perf: reduce re-renders, fix mobile keyboard handling, add chunk load recovery, and improve PATH management (#1028)

* fix: exclude file content from reverted prompt text

Revert and fork now restore only the user's original prompt, not server-injected file content
Uses existing isSyntheticPart helper for type-safe filtering

* fix: keep scrollbar visible when hovering over thumb

* fix: prevent ESC abort from triggering when terminal is focused

* fix: pass directory to permission/question reply calls so approvals actually resolve

* fix: default model selection not responding after Base UI migration

* fix: prevent modal content from shifting and clipping footer buttons

* fix: improve session switching performance and add sub-agent export with prompt collapse

Defer viewport anchor saving to eliminate ~800ms UI freeze when switching sessions
Add export dialog to include sub-agent tasks recursively in markdown export
Add collapse chevron button for expanded user prompts in sticky header

* fix: resolve sidebar scroll and TDZ crash in session sidebar

* perf: reduce CPU overhead and re-renders across chat, layout, and settings

* fix: position collapse button at top of message and prevent ESC abort in terminal

* fix: position collapse button at top and add padding only when expanded

* refactor: extract shared PATH utilities and mobile keyboard hook

* refactor: import shared path-utils in electron, use module-level style constants

- Electron now imports pathLooksUserConfigured/mergePathValues from
  shared path-utils.js instead of inline duplication
- ToolPart collapsedCustomStyle moved from useMemo([]) to module const

* fix: resolve remaining merge conflicts and type errors

- Remove duplicate variable declarations in SessionNodeItem
- Remove orphaned export callback body from conflict resolution
- Fix HelpDialog description -> descriptionKey (i18n rename)

* fix: resolve type-check and lint errors in session-actions.test.ts

- Added missing bun:test type declarations (beforeEach, mock, mock.module)
- Removed unused State import
- Replaced 'as any' casts with proper OpencodeClient and ChildStoreManager types
- Added eslint-disable for unused _ parameter in mock function

* fix PR 1028 export and PATH edge cases

* fix startup retry exhaustion state

* remove opencode package lock change

* fix sub-session rename cancellation

---------

Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/lib/desktopBoot.test.ts

@@ -69,7 +69,7 @@ describe('resolveDesktopBootView', () => {
         isDesktopShell: true,
         bootOutcome: { target: 'local', status: 'unreachable' },
       }),
-    ).toEqual({ screen: 'recovery', variant: 'local-unreachable' });
+    ).toEqual({ screen: 'recovery', variant: 'local-unavailable' });
   });
 
   test('returns recovery view for remote missing', () => {
@@ -257,9 +257,9 @@ describe('getInjectedBootOutcome', () => {
 
   test('returns valid outcome for well-formed main-local', () => {
     const w = mockWindow();
-    w.__OPENCHAMBER_DESKTOP_BOOT_OUTCOME__ = { kind: 'main-local' };
+    w.__OPENCHAMBER_DESKTOP_BOOT_OUTCOME__ = { target: 'local', status: 'ok' };
     try {
-      expect(getInjectedBootOutcome()).toEqual({ kind: 'main-local' });
+      expect(getInjectedBootOutcome()).toEqual({ target: 'local', status: 'ok' });
     } finally {
       restoreWindow();
     }
@@ -339,7 +339,7 @@ describe('getBootInjectionStatus', () => {
 
   test('returns "valid" when global is present and well-formed', () => {
     const w = mockWindow();
-    w.__OPENCHAMBER_DESKTOP_BOOT_OUTCOME__ = { kind: 'main-local' };
+    w.__OPENCHAMBER_DESKTOP_BOOT_OUTCOME__ = { target: 'local', status: 'ok' };
     try {
       expect(getBootInjectionStatus()).toBe('valid');
     } finally {

packages/ui/src/lib/exportSession.ts

@@ -5,6 +5,13 @@ import { getRevealLabelKey } from '@/lib/utils';
 
 type SessionMessageRecord = { info: Message; parts: Part[] };
 
+export type ChildSessionExport = {
+  title: string;
+  agent?: string;
+  records: SessionMessageRecord[];
+  children: ChildSessionExport[];
+};
+
 function formatTimestamp(timestamp: number | undefined): string {
   if (typeof timestamp !== 'number' || !Number.isFinite(timestamp)) {
     return '';
@@ -65,9 +72,29 @@ function formatMessageAsMarkdown(record: SessionMessageRecord): string {
   return `${role}\n\n${text}`;
 }
 
