fix(terminal): harden remote parking under load

src/renderer/src/components/Terminal.tsx

@@ -93,6 +93,7 @@ import {
 } from './terminal-pane/terminal-hidden-view-parking'
 import {
   TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS,
+  selectTerminalLayoutPaneCountByTabId,
   selectForceParkEvictableTabIds,
   selectRetentionForceParkedTerminalWorktrees,
   type TerminalWorktreeRetentionCandidate
@@ -293,9 +294,11 @@ function Terminal(): React.JSX.Element | null {
   )
   const activeView = useAppStore((s) => s.activeView)
   const tabsByWorktree = useAppStore((s) => s.tabsByWorktree)
+  const terminalLayoutPaneCountByTabId = useAppStore(selectTerminalLayoutPaneCountByTabId)
   const pendingStartupByTabId = useAppStore((s) => s.pendingStartupByTabId)
   const terminalParkingEnabled = useAppStore((s) => s.settings?.terminalHiddenViewParking !== false)
   const terminalSshParkingEnabled = useAppStore((s) => s.settings?.terminalSshViewParking !== false)
+  const terminalScrollbackRows = useAppStore((s) => s.settings?.terminalScrollbackRows)
   const terminalRetentionBudgetEnabled = useAppStore(
     (s) => s.settings?.terminalHiddenWorktreeRetentionBudget !== false
   )
@@ -978,8 +981,8 @@ function Terminal(): React.JSX.Element | null {
         nextParkedTerminalWorktreeIds.delete(worktreeId)
       }
     }
-    // C1 retention budget: worktrees ordinary parking can never evict (SSH off,
-    // remote-runtime, uncoverable tabs) force-park beyond a count/TTL bound —
+    // Worktrees ordinary parking cannot evict (SSH off, remote-runtime,
+    // uncoverable tabs) force-park beyond the pane-weight budget or TTL —
     // added AFTER the coverage veto because darkness for their uncoverable tabs
     // is the accepted cost of bounding retention.
     const retentionBudgetCandidates: TerminalWorktreeRetentionCandidate[] = retentionCandidates.map(
@@ -1014,6 +1017,10 @@ function Terminal(): React.JSX.Element | null {
               pendingStartupByTabId[tab.id] !== undefined ||
               tab.pendingActivationSpawn === true ||
               (typeof tab.pendingActivationSpawn === 'number' && tab.pendingActivationSpawn > 0)
+          ),
+          retainedPaneCount: tabs.reduce(
+            (count, tab) => count + (terminalLayoutPaneCountByTabId[tab.id] ?? 1),
+            0
           )
         }
       }
@@ -1023,6 +1030,7 @@ function Terminal(): React.JSX.Element | null {
       parkingEnabled: terminalParkingEnabled,
       retentionBudgetEnabled: terminalRetentionBudgetEnabled,
       nowMs,
+      scrollbackRows: terminalScrollbackRows,
       ...overrides
     })
     const capturedForceParked = forceParkedCaptureDoneRef.current
@@ -1047,9 +1055,7 @@ function Terminal(): React.JSX.Element | null {
         // uses), so SSH classes whose reveal has no local snapshot still show
         // last-known content. includeLocalBuffers:false is required here, not
         // optional — a heap fix must not plant 512KB/pane of scrollback strings
-        // in the store for local worktrees that already have the daemon
-        // snapshot; a remote-runtime pane in a local repo likewise needs none,
-        // its reveal repaints from the runtime's own subscribe snapshot.
+        // in the store when the daemon/runtime already owns the snapshot.
         // Eviction-exempt tabs never unmount (per-tab exclusion), so they need
         // no pre-unmount capture — skipping spares a serialize+setTabLayout
         // walk on live panes per force-park episode.
@@ -1128,9 +1134,11 @@ function Terminal(): React.JSX.Element | null {
     pendingStartupByTabId,
     renderedActiveWorktreeId,
     tabsByWorktree,
+    terminalLayoutPaneCountByTabId,
     terminalParkingEnabled,
     terminalParkingRevision,
     terminalRetentionBudgetEnabled,
+    terminalScrollbackRows,
     terminalSshParkingEnabled,
     workspaceSurfaces
   ])

