feat(desktop): uncap browser and terminal tabs

Author: Sg312

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

@@ -2,7 +2,6 @@ import { beforeEach, describe, expect, it, vi } from 'vitest'
 
 vi.mock('electron', () => import('@/test/electron-mock'))
 
-import { MAX_BROWSER_TABS } from '@sim/browser-protocol'
 import { sleep } from '@sim/utils/helpers'
 import { BrowserWindow, session as electronSession } from 'electron'
 import * as panel from '@/main/browser-agent/panel'
@@ -306,6 +305,33 @@ describe('browser-agent session', () => {
     )
   })
 
+  it('restores more than eight persisted tabs', () => {
+    const tabs = Array.from({ length: 12 }, (_, index) => ({
+      url: `https://tab-${index}.example/`,
+      pinned: index < 2,
+    }))
+    const { persistence } = memoryBrowserPersistence({
+      'chat-many-tabs': {
+        v: 1,
+        tabs,
+        activeIndex: tabs.length - 1,
+      },
+    })
+    session = freshSession(win, {}, undefined, persistence)
+
+    const restored = session.withBrowserScope('chat-many-tabs', () => {
+      session.restoreBrowserSession()
+      return session.getTabsState()
+    })
+
+    expect(restored.tabs).toHaveLength(12)
+    expect(restored.activeTabId).toBe('12')
+    expect(restored.tabs.at(-1)).toMatchObject({
+      url: 'https://tab-11.example/',
+      active: true,
+    })
+  })
+
   it('quiesces live scopes without publishing session closure', () => {
     const onTabsChanged = vi.fn()
     const onSessionClosed = vi.fn()
@@ -1034,16 +1060,22 @@ describe('browser-agent session', () => {
     ])
   })
 
-  it('limits the browser session to the shared tab cap', () => {
-    session.ensureTab()
-    for (let index = 1; index < MAX_BROWSER_TABS; index++) {
+  it('allows creation, duplication, and reopening beyond eight browser tabs', () => {
+    const first = session.ensureTab()
+    for (let index = 1; index < 12; index++) {
       session.addTab()
     }
 
-    expect(session.listTabs()).toHaveLength(MAX_BROWSER_TABS)
-    expect(() => session.addTab()).toThrow(
-      `The browser supports up to ${MAX_BROWSER_TABS} open tabs.`
-    )
+    expect(session.listTabs()).toHaveLength(12)
+    const duplicate = session.duplicateTab(first.id)
+    expect(duplicate).not.toBeNull()
+    expect(session.listTabs()).toHaveLength(13)
+    if (!duplicate) throw new Error('expected the tab to be duplicated')
+
+    session.closeTab(duplicate.id)
+    expect(session.listTabs()).toHaveLength(12)
+    expect(session.reopenClosedTab()).not.toBeNull()
+    expect(session.listTabs()).toHaveLength(13)
   })
 
   it('embeds the active view in the MAIN window only while panel bounds are reported', () => {

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

@@ -1,14 +1,13 @@
 import { AsyncLocalStorage } from 'node:async_hooks'
 import { join } from 'node:path'
-import {
-  type BrowserDataKind,
-  type BrowserFindRequest,
-  type BrowserFindResult,
-  type BrowserOmniboxFocusMode,
-  type BrowserTabState,
-  type BrowserTabsState,
-  type BrowserTheme,
-  MAX_BROWSER_TABS,
+import type {
+  BrowserDataKind,
+  BrowserFindRequest,
+  BrowserFindResult,
+  BrowserOmniboxFocusMode,
+  BrowserTabState,
+  BrowserTabsState,
+  BrowserTheme,
 } from '@sim/browser-protocol'
 import { createLogger } from '@sim/logger'
 import { getErrorMessage } from '@sim/utils/errors'
@@ -580,7 +579,6 @@ function sanitizePinnedTabUrls(value: unknown): string[] {
   for (const candidate of value) {
     const url = sanitizeRestorableUrl(candidate)
     if (url !== null) urls.push(url)
-    if (urls.length >= MAX_BROWSER_TABS) break
   }
   return urls
 }
@@ -605,7 +603,6 @@ function sanitizeBrowserSessionSnapshot(value: unknown): BrowserSessionSnapshotV
     const url = sanitizeRestorableUrl(entry.url)
     if (url === null) continue
     restoredTabs.push({ url, pinned: entry.pinned === true })
-    if (restoredTabs.length >= MAX_BROWSER_TABS) break
   }
 
   const requestedIndex =
@@ -1023,10 +1020,8 @@ function createTabView(): WebContentsView {
         return
       }
       if (shortcut === 'new-tab') {
-        if (listTabs().length < MAX_BROWSER_TABS) {
-          addTab()
-          focusRendererOmnibox('clear')
-        }
+        addTab()
+        focusRendererOmnibox('clear')
         return
       }
 
