderInner: React.FC<MilkdownEditorProps> = ({
       onPasteCapture={markUserInteraction}
       onInputCapture={markUserInteraction}
     >
-      <EditorToolbar onUserInteraction={markUserInteraction} />
+      <EditorToolbar onUserInteraction={markUserInteraction} currentPostTags={currentPostTags} currentPostCategories={currentPostCategories} />
       <div className="milkdown-content" data-placeholder={resolvedPlaceholder}>
         <Milkdown />
       </div>

src/renderer/i18n/locales/de.json

@@ -248,6 +248,8 @@
   "insert.hint.external": "URL eingeben und Enter drücken oder auf die Schaltfläche klicken, Esc zum Schließen",
   "insert.hint.canonicalPost": "Kanonisch: /YYYY/MM/DD/slug",
   "insert.hint.canonicalMedia": "Kanonisch: /media/YYYY/MM/datei.ext",
+  "insert.createPost": "Beitrag \"{title}\" erstellen",
+  "insert.createdPost": "Beitrag \"{title}\" erstellt",
   "postLinks.loading": "Links werden geladen...",
   "postLinks.link": "Link",
   "postLinks.links": "Links",

src/renderer/i18n/locales/en.json

@@ -248,6 +248,8 @@
   "insert.hint.external": "Enter URL and press Enter or click button, Esc to close",
   "insert.hint.canonicalPost": "Canonical: /YYYY/MM/DD/slug",
   "insert.hint.canonicalMedia": "Canonical: /media/YYYY/MM/file.ext",
+  "insert.createPost": "Create post \"{title}\"",
+  "insert.createdPost": "Post \"{title}\" created",
   "postLinks.loading": "Loading links...",
   "postLinks.link": "link",
   "postLinks.links": "links",

src/renderer/i18n/locales/es.json

@@ -248,6 +248,8 @@
   "insert.hint.external": "Introduce la URL y pulsa Enter o haz clic en el botón, Esc para cerrar",
   "insert.hint.canonicalPost": "Canónico: /YYYY/MM/DD/slug",
   "insert.hint.canonicalMedia": "Canónico: /media/YYYY/MM/archivo.ext",
+  "insert.createPost": "Crear artículo \"{title}\"",
+  "insert.createdPost": "Artículo \"{title}\" creado",
   "postLinks.loading": "Cargando enlaces...",
   "postLinks.link": "enlace",
   "postLinks.links": "enlaces",

src/renderer/i18n/locales/fr.json

@@ -246,6 +246,8 @@
   "insert.hint.external": "Entrez l’URL et appuyez sur Entrée ou cliquez sur le bouton, Esc pour fermer",
   "insert.hint.canonicalPost": "Canonique : /YYYY/MM/DD/slug",
   "insert.hint.canonicalMedia": "Canonique : /media/YYYY/MM/fichier.ext",
+  "insert.createPost": "Créer l'article « {title} »",
+  "insert.createdPost": "Article « {title} » créé",
   "postLinks.loading": "Chargement des liens...",
   "postLinks.link": "lien",
   "postLinks.links": "liens",

src/renderer/i18n/locales/it.json

@@ -246,6 +246,8 @@
   "insert.hint.external": "Inserisci URL e premi Invio o clicca il pulsante, Esc per chiudere",
   "insert.hint.canonicalPost": "Canonico: /YYYY/MM/DD/slug",
   "insert.hint.canonicalMedia": "Canonico: /media/YYYY/MM/file.ext",
+  "insert.createPost": "Crea articolo \"{title}\"",
+  "insert.createdPost": "Articolo \"{title}\" creato",
   "postLinks.loading": "Caricamento link...",
   "postLinks.link": "collegamento",
   "postLinks.links": "link",

src/renderer/store/appStore.ts

@@ -118,6 +118,7 @@ interface AppState {
   
   // Tab Actions
   openTab: (tab: { type: TabType; id: string; isTransient: boolean }) => void;
+  openTabInBackground: (tab: { type: TabType; id: string; isTransient: boolean }) => void;
   closeTab: (id: string) => void;
   setActiveTab: (id: string) => void;
   pinTab: (id: string) => void;
@@ -274,7 +275,23 @@ export const useAppStore = create<AppState>()(
         const newTab: Tab = { type, id, isTransient };
         return { tabs: [...state.tabs, newTab], activeTabId: id };
       }),
-      
+
+      openTabInBackground: ({ type, id, isTransient }) => set((state) => {
+        const existingTabIndex = state.tabs.findIndex((t) => t.id === id && t.type === type);
+
+        if (existingTabIndex >= 0) {
+          if (!isTransient) {
+            const updatedTabs = [...state.tabs];
+            updatedTabs[existingTabIndex] = { ...updatedTabs[existingTabIndex], isTransient: false };
+            return { tabs: updatedTabs };
+          }
+          return state;
+        }
+
+        const newTab: Tab = { type, id, isTransient };
+        return { tabs: [...state.tabs, newTab] };
+      }),
+
       closeTab: (id) => set((state) => {
         const tabIndex = state.tabs.findIndex((t) => t.id === id);
         if (tabIndex === -1) return state;

