@@ -0,0 +1,10 @@
+---
+'@object-ui/i18n': patch
+---
+
+feat(i18n): the rest of the Studio strings and the metadata preview panes move into the `studio` namespace
+
+Clause-②: no
+Metadata-protocol: none
+
+- **Fifth slice of the move ruled on objectstack#25922** (6431032267, Q2 = A; kept by 6431234244). Every remaining `engine.studio.*` key except `engine.studio.inspector.*`, and the preview panes' `engine.*Preview.*` and `engine.previewShell.*` keys (the doc, book, flow, page-block and translation previews stay for a later slice), 596 keys in both `en` and `zh`, now live in `@object-ui/i18n/namespaces/studio` instead of `@object-ui/app-shell`'s private table, text unchanged. Studio reads the same strings; a Chinese viewer sees these labels in English for the moment the `zh` catalogue takes to load, as with the earlier slices. No export changes.
@@ -1,12 +1,12 @@
 // Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
 
 /**
- * objectstack#25922 slices S2 to S4 — the designer rows that moved into
+ * objectstack#25922 slices S2 to S5 — the designer rows that moved into
  * `@object-ui/i18n`'s `studio` namespace (every `engine.inspector.*` row;
- * `engine.packages.*`, `engine.form.*`, `engine.edit.*`; five `engine.studio.*`
- * pillars, the data source pages and the field types), and app-shell's `t()` /
- * `tOptional()` still answer every one of them the way they did when the rows
- * sat in its own table.
+ * `engine.packages.*`, `engine.form.*`, `engine.edit.*`; `engine.studio.*` but
+ * its inspector; the data source pages, the field types and the metadata
+ * preview panes), and app-shell's `t()` / `tOptional()` still answer every one
+ * of them the way they did when the rows sat in its own table.
  *
  * What would break it:
  *   - a row copied back into the app-shell table with a different value — the
@@ -54,6 +54,30 @@ const FAMILY_FLOOR: Readonly<Record<string, number>> = Object.freeze({
   'engine.fieldType.': 45,
   'engine.fieldTypeDesc.': 45,
   'engine.fieldCategory.': 9,
+  // S5 — the rest of engine.studio (its inspector aside) and the preview panes
+  'engine.studio.': 600,
+  'engine.studio.rules.': 55,
+  'engine.studio.interfaces.': 30,
+  'engine.studio.designer.': 20,
+  'engine.actionPreview.': 50,
+  'engine.permissionPreview.': 35,
+  'engine.validationPreview.': 30,
+  'engine.jobPreview.': 18,
+  'engine.agentPreview.': 15,
+  'engine.skillPreview.': 15,
+  'engine.datasetPreview.': 12,
+  'engine.toolPreview.': 12,
+  'engine.picklistPreview.': 12,
+  'engine.dashboardPreview.': 9,
+  'engine.appPreview.': 9,
+  'engine.emailTemplatePreview.': 9,
+  'engine.pagePreview.': 8,
+  'engine.screenPreview.': 7,
+  'engine.positionPreview.': 6,
+  'engine.reportPreview.': 6,
+  'engine.viewPreview.': 4,
+  'engine.objectPreview.': 1,
+  'engine.previewShell.': 1,
 });
 
 /**
 
@@ -23,6 +23,12 @@ import { render, screen, cleanup } from '@testing-library/react';
 import { t } from '../i18n';
 import { AppPreview } from './AppPreview';
 
+// The designer rows this suite reads in zh live in `@object-ui/i18n`'s `studio`
+// namespace, whose `zh` catalogue is fetched on demand (objectstack#25922).
+// Resident before any case, so the zh rows below read synchronously.
+import { loadStudioCatalogue } from '@object-ui/i18n/namespaces/studio';
+await loadStudioCatalogue('zh');
+
 afterEach(cleanup);
 
 const NAV = [{ id: 'accounts', type: 'object', label: 'Accounts', objectName: 'account' }];
 
