fix(desktop): unify shell dialogs and recovery screens with emcn

.github/workflows/desktop-e2e.yml

@@ -10,7 +10,11 @@ on:
       - '.github/workflows/desktop-e2e.yml'
       - '.github/workflows/desktop-release.yml'
       - 'apps/desktop/**'
+      - 'apps/sim/app/_styles/**'
+      - 'apps/sim/lib/postcss/**'
+      - 'apps/sim/postcss.config.mjs'
       - 'apps/sim/public/brand/fonts/**'
+      - 'packages/emcn/**'
       - 'packages/desktop-bridge/**'
       - 'packages/browser-protocol/**'
       - 'packages/terminal-protocol/**'

apps/desktop/e2e/packaged-smoke.spec.ts

@@ -146,8 +146,8 @@ test('packaged shell renders the bundled offline page', async () => {
       .toBe(true)
     const picker = findPage('sim-shell://pages/server.html')
     if (!picker) throw new Error('server picker disappeared')
-    await expect(picker.locator('h1')).toHaveText('Sim server')
-    await expect(picker.locator('#origin')).toHaveValue('http://127.0.0.1:1')
+    await expect(picker.getByRole('dialog', { name: 'Sim server' })).toBeVisible()
+    await expect(picker.getByLabel('Server URL')).toHaveValue('http://127.0.0.1:1')
   } finally {
     await browser?.close().catch(() => {})
     if (child.exitCode === null && child.signalCode === null) {

apps/desktop/e2e/smoke.spec.ts

@@ -158,8 +158,11 @@ test.describe('desktop shell smoke', () => {
     const window = await app.firstWindow()
     await window.waitForSelector('#retry', { timeout: 30_000 })
     expect(window.url()).toMatch(/^sim-shell:\/\/pages\/offline\.html\?/)
-    await expect(window.locator('.wordmark')).toBeVisible()
-    await expect(window.locator('.wordmark')).toHaveAttribute('aria-label', 'Sim')
+    await expect(window.getByRole('img', { name: 'Sim', exact: true })).toBeVisible()
+    await expect(window.getByRole('img', { name: 'Sim', exact: true })).toHaveAttribute(
+      'aria-label',
+      'Sim'
+    )
     await expect(window.locator('#title')).toHaveText('Can’t connect to Sim')
     // The recovery path for a self-hosted shell pointed at a server it cannot
     // reach. Exercised end to end here because it is the only coverage of the
@@ -173,22 +176,74 @@ test.describe('desktop shell smoke', () => {
     await expect
       .poll(() => window.evaluate(() => document.fonts.check('16px "Season Sans"')))
       .toBe(true)
-    await expect(window.locator('#retry')).toHaveCSS('height', '30px')
-    await expect(window.locator('#retry')).toHaveCSS('border-radius', '8px')
-    await expect(window.locator('#retry')).toHaveCSS('padding-left', '8px')
-    await expect(window.locator('#retry')).toHaveCSS('font-size', '14px')
-    await expect(window.locator('#retry')).toHaveCSS('line-height', '20px')
-    await expect(window.locator('#retry')).toHaveCSS('text-align', 'left')
-    await window.locator('#retry').focus()
-    await expect(window.locator('#retry')).toHaveCSS('outline-style', 'solid')
     await expect(window.locator('#detail')).toHaveAttribute('role', 'status')
   })
 