tests/renderer/components/InsertModal.test.tsx

@@ -1,7 +1,8 @@
 import React from 'react';
-import { describe, it, expect, vi } from 'vitest';
+import { describe, it, expect, vi, beforeEach } from 'vitest';
-import { render, screen } from '@testing-library/react';
+import { render, screen, fireEvent, act } from '@testing-library/react';
 import { InsertModal } from '../../../src/renderer/components/InsertModal/InsertModal';
+import { useAppStore } from '../../../src/renderer/store/appStore';
 
 describe('InsertModal format hints', () => {
   it('shows canonical post link format hint in internal link mode', () => {
@@ -30,3 +31,170 @@ describe('InsertModal format hints', () => {
     expect(screen.getByText('Canonical: /media/YYYY/MM/file.ext')).toBeInTheDocument();
   });
 });
+
+describe('InsertModal create post', () => {
+  const mockOnInsertLink = vi.fn();
+  const mockOnClose = vi.fn();
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    useAppStore.setState({ tabs: [], activeTabId: 'current-post' });
+  });
+
+  it('does not show create option when query is shorter than 2 characters', () => {
+    render(
+      <InsertModal
+        mode="link"
+        onInsertLink={mockOnInsertLink}
+        onInsertImage={vi.fn()}
+        onClose={mockOnClose}
+      />
+    );
+
+    const input = screen.getByPlaceholderText('Search posts by title or content...');
+    fireEvent.input(input, { target: { value: 'a' } });
+
+    expect(screen.queryByText(/Create post/)).not.toBeInTheDocument();
+  });
+
+  it('does not show create option in image mode', async () => {
+    (window.electronAPI.media.search as ReturnType<typeof vi.fn>).mockResolvedValue([]);
+
+    render(
+      <InsertModal
+        mode="image"
+        onInsertLink={vi.fn()}
+        onInsertImage={vi.fn()}
+        onClose={mockOnClose}
+      />
+    );
+
+    const input = screen.getByPlaceholderText('Search media by name, title, or alt text...');
+    fireEvent.input(input, { target: { value: 'test query' } });
+
+    // Wait for search to complete by finding the no-results message
+    await screen.findByText(/No.*found/i);
+
+    expect(screen.queryByText(/Create post/)).not.toBeInTheDocument();
+  });
+
+  it('shows create option when search has no exact title match', async () => {
+    (window.electronAPI.posts.search as ReturnType<typeof vi.fn>).mockResolvedValue([
+      { id: 'p1', title: 'Different Title', slug: 'different-title', excerpt: 'Some text' },
+    ]);
+
+    render(
+      <InsertModal
+        mode="link"
+        onInsertLink={mockOnInsertLink}
+        onInsertImage={vi.fn()}
+        onClose={mockOnClose}
+      />
+    );
+
+    const input = screen.getByPlaceholderText('Search posts by title or content...');
+    fireEvent.input(input, { target: { value: 'My New Post' } });
+
+    // Wait for search results to render
+    await screen.findByText('Different Title');
+
+    expect(screen.getByText('Create post "My New Post"')).toBeInTheDocument();
+  });
+
+  it('does not show create option when an exact title match exists', async () => {
+    (window.electronAPI.posts.search as ReturnType<typeof vi.fn>).mockResolvedValue([
+      { id: 'p1', title: 'My New Post', slug: 'my-new-post', excerpt: '' },
+    ]);
+
+    render(
+      <InsertModal
+        mode="link"
+        onInsertLink={mockOnInsertLink}
+        onInsertImage={vi.fn()}
+        onClose={mockOnClose}
+      />
+    );
+
+    const input = screen.getByPlaceholderText('Search posts by title or content...');
+    fireEvent.input(input, { target: { value: 'My New Post' } });
+
+    // Wait for results to render (slug appears in the result path)
+    await screen.findByText(/my-new-post/);
+
+    expect(screen.queryByText('Create post "My New Post"')).not.toBeInTheDocument();
+  });
+
+  it('creates post and inserts link when create option is clicked', async () => {
+    (window.electronAPI.posts.search as ReturnType<typeof vi.fn>).mockResolvedValue([]);
+    (window.electronAPI.posts.create as ReturnType<typeof vi.fn>).mockResolvedValue({
+      id: 'new-post-id',
+      title: 'New Post Title',
+      slug: 'new-post-title',
+      content: '',
+      status: 'draft',
+      tags: ['tag1'],
+      categories: ['article'],
+      createdAt: new Date().toISOString(),
+      updatedAt: new Date().toISOString(),
+    });
+
+    render(
+      <InsertModal
+        mode="link"
+        onInsertLink={mockOnInsertLink}
+        onInsertImage={vi.fn()}
+        onClose={mockOnClose}
+        currentPostTags={['tag1']}
+        currentPostCategories={['article']}
+      />
+    );
+
+    const input = screen.getByPlaceholderText('Search posts by title or content...');
+    fireEvent.input(input, { target: { value: 'New Post Title' } });
+
+    // Wait for the create option to appear after debounced search completes
+    const createButton = await screen.findByText('Create post "New Post Title"');
+
+    await act(async () => {
+      fireEvent.click(createButton);
+    });
+
+    expect(window.electronAPI.posts.create).toHaveBeenCalledWith({
+      title: 'New Post Title',
+      tags: ['tag1'],
+      categories: ['article'],
+    });
+
+    expect(mockOnInsertLink).toHaveBeenCalledWith('/posts/new-post-title', 'New Post Title');
+    expect(mockOnClose).toHaveBeenCalled();
+
+    // Check that the tab was opened in the background
+    const storeState = useAppStore.getState();
+    expect(storeState.tabs).toContainEqual(
+      expect.objectContaining({ type: 'post', id: 'new-post-id', isTransient: false })
+    );
+    expect(storeState.activeTabId).toBe('current-post');
+  });
+
+  it('shows create option when no results exist (standalone)', async () => {
+    (window.electronAPI.posts.search as ReturnType<typeof vi.fn>).mockResolvedValue([]);
+
+    render(
+      <InsertModal
+        mode="link"
+        onInsertLink={mockOnInsertLink}
+        onInsertImage={vi.fn()}
+        onClose={mockOnClose}
+      />
+    );
+
+    const input = screen.getByPlaceholderText('Search posts by title or content...');
+    fireEvent.input(input, { target: { value: 'Nonexistent Post' } });
+
+    // Wait for create option to appear (replaces no-results message)
+    expect(await screen.findByText('Create post "Nonexistent Post"')).toBeInTheDocument();
+
+    // The "no results" message should not appear when create option is shown
+    expect(screen.queryByText(/No posts found/i)).not.toBeInTheDocument();
+  });
+});