+function formatChildSessionAsMarkdown(child: ChildSessionExport, depth: number): string {
+  const heading = '#'.repeat(Math.min(depth + 1, 6));
+  const agentLabel = child.agent ? ` — ${child.agent}` : '';
+  const childHeader = `${heading} Sub-agent: ${child.title}${agentLabel}\n\n---\n\n`;
+
+  const childBody = child.records
+    .map(formatMessageAsMarkdown)
+    .filter(Boolean)
+    .join('\n\n---\n\n');
+
+  const parts = [childHeader + childBody];
+
+  for (const grandchild of child.children) {
+    parts.push(formatChildSessionAsMarkdown(grandchild, depth + 1));
+  }
+
+  return parts.join('\n\n---\n\n');
+}
+
 export function formatSessionAsMarkdown(
   messages: SessionMessageRecord[],
   sessionTitle?: string | null,
+  childSessions?: ChildSessionExport[],
 ): string {
   const title = sessionTitle?.trim() || 'Session';
   const date = new Date().toISOString().split('T')[0];
@@ -79,7 +106,16 @@ export function formatSessionAsMarkdown(
     .filter(Boolean)
     .join('\n\n---\n\n');
 
-  return header + body;
+  let result = header + body;
+
+  if (childSessions && childSessions.length > 0) {
+    const childMarkdown = childSessions
+      .map((child) => formatChildSessionAsMarkdown(child, 1))
+      .join('\n\n---\n\n');
+    result += '\n\n---\n\n' + childMarkdown;
+  }
+
+  return result;
 }
 
 export function downloadAsMarkdown(content: string, filename: string): void {

packages/ui/src/lib/i18n/messages/en.ts

@@ -236,6 +236,14 @@ export const dict = {
   'sessions.sidebar.session.export.nothingToExport': 'Nothing to export',
   'sessions.sidebar.session.export.success': 'Session exported',
   'sessions.sidebar.session.export.failedRevealPath': 'Failed to reveal path',
+  'sessions.sidebar.session.export.untitledSubagent': 'Untitled Sub-agent',
+  'sessions.sidebar.session.export.skippedSubtaskSingle': 'Exported session, but skipped {count} sub-agent task that could not be loaded.',
+  'sessions.sidebar.session.export.skippedSubtaskMany': 'Exported session, but skipped {count} sub-agent tasks that could not be loaded.',
+  'sessions.sidebar.session.export.dialog.title': 'Export Markdown',
+  'sessions.sidebar.session.export.dialog.descriptionSingle': 'This session has {count} sub-agent task. Include it in the export?',
+  'sessions.sidebar.session.export.dialog.descriptionMany': 'This session has {count} sub-agent tasks. Include them in the export?',
+  'sessions.sidebar.session.export.dialog.includeSubtasks': 'Include sub-agent tasks',
+  'sessions.sidebar.session.export.dialog.confirm': 'Export',
   'sessions.sidebar.session.status.active': 'Session active',
   'sessions.sidebar.session.status.unread': 'Unread updates',
   'sessions.sidebar.session.status.pinned': 'Pinned session',
@@ -1958,6 +1966,10 @@ export const dict = {
   'onboarding.desktopRecovery.common.useRemote': 'Use Remote',
   'onboarding.desktopRecovery.actions.retrying': 'Retrying…',
   'onboarding.desktopRecovery.actions.retryConnection': 'Retry Connection',
+  'startup.initRecovery.title': 'Startup failed',
+  'startup.initRecovery.description': 'OpenChamber could not finish initialization. Check that the server is running, then retry.',
+  'startup.initRecovery.retry': 'Retry',
+  'startup.initRecovery.retrying': 'Retrying…',
   'onboarding.desktopRecovery.placeholders.remoteServer': 'the remote server',
   'onboarding.desktopRecovery.placeholders.unknownServer': 'unknown',
   'vscodeLayout.title.chat': 'Chat',