+  test('recovery messages use an isolated EMCN dialog with a safe keyboard default', async () => {
+    app = await launchApp('http://127.0.0.1:1')
+    const window = await app.firstWindow()
+    await expect(window.locator('#server')).toBeVisible()
+    const dialogPromise = app.waitForEvent('window')
+    await app.evaluate(({ BrowserWindow }) => {
+      BrowserWindow.getAllWindows()[0].webContents.emit('unresponsive')
+    })
+    const prompt = await dialogPromise
+    await expect(prompt.getByRole('dialog', { name: 'Sim', exact: true })).toBeVisible()
+    await expect(prompt.getByText('Sim isn’t responding')).toBeVisible()
+    await expect(prompt.getByRole('button', { name: 'Wait', exact: true })).toBeFocused()
+    await expect
+      .poll(() =>
+        prompt
+          .getByRole('dialog')
+          .evaluate((element) => element.scrollHeight <= globalThis.innerHeight)
+      )
+      .toBe(true)
+    await expect
+      .poll(() => prompt.evaluate(() => typeof (globalThis as { simDesktop?: unknown }).simDesktop))
+      .toBe('undefined')
+    await prompt.screenshot({
+      path: test.info().outputPath('recovery-dialog.png'),
+      animations: 'disabled',
+    })
+    await app.evaluate(({ BrowserWindow }) => {
+      const win = BrowserWindow.getAllWindows().find(
+        (entry) => entry.webContents.getURL() === 'sim-shell://pages/dialog.html'
+      )
+      if (!win) throw new Error('Recovery dialog is missing')
+      win.webContents.ipc.removeHandler('shell:configuration')
+      win.webContents.ipc.handle('shell:configuration', () => ({
+        title: 'Long recovery message',
+        message: 'Recovery details',
+        detail: Array.from({ length: 80 }, (_, index) => `Diagnostic detail ${index + 1}`).join(
+          '\n'
+        ),
+        type: 'warning',
+        buttons: ['Wait', 'Reload'],
+        defaultId: 0,
+        cancelId: 0,
+      }))
+      win.webContents.reload()
+    })
+    await expect(
+      prompt.getByRole('dialog', { name: 'Long recovery message', exact: true })
+    ).toBeVisible()
+    await expect(prompt.getByRole('button', { name: 'Reload', exact: true })).toBeInViewport()
+    await expect(prompt.getByRole('button', { name: 'Wait', exact: true })).toBeFocused()
+    const closed = prompt.waitForEvent('close')
+    await prompt
+      .getByRole('button', { name: 'Wait', exact: true })
+      .press('Enter')
+      .catch(() => {})
+    await closed
+    await expect(window.locator('#server')).toBeVisible()
+  })
+
   // The picker is the only way to repoint a shell whose server is unreachable.
   // Its page, the pre-filled value (which crosses the local-page IPC gate) and
   // Escape are asserted together because the packaged build once opened it as
   // a blank sheet with no way out.
-  test('the offline page opens the server picker, pre-filled, and Escape closes it', async () => {
+  test('the offline server picker renders EMCN controls and handles validation and dismissal', async () => {
+    const testInfo = test.info()
     app = await launchApp('http://127.0.0.1:1')
     const window = await app.firstWindow()
     await window.waitForSelector('#server', { timeout: 30_000 })
@@ -198,8 +253,42 @@ test.describe('desktop shell smoke', () => {
     const picker = await pickerPromise
 
     expect(picker.url()).toBe('sim-shell://pages/server.html')
-    await expect(picker.locator('h1')).toHaveText('Sim server')
-    await expect(picker.locator('#origin')).toHaveValue('http://127.0.0.1:1')
+    await expect(picker.getByRole('dialog', { name: 'Sim server', exact: true })).toBeVisible()
+    await expect(picker.getByLabel('Server URL')).toHaveValue('http://127.0.0.1:1')
+    await expect(picker.getByLabel('Server URL')).toBeFocused()
+    await expect
+      .poll(() =>
+        picker
+          .getByRole('dialog')
+          .evaluate((element) => element.scrollHeight <= globalThis.innerHeight)
+      )
+      .toBe(true)
+    await picker.getByLabel('Server URL').fill('http://example.com')
+    await picker.getByLabel('Server URL').press('Enter')
+    await expect(picker.getByRole('alert')).toBeVisible()
+    await expect(picker.getByLabel('Server URL')).toHaveAttribute('aria-invalid', 'true')
+    await picker.getByLabel('Server URL').fill('http://127.0.0.1:1')
+    await expect(picker.getByRole('alert')).toHaveCount(0)
+    await picker.getByRole('button', { name: 'Connect', exact: true }).click()
+    await expect(picker.getByRole('status')).toHaveText('Already connected to this server.')
+    await expect
+      .poll(() =>
+        picker
+          .locator('[data-chip-modal-body]')
+          .evaluate((element) => element.scrollHeight <= element.clientHeight)
+      )
+      .toBe(true)
+    await picker.emulateMedia({ colorScheme: 'light' })
+    await picker.screenshot({
+      path: testInfo.outputPath('server-modal-light.png'),
+      animations: 'disabled',
+    })
+    await picker.emulateMedia({ colorScheme: 'dark' })
+    await expect(picker.locator('html')).toHaveClass('dark')
+    await picker.screenshot({
+      path: testInfo.outputPath('server-modal-dark.png'),
+      animations: 'disabled',
+    })
 
