@@ -0,0 +1,11 @@
+---
+'@object-ui/app-shell': patch
+'@object-ui/i18n': patch
+---
+
+fix(app-shell): an `object_extension` list row names and opens the object it extends
+
+Clause-②: no
+Metadata-protocol: none
+
+An `object_extension` item is stored under the name of the object it extends, and its body carries `extend` and no `name` (`ObjectExtensionSchema` refuses one). The metadata list read `name`, so in Studio's All metadata area a customization package's extension row showed "—" in its name cell and linked to `…/object_extension/(unnamed-0)`, an empty page. The type now declares `extend` as its identity key: the row shows the extended object (for example `showcase_task`) under an "Object" header, its link opens that extension in its own package, the search box matches it, and its customization mark is looked up by it. Rows of every other type are unchanged.
@@ -0,0 +1,240 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * objectstack#29569 — an `object_extension` row names, links and marks the
+ * object it extends.
+ *
+ * Measured on the card: the pair `com.example.showcase.custom` extended
+ * `showcase_task`, and the list read served the item as stored,
+ * `{ extend: 'showcase_task', fields, _packageId }`, with no `name`
+ * (`ObjectExtensionSchema` refuses one; the row is stored under the target's
+ * name). The list read `name`, so Studio's All metadata area drew the row as
+ * "—" and linked it to `…/object_extension/(unnamed-0)`, an empty page. The
+ * type now declares `extend` as its identity key (`default-schemas.ts`).
+ *
+ * Pinned, each against a control:
+ *
+ *  - in the cross-package leg the row shows `showcase_task` under an "Object"
+ *    header and links to that extension in its own package;
+ *  - in the base's area the row is found by `extend`, carries the pair's
+ *    "Added" mark, and its link addresses the extension, never `(unnamed-N)`;
+ *  - the mark is looked up by `extend`: a read listing the extension as an
+ *    override marks the row "Customized";
+ *  - the search box matches `extend`;
+ *  - the Label column shows the extension's own label;
+ *  - CONTROL: a row of another type (`page`) still names and links by `name`.
+ */
+
+import '@testing-library/jest-dom/vitest';
+import * as React from 'react';
+import { describe, it, expect, vi, afterEach, beforeEach } from 'vitest';
+import { render, screen, cleanup, within, fireEvent } from '@testing-library/react';
+import { MemoryRouter, Routes, Route, useLocation } from 'react-router-dom';
+// The switch column waits on `audienceAnchorsOf`'s dynamic import of this exact
+// specifier (see `ResourceListPage.environmentScope-7611.test.tsx`).
+import '@objectstack/spec/identity';
+import { MetadataAreaHostContext, type MetadataAreaHost } from './metadataAreaHost';
+
+const BASE = 'com.example.showcase';
+const PAIR = 'com.example.showcase.custom';
+
+/** What the list read serves: the extension body as stored, no `name`. */
+const LISTS: Record<string, Record<string, unknown>[]> = {
+  object_extension: [
+    {
+      extend: 'showcase_task',
+      label: 'Work items',
+      fields: { custom_note__c: { type: 'text', label: 'Custom note' } },
+      _packageId: PAIR,
+    },
+    { extend: 'showcase_project', fields: { budget_code__c: { type: 'text' } }, _packageId: PAIR },
+  ],
+  page: [{ name: 'task_board', label: 'Task board', _packageId: PAIR }],
+};
+
+/**
+ * The package list as served: the code-provided base and its writable pair, a
+ * project package, which the cross-package leg's list scopes to.