@@ -1217,9 +1212,6 @@ function addTabInternal({
   activate = true,
   notify = true,
 }: AddTabOptions = {}): AgentTab {
-  if (tabs.filter((tab) => !tab.view.webContents.isDestroyed()).length >= MAX_BROWSER_TABS) {
-    throw new SessionError(`The browser supports up to ${MAX_BROWSER_TABS} open tabs.`)
-  }
   const transferBrowserFocus =
     activate &&
     (currentScope.focusedBrowserTabId !== null ||
@@ -1340,7 +1332,6 @@ export function addTab(): AgentTab {
 /** Restores the most recently closed regular tab for the current app session. */
 export function reopenClosedTab(): AgentTab | null {
   restoreBrowserSession()
-  if (listTabs().length >= MAX_BROWSER_TABS) return null
   const url = recentlyClosedTabUrls.shift()
   if (!url) return null
 
@@ -1364,7 +1355,7 @@ export function reopenClosedTab(): AgentTab | null {
 export function duplicateTab(tabId: string): AgentTab | null {
   restoreBrowserSession()
   const source = tabs.find((entry) => entry.id === tabId)
-  if (!source || listTabs().length >= MAX_BROWSER_TABS) return null
+  if (!source) return null
 
   const url = sanitizeRestorableUrl(source.view.webContents.getURL())
   const tab = addTabInternal()

apps/desktop/src/main/desktop-chat-session-store.test.ts

@@ -214,8 +214,9 @@ describe('DesktopChatSessionStore', () => {
     )
   })
 
-  it('caps each snapshot at eight tabs and clamps its active index', () => {
-    const store = open()
+  it('preserves every browser and terminal tab while clamping active indexes', () => {
+    const provider = encryption()
+    const store = open(provider)
     store.setBrowser(ORIGIN, 'chat-a', {
       v: 1,
       tabs: Array.from({ length: 12 }, (_, index) => ({
@@ -227,15 +228,17 @@ describe('DesktopChatSessionStore', () => {
     store.setTerminal(ORIGIN, 'chat-a', {
       v: 1,
       tabs: Array.from({ length: 12 }, (_, index) => ({ cwd: `/tmp/tab-${index}` })),
-      activeIndex: -4,
+      activeIndex: 99,
     })
 
-    const browser = store.getBrowser(ORIGIN, 'chat-a')
-    const terminal = store.getTerminal(ORIGIN, 'chat-a')
-    expect(browser?.tabs).toHaveLength(8)
-    expect(browser?.activeIndex).toBe(7)
-    expect(terminal?.tabs).toHaveLength(8)
-    expect(terminal?.activeIndex).toBe(0)
+    expect(store.flush()).toBe(true)
+    const restarted = open(provider)
+    const browser = restarted.getBrowser(ORIGIN, 'chat-a')
+    const terminal = restarted.getTerminal(ORIGIN, 'chat-a')
+    expect(browser?.tabs).toHaveLength(12)
+    expect(browser?.activeIndex).toBe(11)
+    expect(terminal?.tabs).toHaveLength(12)
+    expect(terminal?.activeIndex).toBe(11)
   })
 
   it('filters unsafe or malformed values while loading an encrypted payload', () => {

apps/desktop/src/main/desktop-chat-session-store.ts

@@ -5,7 +5,6 @@ import { writeJsonFileAtomicallySync } from '@/main/atomic-json-file'
 const STORE_VERSION = 1
 const SNAPSHOT_VERSION = 1
 const MAX_DURABLE_ENTRIES = 100
-const MAX_TABS = 8
 const MAX_ORIGIN_LENGTH = 2_048
 const MAX_SCOPE_LENGTH = 512
 const MAX_URL_LENGTH = 8_192
@@ -134,7 +133,6 @@ function normalizeBrowserSnapshot(value: unknown): BrowserSessionSnapshot | null
 
