fix: keep conversation history visible

tests/dashboard/conversations.test.tsx

@@ -7,7 +7,7 @@ import userEvent from '@testing-library/user-event';
 import { HttpResponse, http } from 'msw';
 import { setupServer } from 'msw/node';
 import { MemoryRouter } from 'react-router-dom';
-import { afterAll, afterEach, beforeAll, describe, expect, it } from 'vitest';
+import { afterAll, afterEach, beforeAll, describe, expect, it, vi } from 'vitest';
 import { ConversationsPage } from '../../apps/dashboard/src/features/conversations/conversations-page.js';
 import { resetComposerDrafts } from '../../apps/dashboard/src/features/conversations/composer-drafts.js';
 
@@ -83,6 +83,7 @@ const server = setupServer(
   http.post('/api/conversations/bulk-read', () =>
     HttpResponse.json({ success: true, updated: 1, failed: [] })),
 );
+const originalScrollIntoView = Object.getOwnPropertyDescriptor(HTMLElement.prototype, 'scrollIntoView');
 
 function installConversationList() {
   server.use(
@@ -110,6 +111,8 @@ afterEach(() => {
   cleanup();
   server.resetHandlers();
   resetComposerDrafts();
+  if (originalScrollIntoView) Object.defineProperty(HTMLElement.prototype, 'scrollIntoView', originalScrollIntoView);
+  else delete HTMLElement.prototype.scrollIntoView;
 });
 afterAll(() => server.close());
 
@@ -495,6 +498,11 @@ describe('ConversationsPage', () => {
       }),
     );
     const user = userEvent.setup();
+    const scrollIntoView = vi.fn();
+    Object.defineProperty(HTMLElement.prototype, 'scrollIntoView', {
+      configurable: true,
+      value: scrollIntoView,
+    });
     renderConversations();
 
     await user.click(await screen.findByRole('button', { name: /u\/alice/ }));
@@ -502,6 +510,7 @@ describe('ConversationsPage', () => {
     expect(await screen.findByRole('img', { name: 'Green-screen source green-phone.jpg' })).toHaveClass('is-blurred');
     await user.click(screen.getByRole('button', { name: 'Reveal source images' }));
     await user.click(screen.getByRole('radio', { name: /green-phone\.jpg/ }));
+    await waitFor(() => expect(scrollIntoView).toHaveBeenCalledWith({ behavior: 'smooth', block: 'nearest' }));
     await user.click(screen.getByRole('button', { name: 'Reveal conversation choices' }));
     await user.click(screen.getByRole('radio', { name: 'Original post image' }));
     await user.click(screen.getByRole('button', { name: 'Create image' }));