     const closed = picker.waitForEvent('close')
     // The main process destroys the window on the key-down, so the key-up half

apps/desktop/package.json

@@ -3,7 +3,7 @@
   "version": "0.0.0",
   "private": true,
   "license": "Apache-2.0",
-  "description": "Sim desktop app for macOS — Electron shell around the hosted web app",
+  "description": "Sim desktop app for macOS \u2014 Electron shell around the hosted web app",
   "author": "Sim <support@sim.ai>",
   "homepage": "https://sim.ai",
   "type": "module",
@@ -47,13 +47,20 @@
   "devDependencies": {
     "@electron/fuses": "1.8.0",
     "@playwright/test": "1.61.1",
+    "@sim/emcn": "workspace:*",
     "@sim/tsconfig": "workspace:*",
     "@types/micromatch": "4.0.10",
     "@types/node": "24.2.1",
+    "@types/react": "^19",
+    "@types/react-dom": "^19",
     "electron": "43.5.0",
     "electron-builder": "26.15.3",
     "esbuild": "0.28.1",
     "jsdom": "^26.0.0",
+    "postcss": "^8",
+    "postcss-load-config": "6.0.1",
+    "react": "19.2.4",
+    "react-dom": "19.2.4",
     "typescript": "^7.0.2",
     "vitest": "^4.1.0"
   }

apps/desktop/scripts/build.ts

@@ -1,7 +1,9 @@
 import { execFileSync } from 'node:child_process'
-import { cpSync, existsSync, mkdirSync, rmSync } from 'node:fs'
-import { dirname, join } from 'node:path'
-import { build } from 'esbuild'
+import { cpSync, existsSync, mkdirSync, readFileSync, rmSync } from 'node:fs'
+import { dirname, join, resolve } from 'node:path'
+import { type BuildOptions, build } from 'esbuild'
+import postcss from 'postcss'
+import loadPostcssConfig from 'postcss-load-config'
 import { identityForOrigin } from './channels'
 
 const watch = process.argv.includes('--watch')
@@ -94,10 +96,56 @@ const common = {
   },
 }
 
+/** Bundles the shared EMCN components and app tokens for offline shell use. */
+const renderer: BuildOptions = {
+  entryPoints: {
+    server: 'src/renderer/server/index.tsx',
+    offline: 'src/renderer/offline/index.tsx',
+    dialog: 'src/renderer/dialog/index.tsx',
+  },
+  outdir: 'dist/renderer',
+  bundle: true,
+  platform: 'browser',
+  format: 'iife',
+  target: 'chrome146',
+  minify: true,
+  tsconfig: 'tsconfig.json',
+  external: ['*.woff2'],
+  define: { 'process.env.NODE_ENV': '"production"', 'process.env': '{}' },
+  loader: { '.module.css': 'local-css' },
+  plugins: [
+    {
+      name: 'desktop-tailwind',
+      setup(builder) {
+        builder.onLoad({ filter: /shell\.css$/ }, async ({ path }) => {
+          const config = await loadPostcssConfig({}, resolve('../sim'))
+          const result = await postcss(config.plugins).process(readFileSync(path, 'utf8'), {
+            from: path,
+          })
+          return {
+            contents: result.css,
+            loader: 'css',
+            resolveDir: dirname(path),
+            watchFiles: result.messages.flatMap((message) =>
+              message.type === 'dependency' ? [message.file as string] : []
+            ),
+          }
+        })
+      },
+    },
+  ],
+}
+
 async function run(): Promise<void> {
   compileNativeHelpSearch()
   if (watch) {
     const { context } = await import('esbuild')
+    const rendererCtx = await context(renderer)
+    const shellPreloadCtx = await context({
+      ...common,
+      entryPoints: ['src/preload/shell.ts'],
+      outfile: 'dist/shell-preload.cjs',
+    })
     const mainCtx = await context({
       ...common,
       entryPoints: ['src/main/index.ts'],
@@ -115,10 +163,18 @@ async function run(): Promise<void> {
       entryPoints: ['src/preload/browser/index.ts'],
       outfile: 'dist/browser-preload.cjs',
     })
-    await Promise.all([mainCtx.watch(), preloadCtx.watch(), browserPreloadCtx.watch()])
+    await Promise.all([
+      mainCtx.watch(),
+      preloadCtx.watch(),
+      browserPreloadCtx.watch(),
+      rendererCtx.watch(),
+      shellPreloadCtx.watch(),
+    ])
     return
   }
   await Promise.all([
+    build(renderer),
+    build({ ...common, entryPoints: ['src/preload/shell.ts'], outfile: 'dist/shell-preload.cjs' }),
     build({ ...common, entryPoints: ['src/main/index.ts'], outfile: 'dist/main.cjs' }),
     build({ ...common, entryPoints: ['src/preload/index.ts'], outfile: 'dist/preload.cjs' }),
     build({