+ */
+const PACKAGES = [
+  { manifest: { id: BASE, name: 'Showcase', scope: 'installed' } },
+  { manifest: { id: PAIR, name: 'Showcase (custom)' } },
+];
+
+/** Stable singleton — the page's load effect keys on the client identity. */
+const CLIENT = {
+  list: async (type: string) => (type === 'package' ? PACKAGES : (LISTS[type] ?? [])),
+};
+
+const entry = (type: string, label: string) => ({
+  type,
+  label,
+  domain: 'data',
+  allowEnvironmentOverlay: false,
+  allowRuntimeCreate: true,
+});
+const ENTRIES = [entry('object_extension', 'Object Extension'), entry('page', 'Page')];
+
+vi.mock('./useMetadata', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  useMetadataClient: () => CLIENT,
+  useMetadataTypes: () => ({ loading: false, error: null, entries: ENTRIES }),
+}));
+vi.mock('./i18n', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  useMetadataLocale: () => 'en-US',
+}));
+vi.mock('../../hooks/useCanAuthorMetadata', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  useCanAuthorMetadata: () => true,
+}));
+
+import { MetadataResourceListPage } from './ResourceListPage';
+import { registerDefaultMetadataSchemas } from './default-schemas';
+import { t } from './i18n';
+
+registerDefaultMetadataSchemas();
+
+const EMPTY_COUNTS = { overrides: 0, extensions: 0, switchedOff: 0, contributions: 0 };
+/** The base's read as served on the card: the extension's field, no override. */
+const SERVED_READ = {
+  packageId: BASE,
+  overrides: [],
+  extensions: [{ object: 'showcase_task', kind: 'field', name: 'custom_note__c' }],
+  switchedOff: [],
+  contributions: [],
+  counts: { ...EMPTY_COUNTS, extensions: 1 },
+};
+let read: Record<string, unknown> = SERVED_READ;
+
+const fetchMock = vi.fn(async (url: string) => {
+  const json = (status: number, body: unknown) =>
+    new Response(JSON.stringify(body), { status, headers: { 'Content-Type': 'application/json' } });
+  const u = String(url);
+  if (u === '/api/v1/packages') {
+    return json(200, { success: true, data: { packages: [{ manifest: { id: BASE, name: 'Showcase', scope: 'installed' }, writable: false }] } });
+  }
+  if (/^\/api\/v1\/packages\/[^/]+\/customizations$/.test(u)) return json(200, { success: true, data: read });
+  if (u.startsWith('/api/v1/data/sys_metadata_activation')) {
+    return json(200, { object: 'sys_metadata_activation', records: [], hasMore: false });
+  }
+  return json(404, { success: false });
+});
+
+beforeEach(() => {
+  read = SERVED_READ;
+  fetchMock.mockClear();
+  vi.stubGlobal('fetch', fetchMock);
+});
+afterEach(() => {
+  cleanup();
+  vi.unstubAllGlobals();
+});
+
+const area = (packageId: string | null): MetadataAreaHost => ({
+  packageId,
+  readOnly: packageId !== null,
+  basePath: `/studio/${packageId ?? '~all'}/metadata`,
+});
+
+function Where() {
+  const loc = useLocation();
+  return <div data-testid="where">{loc.pathname + loc.search}</div>;
+}
+
+function mountList(host: MetadataAreaHost, type: string, search = '') {
+  return render(
+    <MetadataAreaHostContext.Provider value={host}>
+      <MemoryRouter initialEntries={[`${host.basePath}/${type}${search}`]}>
+        <Routes>
+          <Route path={`${host.basePath}/${type}`} element={<MetadataResourceListPage type={type} />} />
+          <Route path="*" element={<Where />} />
+        </Routes>
+      </MemoryRouter>
+    </MetadataAreaHostContext.Provider>,
+  );
+}
+
+const linkOf = (row: HTMLElement) => within(row).getAllByRole('link')[0]!;
+const marksOf = (row: HTMLElement) =>
+  within(row)
+    .queryAllByTestId('customization-mark')
+    .map((m) => m.getAttribute('data-kind'));
+
+describe('an object_extension row names, links and marks the object it extends (objectstack#29569)', () => {
+  it('the cross-package leg shows `extend` under an "Object" header and links to that extension', async () => {
+    mountList(area(null), 'object_extension');
+    const row = await screen.findByTestId('metadata-row-showcase_task');
+
+    const cells = within(row).getAllByRole('cell');
+    expect(cells[0]).toHaveTextContent('showcase_task');
+    expect(cells[0]).not.toHaveTextContent('—');
+    expect(screen.queryByTestId(/^metadata-row-\(unnamed-/)).toBeNull();
+    const headers = screen.getAllByRole('columnheader').map((h) => h.textContent?.trim());
+    expect(headers[0]).toBe(t('engine.list.col.extend', 'en-US'));
+    expect(t('engine.list.col.extend', 'en-US')).toBe('Object');
+
+    const href = linkOf(row).getAttribute('href') ?? '';
+    expect(href).toBe(`/studio/~all/metadata/object_extension/showcase_task?package=${encodeURIComponent(PAIR)}`);
+    fireEvent.click(linkOf(row));
+    expect(screen.getByTestId('where')).toHaveTextContent(
+      `/studio/~all/metadata/object_extension/showcase_task?package=${PAIR}`,
+    );
+  });
+
+  it("in the base's area the pair's row is found by `extend`, marked Added, and opens that extension", async () => {
+    mountList(area(BASE), 'object_extension', `?package=${BASE}`);
+    const row = await screen.findByTestId('metadata-row-showcase_task');
+    await within(row).findByTestId('customization-mark');
+
+    expect(within(row).getAllByRole('cell')[0]).toHaveTextContent('showcase_task');
+    expect(marksOf(row)).toEqual(['added']);
+    expect(linkOf(row).getAttribute('href')).toBe(
+      `/studio/${BASE}/metadata/object_extension/showcase_task?package=${encodeURIComponent(PAIR)}`,
+    );
+  });
+
+  it('the mark is looked up by `extend`: a read listing the extension as an override marks it Customized', async () => {
+    read = {
+      ...SERVED_READ,
+      overrides: [{ type: 'object_extension', name: 'showcase_task' }],
+      counts: { ...EMPTY_COUNTS, overrides: 1, extensions: 1 },
+    };
+    mountList(area(BASE), 'object_extension', `?package=${BASE}`);
+    const row = await screen.findByTestId('metadata-row-showcase_task');
+    await within(row).findByTestId('customization-mark');
+
+    expect(marksOf(row)).toEqual(['customized']);
+    // CONTROL: the other extension the read does not list stays "Added".