tests/renderer/store/appStore.test.ts

@@ -215,4 +215,50 @@ describe('AppStore', () => {
       expectTypeOf<TaskProgress>().toEqualTypeOf<SharedTaskProgress>();
     });
   });
+
+  describe('Tab Management', () => {
+    beforeEach(() => {
+      setState({
+        tabs: [],
+        activeTabId: null,
+      });
+    });
+
+    it('should open a tab in the background without changing activeTabId', () => {
+      // Set up an existing active tab
+      getStore().openTab({ type: 'post', id: 'existing-post', isTransient: false });
+      expect(getStore().activeTabId).toBe('existing-post');
+
+      // Open a new tab in the background
+      getStore().openTabInBackground({ type: 'post', id: 'background-post', isTransient: false });
+
+      expect(getStore().tabs).toHaveLength(2);
+      expect(getStore().tabs[1].id).toBe('background-post');
+      expect(getStore().activeTabId).toBe('existing-post');
+    });
+
+    it('should not duplicate a tab when opening in background if it already exists', () => {
+      getStore().openTab({ type: 'post', id: 'post-1', isTransient: false });
+      getStore().openTabInBackground({ type: 'post', id: 'post-1', isTransient: false });
+
+      expect(getStore().tabs).toHaveLength(1);
+    });
+
+    it('should pin an existing transient tab when opening in background as non-transient', () => {
+      getStore().openTab({ type: 'post', id: 'post-1', isTransient: true });
+      getStore().openTabInBackground({ type: 'post', id: 'post-1', isTransient: false });
+
+      expect(getStore().tabs).toHaveLength(1);
+      expect(getStore().tabs[0].isTransient).toBe(false);
+    });
+
+    it('should preserve null activeTabId when opening background tab with no prior active tab', () => {
+      setState({ activeTabId: null, tabs: [] });
+
+      getStore().openTabInBackground({ type: 'post', id: 'bg-post', isTransient: false });
+
+      expect(getStore().tabs).toHaveLength(1);
+      expect(getStore().activeTabId).toBeNull();
+    });
+  });
 });