apps/desktop/src/main/browser-agent/session.ts

@@ -36,7 +36,6 @@ import type {
 } from 'electron'
 import {
   app,
-  dialog,
   session as electronSession,
   Menu,
   nativeTheme,
@@ -71,6 +70,7 @@ import {
 } from '@/main/browser-agent/url-guard'
 import { browserUserAgent } from '@/main/browser-agent/user-agent'
 import type { BrowserSessionSnapshot } from '@/main/desktop-chat-session-store'
+import { showShellDialog } from '@/main/dialogs'
 import { suggestedFilename, uniqueDownloadPath } from '@/main/downloads'
 import {
   type FocusedResourceShortcut,
@@ -1524,17 +1524,16 @@ async function requestSitePermission(details: {
     const pending = scoped.tab.pendingSitePermission
     if (!pending || pending.request.requestId !== request.requestId) return await allowed
     pending.nativePromptController = nativePromptController
-    void dialog
-      .showMessageBox(win, {
-        type: 'warning',
-        buttons: ['Block', 'Allow'],
-        defaultId: 0,
-        cancelId: 0,
-        noLink: true,
-        signal: nativePromptController.signal,
-        message: `Allow this browser task to open ${request.origin}?`,
-        detail: 'Only allow this site if it is expected for the current task.',
-      })
+    void showShellDialog(win, {
+      type: 'warning',
+      buttons: ['Block', 'Allow'],
+      defaultId: 0,
+      cancelId: 0,
+      noLink: true,
+      signal: nativePromptController.signal,
+      message: `Allow this browser task to open ${request.origin}?`,
+      detail: 'Only allow this site if it is expected for the current task.',
+    })
       .then(({ response }) => {
         withBrowserScope(scoped.scopeId, () => {
           respondToSitePermission(request.requestId, response === 1)

apps/desktop/src/main/browser-credentials/os-auth.ts

@@ -1,6 +1,7 @@
 import { createLogger } from '@sim/logger'
 import type { MessageBoxOptions } from 'electron'
-import { BrowserWindow, dialog, systemPreferences } from 'electron'
+import { BrowserWindow, systemPreferences } from 'electron'
+import { showShellDialog } from '@/main/dialogs'
 
 const logger = createLogger('BrowserCredentialAuth')
 
@@ -143,8 +144,8 @@ async function promptForSecret(reason: string, action: string): Promise<boolean>
     const parent = BrowserWindow.getFocusedWindow()
     const { response } =
       parent && !parent.isDestroyed()
-        ? await dialog.showMessageBox(parent, options)
-        : await dialog.showMessageBox(options)
+        ? await showShellDialog(parent, options)
+        : await showShellDialog(options)
     return response === 1
   } catch (error) {
     // Fail closed: if the confirmation cannot be shown, nothing is revealed.