packages/ui/src/lib/i18n/messages/es.ts

@@ -237,6 +237,14 @@ export const dict: Record<I18nKey, string> = {
   "sessions.sidebar.session.export.nothingToExport": "No hay nada para exportar",
   "sessions.sidebar.session.export.success": "Sesión exportada",
   "sessions.sidebar.session.export.failedRevealPath": "No se pudo mostrar la ruta",
+  "sessions.sidebar.session.export.untitledSubagent": "Subagente sin título",
+  "sessions.sidebar.session.export.skippedSubtaskSingle": "La sesión se exportó, pero se omitió {count} tarea de subagente que no se pudo cargar.",
+  "sessions.sidebar.session.export.skippedSubtaskMany": "La sesión se exportó, pero se omitieron {count} tareas de subagente que no se pudieron cargar.",
+  "sessions.sidebar.session.export.dialog.title": "Exportar Markdown",
+  "sessions.sidebar.session.export.dialog.descriptionSingle": "Esta sesión tiene {count} tarea de subagente. ¿Incluirla en la exportación?",
+  "sessions.sidebar.session.export.dialog.descriptionMany": "Esta sesión tiene {count} tareas de subagente. ¿Incluirlas en la exportación?",
+  "sessions.sidebar.session.export.dialog.includeSubtasks": "Incluir tareas de subagente",
+  "sessions.sidebar.session.export.dialog.confirm": "Exportar",
   "sessions.sidebar.session.status.active": "Sesión activa",
   "sessions.sidebar.session.status.unread": "Actualizaciones no leídas",
   "sessions.sidebar.session.status.pinned": "Sesión anclada",
@@ -1959,6 +1967,10 @@ export const dict: Record<I18nKey, string> = {
   "onboarding.desktopRecovery.common.useRemote": "Usar remoto",
   "onboarding.desktopRecovery.actions.retrying": "Reintentando…",
   "onboarding.desktopRecovery.actions.retryConnection": "Reintentar conexión",
+  "startup.initRecovery.title": "Error al iniciar",
+  "startup.initRecovery.description": "OpenChamber no pudo completar la inicialización. Comprueba que el servidor esté en ejecución y vuelve a intentarlo.",
+  "startup.initRecovery.retry": "Reintentar",
+  "startup.initRecovery.retrying": "Reintentando…",
   "onboarding.desktopRecovery.placeholders.remoteServer": "el servidor remoto",
   "onboarding.desktopRecovery.placeholders.unknownServer": "desconocido",
   "vscodeLayout.title.chat": "Chat",

packages/ui/src/lib/i18n/messages/pt-BR.ts

@@ -237,6 +237,14 @@ export const dict: Record<I18nKey, string> = {
   "sessions.sidebar.session.export.nothingToExport": "Não há nada para exportar",
   "sessions.sidebar.session.export.success": "Sessão exportada",
   "sessions.sidebar.session.export.failedRevealPath": "Não foi possível mostrar o caminho",
+  "sessions.sidebar.session.export.untitledSubagent": "Subagente sem título",
+  "sessions.sidebar.session.export.skippedSubtaskSingle": "A sessão foi exportada, mas {count} tarefa de subagente não pôde ser carregada e foi ignorada.",
+  "sessions.sidebar.session.export.skippedSubtaskMany": "A sessão foi exportada, mas {count} tarefas de subagente não puderam ser carregadas e foram ignoradas.",
+  "sessions.sidebar.session.export.dialog.title": "Exportar Markdown",
+  "sessions.sidebar.session.export.dialog.descriptionSingle": "Esta sessão tem {count} tarefa de subagente. Incluí-la na exportação?",
+  "sessions.sidebar.session.export.dialog.descriptionMany": "Esta sessão tem {count} tarefas de subagente. Incluí-las na exportação?",
+  "sessions.sidebar.session.export.dialog.includeSubtasks": "Incluir tarefas de subagente",
+  "sessions.sidebar.session.export.dialog.confirm": "Exportar",
   "sessions.sidebar.session.status.active": "Sessão ativa",
   "sessions.sidebar.session.status.unread": "Atualizações não lidas",
   "sessions.sidebar.session.status.pinned": "Sessão fixada",
@@ -1959,6 +1967,10 @@ export const dict: Record<I18nKey, string> = {
   "onboarding.desktopRecovery.common.useRemote": "Usar remoto",
   "onboarding.desktopRecovery.actions.retrying": "Retentendo…",
   "onboarding.desktopRecovery.actions.retryConnection": "Tentar novamente conexão",
+  "startup.initRecovery.title": "Falha ao iniciar",
+  "startup.initRecovery.description": "O OpenChamber não conseguiu concluir a inicialização. Verifique se o servidor está em execução e tente novamente.",
+  "startup.initRecovery.retry": "Tentar novamente",
+  "startup.initRecovery.retrying": "Tentando novamente…",
   "onboarding.desktopRecovery.placeholders.remoteServer": "o servidor remoto",
   "onboarding.desktopRecovery.placeholders.unknownServer": "desconhecido",
   "vscodeLayout.title.chat": "Chat",