   const tabs: BrowserSessionSnapshot['tabs'] = []
   for (const candidate of value.tabs) {
-    if (tabs.length === MAX_TABS) break
     if (!isRecord(candidate) || typeof candidate.pinned !== 'boolean') continue
     const url = normalizeBrowserUrl(candidate.url)
     if (url === null) continue
@@ -153,7 +151,6 @@ function normalizeTerminalSnapshot(value: unknown): TerminalSessionSnapshot | nu
 
   const tabs: TerminalSessionSnapshot['tabs'] = []
   for (const candidate of value.tabs) {
-    if (tabs.length === MAX_TABS) break
     if (!isRecord(candidate) || typeof candidate.cwd !== 'string') continue
     if (
       candidate.cwd.trim().length === 0 ||

apps/desktop/src/main/terminal/index.ts

@@ -17,7 +17,6 @@ import {
   isTerminalControlKey,
   MAX_INPUT_KEYS,
   MAX_RUN_WAIT_MS,
-  MAX_TERMINALS,
   MAX_TOOL_OUTPUT_CHARS,
   type TerminalCommandEvent,
   type TerminalControlKey,
@@ -75,6 +74,9 @@ const INPUT_SCREEN_LINES = 60
  */
 const CWD_POLL_MS = 1_000
 
+/** Cmd-Shift-T history; independent of how many terminals may be open. */
+const MAX_RECENTLY_CLOSED_TERMINALS = 10
+
 /** Pause between keys sent to a tmux pane, matching the pty keystroke gap. */
 const TMUX_KEY_GAP_MS = 150
 
@@ -258,12 +260,6 @@ export class TerminalService {
 
   /** Opens an additional terminal and makes it active. */
   openTerminal(cwd?: string): TerminalTabsState {
-    if (this.sessions.size >= MAX_TERMINALS) {
-      throw new TerminalError(
-        'TOO_MANY_TERMINALS',
-        `Up to ${MAX_TERMINALS} terminals can be open at once. Close one first.`
-      )
-    }
     const active = this.activeId ? this.sessions.get(this.activeId) : null
     const size = active ? { cols: active.cols, rows: active.rows } : { cols: 80, rows: 24 }
     // A new terminal opens where the current one is: the user is almost always
@@ -375,9 +371,7 @@ export class TerminalService {
    */
   reopenClosedTerminal(ownerWindow: BrowserWindow | null): boolean {
     if (!this.ownsInteraction(ownerWindow)) return false
-    // Peeked, not shifted: at the cap there is nothing to reopen into, and
-    // consuming the entry here would drop that directory on the floor.
-    if (this.recentlyClosedCwds.length === 0 || this.sessions.size >= MAX_TERMINALS) return false
+    if (this.recentlyClosedCwds.length === 0) return false
     const cwd = this.recentlyClosedCwds.shift()
     this.openTerminal(cwd || undefined)
     return true
@@ -458,8 +452,8 @@ export class TerminalService {
 
   private rememberClosed(cwd: string | null): void {
     this.recentlyClosedCwds.unshift(cwd ?? '')
-    if (this.recentlyClosedCwds.length > MAX_TERMINALS) {
-      this.recentlyClosedCwds.length = MAX_TERMINALS
+    if (this.recentlyClosedCwds.length > MAX_RECENTLY_CLOSED_TERMINALS) {
+      this.recentlyClosedCwds.length = MAX_RECENTLY_CLOSED_TERMINALS
     }
   }
 

apps/desktop/src/main/terminal/registry.test.ts

@@ -194,11 +194,14 @@ describe('TerminalRegistry', () => {
   })
 
   it('restores saved tab directories lazily as fresh shells', () => {
+    const persistedTabs = Array.from({ length: 12 }, (_, index) => ({
+      cwd: index % 2 === 0 ? tmpdir() : process.cwd(),
+    }))
     const persistence: TerminalScopePersistence = {
       load: vi.fn(() => ({
         v: 1 as const,
-        tabs: [{ cwd: '/tmp' }, { cwd: '/private/tmp' }],
-        activeIndex: 1,
+        tabs: persistedTabs,
+        activeIndex: 11,
       })),
       save: vi.fn(),
       migrate: vi.fn(),
@@ -214,18 +217,18 @@ describe('TerminalRegistry', () => {
 
     const restored = terminals.start('chat-A', { cols: 120, rows: 40 })
 