@@ -38,6 +38,12 @@ vi.mock('@object-ui/react', async (importOriginal) => {
 import { DashboardPreview } from './DashboardPreview';
 import type { MetadataSelection } from '../preview-registry';
 
+// The designer rows this suite reads in zh live in `@object-ui/i18n`'s `studio`
+// namespace, whose `zh` catalogue is fetched on demand (objectstack#25922).
+// Resident before any case, so the zh rows below read synchronously.
+import { loadStudioCatalogue } from '@object-ui/i18n/namespaces/studio';
+await loadStudioCatalogue('zh');
+
 afterEach(cleanup);
 
 type Patch = Record<string, unknown>;
 
@@ -32,6 +32,12 @@ import { ScreenPreview } from './ScreenPreview';
 import { buildScreenSpec } from './screen-spec';
 import { ScreenView, initialScreenValues, type ScreenFieldSpec, type ScreenSpec } from '../../ScreenView';
 
+// The designer rows this suite reads in zh live in `@object-ui/i18n`'s `studio`
+// namespace, whose `zh` catalogue is fetched on demand (objectstack#25922).
+// Resident before any case, so the zh rows below read synchronously.
+import { loadStudioCatalogue } from '@object-ui/i18n/namespaces/studio';
+await loadStudioCatalogue('zh');
+
 afterEach(cleanup);
 
 /**
 
@@ -40,6 +40,12 @@ import { SkillPreview } from './SkillPreview';
 import { ToolPreview } from './ToolPreview';
 import { JobPreview } from './JobPreview';
 
+// The designer rows this suite reads in zh live in `@object-ui/i18n`'s `studio`
+// namespace, whose `zh` catalogue is fetched on demand (objectstack#25922).
+// Resident before any case, so the zh rows below read synchronously.
+import { loadStudioCatalogue } from '@object-ui/i18n/namespaces/studio';
+await loadStudioCatalogue('zh');
+
 afterEach(() => {
   cleanup();
   vi.unstubAllGlobals();
 
@@ -99,6 +99,12 @@ import { FlowSimulatorPanel } from './FlowSimulatorPanel';
 import { FlowNodeInspector } from '../inspectors/FlowNodeInspector';
 import type { SimEdge, SimNode } from './simulator/flow-sim-types';
 
+// The designer rows this suite reads in zh live in `@object-ui/i18n`'s `studio`
+// namespace, whose `zh` catalogue is fetched on demand (objectstack#25922).
+// Resident before any case, so the zh rows below read synchronously.
+import { loadStudioCatalogue } from '@object-ui/i18n/namespaces/studio';
+await loadStudioCatalogue('zh');
+
 afterEach(() => {
   cleanup();
   state.canvas = 'draw';
 
@@ -23,6 +23,12 @@ import { createI18n, I18nProvider } from '@object-ui/i18n';
 import { t } from './i18n';
 import { AppNavCanvas } from './previews/AppNavCanvas';
 
+// The designer rows this suite reads in zh live in `@object-ui/i18n`'s `studio`
+// namespace, whose `zh` catalogue is fetched on demand (objectstack#25922).
+// Resident before any case, so the zh rows below read synchronously.
+import { loadStudioCatalogue } from '@object-ui/i18n/namespaces/studio';
+await loadStudioCatalogue('zh');
+
 afterEach(cleanup);
 
 // Representative keys spanning shared chrome, every pillar, and AppNavCanvas.
 