packages/ui/src/lib/i18n/messages/uk.ts

@@ -237,6 +237,14 @@ export const dict: Record<I18nKey, string> = {
   "sessions.sidebar.session.export.nothingToExport": "Нічого для експорту",
   "sessions.sidebar.session.export.success": "Сесія експортовано",
   "sessions.sidebar.session.export.failedRevealPath": "Не вдалося відкрити шлях",
+  "sessions.sidebar.session.export.untitledSubagent": "Під-агент без назви",
+  "sessions.sidebar.session.export.skippedSubtaskSingle": "Сесію експортовано, але пропущено {count} завдання під-агента, яке не вдалося завантажити.",
+  "sessions.sidebar.session.export.skippedSubtaskMany": "Сесію експортовано, але пропущено {count} завдань під-агента, які не вдалося завантажити.",
+  "sessions.sidebar.session.export.dialog.title": "Експорт Markdown",
+  "sessions.sidebar.session.export.dialog.descriptionSingle": "Ця сесія має {count} завдання під-агента. Додати його до експорту?",
+  "sessions.sidebar.session.export.dialog.descriptionMany": "Ця сесія має {count} завдань під-агентів. Додати їх до експорту?",
+  "sessions.sidebar.session.export.dialog.includeSubtasks": "Додати завдання під-агентів",
+  "sessions.sidebar.session.export.dialog.confirm": "Експортувати",
   "sessions.sidebar.session.status.active": "Сесія активний",
   "sessions.sidebar.session.status.unread": "Непрочитані оновлення",
   "sessions.sidebar.session.status.pinned": "Закріплений сесія",
@@ -1959,6 +1967,10 @@ export const dict: Record<I18nKey, string> = {
   "onboarding.desktopRecovery.common.useRemote": "Використовувати Remote",
   "onboarding.desktopRecovery.actions.retrying": "Повторна спроба…",
   "onboarding.desktopRecovery.actions.retryConnection": "Повторити підключення",
+  "startup.initRecovery.title": "Не вдалося запустити",
+  "startup.initRecovery.description": "OpenChamber не зміг завершити ініціалізацію. Перевірте, що сервер запущений, і повторіть спробу.",
+  "startup.initRecovery.retry": "Повторити спробу",
+  "startup.initRecovery.retrying": "Повторна спроба…",
   "onboarding.desktopRecovery.placeholders.remoteServer": "віддалений сервер",
   "onboarding.desktopRecovery.placeholders.unknownServer": "невідомий",
   "vscodeLayout.title.chat": "Чат",

packages/ui/src/lib/i18n/messages/zh-CN.ts

@@ -237,6 +237,14 @@ export const dict: Record<I18nKey, string> = {
   'sessions.sidebar.session.export.nothingToExport': '没有可导出的内容',
   'sessions.sidebar.session.export.success': '会话已导出',
   'sessions.sidebar.session.export.failedRevealPath': '显示路径失败',
+  'sessions.sidebar.session.export.untitledSubagent': '未命名子代理',
+  'sessions.sidebar.session.export.skippedSubtaskSingle': '会话已导出，但跳过了 {count} 个无法加载的子代理任务。',
+  'sessions.sidebar.session.export.skippedSubtaskMany': '会话已导出，但跳过了 {count} 个无法加载的子代理任务。',
+  'sessions.sidebar.session.export.dialog.title': '导出 Markdown',
+  'sessions.sidebar.session.export.dialog.descriptionSingle': '此会话有 {count} 个子代理任务。是否包含在导出中？',
+  'sessions.sidebar.session.export.dialog.descriptionMany': '此会话有 {count} 个子代理任务。是否包含在导出中？',
+  'sessions.sidebar.session.export.dialog.includeSubtasks': '包含子代理任务',
+  'sessions.sidebar.session.export.dialog.confirm': '导出',
   'sessions.sidebar.session.status.active': '会话活跃中',
   'sessions.sidebar.session.status.unread': '有未读更新',
   'sessions.sidebar.session.status.pinned': '已置顶会话',
@@ -1959,6 +1967,10 @@ export const dict: Record<I18nKey, string> = {
   'onboarding.desktopRecovery.common.useRemote': '使用远程',
   'onboarding.desktopRecovery.actions.retrying': '重试中…',
   'onboarding.desktopRecovery.actions.retryConnection': '重试连接',
+  'startup.initRecovery.title': '启动失败',
+  'startup.initRecovery.description': 'OpenChamber 未能完成初始化。请检查服务器是否正在运行，然后重试。',
+  'startup.initRecovery.retry': '重试',
+  'startup.initRecovery.retrying': '重试中…',
   'onboarding.desktopRecovery.placeholders.remoteServer': '远程服务器',
   'onboarding.desktopRecovery.placeholders.unknownServer': '未知服务器',
   'vscodeLayout.title.chat': '聊天',