+    expect(marksOf(screen.getByTestId('metadata-row-showcase_project'))).toEqual(['added']);
+  });
+
+  it('the search box matches `extend`', async () => {
+    mountList(area(null), 'object_extension');
+    await screen.findByTestId('metadata-row-showcase_task');
+
+    fireEvent.change(screen.getByRole('textbox'), { target: { value: 'project' } });
+    expect(screen.getByTestId('metadata-row-showcase_project')).toBeInTheDocument();
+    expect(screen.queryByTestId('metadata-row-showcase_task')).toBeNull();
+  });
+
+  it("the Label column shows the extension's own label", async () => {
+    mountList(area(null), 'object_extension');
+    const row = await screen.findByTestId('metadata-row-showcase_task');
+
+    expect(within(row).getAllByRole('cell')[1]).toHaveTextContent('Work items');
+    expect(within(screen.getByTestId('metadata-row-showcase_project')).getAllByRole('cell')[1]).toHaveTextContent('—');
+  });
+
+  it('CONTROL: a row of another type still names and links by `name`', async () => {
+    mountList(area(null), 'page');
+    const row = await screen.findByTestId('metadata-row-task_board');
+
+    expect(within(row).getAllByRole('cell')[0]).toHaveTextContent('task_board');
+    expect(linkOf(row).getAttribute('href')).toBe(
+      `/studio/~all/metadata/page/task_board?package=${encodeURIComponent(PAIR)}`,
+    );
+    const headers = screen.getAllByRole('columnheader').map((h) => h.textContent?.trim());
+    expect(headers[0]).toBe(t('engine.list.col.name', 'en-US'));
+  });
+});
@@ -147,6 +147,8 @@ export const CONDITION_SCOPE_BY_METADATA_TYPE = {
   job: 'none',
   mapping: 'none',
   object: 'none',
+  /** objectstack#29569 registers `object_extension`; `ObjectExtensionSchema` declares no condition key. */
+  object_extension: 'none',
   position: 'none',
   report: 'none',
   skill: 'none',
 
@@ -362,4 +362,16 @@ export function registerDefaultMetadataSchemas(): void {
   // objectstack#26649 — two locales of one template are two members of one
   // name; the list tells them apart by `locale` and opens each by it.
   registerMetadataResource({ type: 'email_template', bundleMemberField: 'locale' });
+
+  // objectstack#29569 (ADR-0146 D10) — an `object_extension` is stored under
+  // the name of the object it extends, and its body carries `extend` and no
+  // `name` (`ObjectExtensionSchema` refuses one; the list read serves the body
+  // as stored). Its identity key is therefore `extend`: the list's name cell,
+  // its row link, its search and its customization mark all read it, so a row
+  // shows and opens the extended object instead of "—" and `(unnamed-N)`.
+  registerMetadataResource({
+    type: 'object_extension',
+    primaryKey: 'extend',
+    searchableFields: ['extend', 'label', 'description'],
+  });
 }
@@ -3620,6 +3620,8 @@ const STUDIO_EN: Record<string, string> = {
   'engine.list.col.label': 'Label',
   'engine.list.col.source': 'Source',
   'engine.list.col.object': 'Object',
+  // objectstack#29569 — an object_extension lists by the object it extends.
+  'engine.list.col.extend': 'Object',
   'engine.list.col.type': 'Type',
   'engine.list.col.description': 'Description',
   'engine.list.col.sharedWith': 'Shared with',
 
@@ -3218,6 +3218,8 @@ const STUDIO_ZH: Record<string, string> = {
   'engine.list.col.label': '标签',
   'engine.list.col.source': '来源',
   'engine.list.col.object': '对象',
+  // objectstack#29569 — an object_extension lists by the object it extends.
+  'engine.list.col.extend': '对象',
   'engine.list.col.type': '类型',
   'engine.list.col.description': '描述',
   'engine.list.col.sharedWith': '共享给',