-    expect(stubSessions.map(({ cwd }) => cwd)).toEqual(['/tmp', '/private/tmp'])
+    expect(stubSessions.map(({ cwd }) => cwd)).toEqual(persistedTabs.map(({ cwd }) => cwd))
     expect(restored).toMatchObject({
-      activeTerminalId: '2',
-      tabs: [
-        { terminalId: '1', cwd: '/tmp' },
-        { terminalId: '2', cwd: '/private/tmp' },
-      ],
+      activeTerminalId: '12',
+      tabs: persistedTabs.map(({ cwd }, index) => ({
+        terminalId: String(index + 1),
+        cwd,
+      })),
     })
     expect(persistence.save).toHaveBeenLastCalledWith('chat-A', {
       v: 1,
-      tabs: [{ cwd: '/tmp' }, { cwd: '/private/tmp' }],
-      activeIndex: 1,
+      tabs: persistedTabs,
+      activeIndex: 11,
     })
 
     terminals.dispose()

apps/desktop/src/main/terminal/service.test.ts

@@ -1,7 +1,6 @@
 import { mkdtempSync } from 'node:fs'
 import { tmpdir } from 'node:os'
 import { join } from 'node:path'
-import { MAX_TERMINALS } from '@sim/terminal-protocol'
 import { describe, expect, it, vi } from 'vitest'
 import { TerminalService } from '@/main/terminal'
 
@@ -272,28 +271,22 @@ describe('focus-gated shortcuts', () => {
     expect(terminal.closeFocusedTerminal(renderer.window)).toBe(true)
   })
 
-  it('does not consume the reopen history when already at the terminal cap', () => {
+  it('opens and reopens more than eight terminals', () => {
     const terminal = service()
     terminal.start({ cols: 80, rows: 24 })
     const renderer = rendererStub()
     terminal.setPanelFocused(true, renderer.contents)
 
     const closed = terminal.openTerminal('/alpha')
     terminal.closeTerminal(closed.activeTerminalId as string)
-    while (terminal.getTabs().tabs.length < MAX_TERMINALS) terminal.openTerminal()
+    while (terminal.getTabs().tabs.length < 12) terminal.openTerminal()
 
-    // Refused, and without opening anything.
-    expect(terminal.reopenClosedTerminal(renderer.window)).toBe(false)
-    expect(terminal.getTabs().tabs).toHaveLength(MAX_TERMINALS)
-
-    // NOTE: that the '/alpha' entry SURVIVES the refusal is the actual point of
-    // the guard, and it is not observable from out here — every close prepends
-    // one history entry and frees exactly one slot, so a reopen can never walk
-    // back past the entries created by the closes that made room for it. The
-    // ordering in reopenClosedTerminal (check the cap, then shift) is what
-    // carries it; this test only pins the refusal itself.
-    terminal.closeTerminal(terminal.getTabs().activeTerminalId as string)
     expect(terminal.reopenClosedTerminal(renderer.window)).toBe(true)
+    const reopened = terminal.getTabs()
+    expect(reopened.tabs).toHaveLength(13)
+    expect(
+      reopened.tabs.find(({ terminalId }) => terminalId === reopened.activeTerminalId)?.cwd
+    ).toBe('/alpha')
   })
 
   it('ignores a blur reported by a renderer that does not hold the claim', () => {

apps/sim/app/workspace/[workspaceId]/home/components/mothership-view/components/resource-content/components/browser-session/browser-tab-strip.tsx

@@ -7,7 +7,7 @@ import {
   useMemo,
   useState,
 } from 'react'
-import { type BrowserTabState, MAX_BROWSER_TABS } from '@sim/browser-protocol'
+import type { BrowserTabState } from '@sim/browser-protocol'
 import { TabStrip, type TabStripItem } from '@sim/emcn'
 import { Link, Loader } from '@sim/emcn/icons'
 import { SIM_RESOURCE_DRAG_TYPE } from '@/lib/copilot/resource-types'
@@ -138,7 +138,6 @@ export function BrowserTabStrip({
       onNew={onNewTab}
       onTabContextMenu={openTabContextMenu}
       onTabDragStart={startTabDrag}
-      maxTabs={MAX_BROWSER_TABS}
       {...(reorderingSupported ? { onReorder: onReorderTab } : {})}
     >
       <ContextMenu
@@ -161,7 +160,6 @@ export function BrowserTabStrip({
         isPinned={Boolean(contextTab?.pinned)}
         showRename={false}
         showDuplicate={Boolean(contextTab)}
-        disableDuplicate={tabs.length >= MAX_BROWSER_TABS}
         showDelete={false}
       />
     </TabStrip>