packages/ui/src/lib/messages/synthetic.test.ts

@@ -0,0 +1,123 @@
+import { describe, expect, test } from "bun:test"
+import type { Part } from "@opencode-ai/sdk/v2"
+import { isSyntheticPart, isFullySyntheticMessage, filterSyntheticParts } from "./synthetic"
+
+function createTextPart(id: string, text: string, synthetic?: boolean): Part {
+  return {
+    id,
+    sessionID: "session-1",
+    messageID: "message-1",
+    type: "text",
+    text,
+    ...(synthetic !== undefined ? { synthetic } : {}),
+  } as Part
+}
+
+function createFilePart(id: string, url: string): Part {
+  return {
+    id,
+    sessionID: "session-1",
+    messageID: "message-1",
+    type: "file",
+    mime: "text/plain",
+    url,
+  } as Part
+}
+
+describe("isSyntheticPart", () => {
+  test("returns false for undefined", () => {
+    expect(isSyntheticPart(undefined)).toBe(false)
+  })
+
+  test("returns false for non-object", () => {
+    expect(isSyntheticPart(null as unknown as Part)).toBe(false)
+    expect(isSyntheticPart("string" as unknown as Part)).toBe(false)
+  })
+
+  test("returns false for parts without synthetic property", () => {
+    const part = createTextPart("1", "hello")
+    expect(isSyntheticPart(part)).toBe(false)
+  })
+
+  test("returns false for parts with synthetic: false", () => {
+    const part = createTextPart("1", "hello", false)
+    expect(isSyntheticPart(part)).toBe(false)
+  })
+
+  test("returns true for parts with synthetic: true", () => {
+    const part = createTextPart("1", "file content here", true)
+    expect(isSyntheticPart(part)).toBe(true)
+  })
+
+  test("returns false for file parts", () => {
+    const part = createFilePart("1", "file:///path/to/file")
+    expect(isSyntheticPart(part)).toBe(false)
+  })
+})
+
+describe("isFullySyntheticMessage", () => {
+  test("returns false for undefined", () => {
+    expect(isFullySyntheticMessage(undefined)).toBe(false)
+  })
+
+  test("returns false for empty array", () => {
+    expect(isFullySyntheticMessage([])).toBe(false)
+  })
+
+  test("returns false when all parts are non-synthetic", () => {
+    const parts = [
+      createTextPart("1", "hello"),
+      createFilePart("2", "file:///path"),
+    ]
+    expect(isFullySyntheticMessage(parts)).toBe(false)
+  })
+
+  test("returns false when some parts are synthetic", () => {
+    const parts = [
+      createTextPart("1", "user prompt"),
+      createTextPart("2", "file content", true),
+    ]
+    expect(isFullySyntheticMessage(parts)).toBe(false)
+  })
+
+  test("returns true when all parts are synthetic", () => {
+    const parts = [
+      createTextPart("1", "file content 1", true),
+      createTextPart("2", "file content 2", true),
+    ]
+    expect(isFullySyntheticMessage(parts)).toBe(true)
+  })
+})
+
+describe("filterSyntheticParts", () => {
+  test("returns empty array for undefined", () => {
+    expect(filterSyntheticParts(undefined)).toEqual([])
+  })
+
+  test("returns empty array for empty array", () => {
+    expect(filterSyntheticParts([])).toEqual([])
+  })
+
+  test("returns all parts when no synthetic parts exist", () => {
+    const parts = [
+      createTextPart("1", "hello"),
+      createFilePart("2", "file:///path"),
+    ]
+    expect(filterSyntheticParts(parts)).toEqual(parts)
+  })
+
+  test("filters out synthetic parts when non-synthetic parts exist", () => {
+    const userPart = createTextPart("1", "user prompt")
+    const syntheticPart = createTextPart("2", "file content", true)
+    const parts = [userPart, syntheticPart]
+    expect(filterSyntheticParts(parts)).toEqual([userPart])
+  })
+
+  test("keeps synthetic parts when all parts are synthetic", () => {
+    const parts = [
+      createTextPart("1", "file content 1", true),
+      createTextPart("2", "file content 2", true),
+    ]
+    expect(filterSyntheticParts(parts)).toEqual(parts)
+  })
+})