@@ -4,21 +4,24 @@
  * objectstack#25922, (M) slice 1 — a Studio designer screen reads the strings
  * that moved into `@object-ui/i18n`'s `studio` namespace.
  *
- * The Data pillar's "Add field" popover mixes both homes on one screen: its
- * field labels (`designer.field.label` / `.apiName` / `.type`) moved into the
- * namespace, its Cancel button (`engine.studio.cancel`) is still in the
- * app-shell table (its title and Create button followed in slice S4). It takes its locale from `useMetadataLocale()`, the hook
- * every designer component uses, so this is the path a real screen takes:
+ * The Data pillar's "Add field" popover reads the namespace through both
+ * doors: its field labels (`designer.field.label` / `.apiName` / `.type`,
+ * slice 1) straight from it, its chrome (`engine.studio.*`, slices S4 and S5)
+ * through app-shell's `t()`, which answers from the namespace once the
+ * designer table no longer holds the row. It takes its locale from
+ * `useMetadataLocale()`, the hook every designer component uses, so this is
+ * the path a real screen takes:
  *
  *   - zh: the namespace's `zh` catalogue is NOT resident when the screen first
  *     renders (this file runs in an isolated `dom` project and preloads
  *     nothing). The first paint reads the moved labels in English — the
  *     fallback, never the raw key — and the same mount re-renders in Chinese
- *     once the catalogue lands. The table's keys read Chinese throughout.
- *   - de: a language neither home ships renders English from both.
+ *     once the catalogue lands, chrome included.
+ *   - de: a language the namespace does not ship renders English through both
+ *     doors.
  *
- * Expectations are read from the namespace and the table rather than typed
- * out, so no case restates a translation.
+ * Expectations are read from the namespace and `t()` rather than typed out, so
+ * no case restates a translation.
  */
 
 import '@testing-library/jest-dom/vitest';
@@ -39,8 +42,8 @@ afterEach(cleanup);
 
 /** Keys this screen renders from the namespace. */
 const MOVED = ['designer.field.label', 'designer.field.type'] as const;
-/** A key this screen renders from the app-shell table. */
-const TABLE = 'engine.studio.cancel';
+/** A chrome key this screen reads through app-shell's `t()`. */
+const CHROME = 'engine.studio.cancel';
 
 function Screen({ lang }: { lang: string }) {
   return (
@@ -58,9 +61,8 @@ const en = (key: string) => studioString(key, 'en')!;
 
 describe('AddFieldPopover — strings from the studio namespace (objectstack#25922)', () => {
   it('zh: English while the catalogue is in flight, then Chinese on the same mount', async () => {
-    // The premise: these keys are the namespace's, and the title is the table's.
-    for (const key of MOVED) expect(en(key), key).toBeDefined();
-    expect(studioString(TABLE, 'en')).toBeUndefined();
+    // The premise: every one of these keys is the namespace's.
+    for (const key of [...MOVED, CHROME]) expect(en(key), key).toBeDefined();
     expect(isStudioCatalogueLoaded('zh-CN')).toBe(false);
 
     render(<Screen lang="zh" />);
@@ -77,14 +79,14 @@ describe('AddFieldPopover — strings from the studio namespace (objectstack#259
     for (const key of MOVED) expect(zh[key], key).not.toBe(en(key));
     expect(await screen.findByText(zh['designer.field.label'])).toBeInTheDocument();
     for (const key of MOVED) expect(popover()).toHaveTextContent(zh[key]);
-    expect(popover()).toHaveTextContent(t(TABLE, 'zh-CN'));
-    expect(t(TABLE, 'zh-CN')).not.toBe(t(TABLE, 'en-US'));
+    expect(popover()).toHaveTextContent(t(CHROME, 'zh-CN'));
+    expect(t(CHROME, 'zh-CN')).not.toBe(t(CHROME, 'en-US'));
   });
 
-  it('de: a third locale renders English from both homes', () => {
+  it('de: a third locale renders English through both doors', () => {
     render(<Screen lang="de" />);
     for (const key of MOVED) expect(popover()).toHaveTextContent(en(key));
-    expect(popover()).toHaveTextContent(t(TABLE, 'en-US'));
+    expect(popover()).toHaveTextContent(t(CHROME, 'en-US'));
     for (const key of MOVED) expect(t(key, 'de')).toBe(en(key));
   });
 });