src/renderer/src/components/terminal-pane/TerminalPane.tsx

@@ -127,7 +127,10 @@ import { resolvePaneKeyForManager } from '@/lib/pane-manager/pane-key-resolution
 import { safeFit, safeFitAndThen } from '@/lib/pane-manager/pane-tree-ops'
 import { applyDesktopFitFallbackAfterReplay } from './desktop-fit-fallback'
 import { clearTerminalScrollbackAndFollowOutput } from '@/lib/pane-manager/terminal-scrollback-clear'
-import { captureTerminalShutdownLayout } from './terminal-shutdown-layout-capture'
+import {
+  captureTerminalShutdownLayout,
+  selectRemoteRuntimeScrollbackLeafIds
+} from './terminal-shutdown-layout-capture'
 import { getOverrideAffectedPanes, getPanesNeedingOverrideFit } from './override-affected-panes'
 import {
   inspectRuntimeTerminalProcess,
@@ -200,7 +203,10 @@ function isInsideNativeChatRoot(target: EventTarget | null): boolean {
 }
 
 // Why: registry lives in a leaf module to break the slice → TerminalPane → store → slice import cycle that leaves createTerminalSlice undefined at init.
-import { shutdownBufferCaptures } from './shutdown-buffer-captures'
+import {
+  shutdownBufferCaptures,
+  type ShutdownBufferCaptureOptions
+} from './shutdown-buffer-captures'
 import { mergeCapturedLeafState } from './merge-captured-leaf-state'
 import { pasteTerminalText } from './terminal-bracketed-paste'
 import {
@@ -2370,7 +2376,7 @@ function TerminalPane(
 
   // Register a shutdown capture callback; App.tsx's beforeunload handler invokes all to serialize terminal buffers.
   useEffect(() => {
-    const captureBuffers = (options?: { includeLocalBuffers?: boolean }): void => {
+    const captureBuffers = (options?: ShutdownBufferCaptureOptions): void => {
       const manager = managerRef.current
       const container = containerRef.current
       if (!manager || !container) {
@@ -2384,19 +2390,29 @@ function TerminalPane(
       const state = useAppStore.getState()
       const existing = state.terminalLayoutsByTabId[tabId]
       const includeLocalBuffers = options?.includeLocalBuffers ?? true
+      const paneTransports = paneTransportsRef.current
       const shouldCaptureScrollbackBuffers = includeLocalBuffers
         ? true
         : shouldPreserveTerminalScrollbackBuffers(worktreeId, state.repos)
+      const excludedScrollbackLeafIds =
+        options?.excludeRemoteRuntimeScrollback === true
+          ? selectRemoteRuntimeScrollbackLeafIds({
+              panes,
+              paneTransports,
+              existingLayout: existing
+            })
+          : undefined
       const layout = captureTerminalShutdownLayout({
         manager,
         container,
         expandedPaneId: expandedPaneIdRef.current,
-        paneTransports: paneTransportsRef.current,
+        paneTransports,
         paneTitlesByPaneId: paneTitlesRef.current,
         existingLayout: existing,
         // Why: beforeunload skips local/floating bytes (session payloads prune them); worktree sleep keeps them as defense-in-depth.
         captureBuffers: shouldCaptureScrollbackBuffers,
-        clearedScrollbackLeafIds: clearedScrollbackLeafIdsRef.current
+        clearedScrollbackLeafIds: clearedScrollbackLeafIdsRef.current,
+        excludedScrollbackLeafIds
       })
       setTabLayout(tabId, layout)
       for (const pane of panes) {

src/renderer/src/components/terminal-pane/force-park-buffer-capture.test.ts

@@ -44,7 +44,10 @@ describe('captureForceParkedWorktreeBuffers', () => {
     })
 
     expect(captured).toBe(true)
-    expect(capture).toHaveBeenCalledWith({ includeLocalBuffers: false })
+    expect(capture).toHaveBeenCalledWith({
+      includeLocalBuffers: false,
+      excludeRemoteRuntimeScrollback: true
+    })
   })
 
   it('reports an incomplete episode when a tab has no registered capture', () => {

src/renderer/src/components/terminal-pane/force-park-buffer-capture.ts

@@ -23,7 +23,8 @@ export function captureForceParkedWorktreeBuffers({
     return true
   }
   const { requested, captured } = captureTerminalShutdownBuffersBestEffort(tabIds, {
-    includeLocalBuffers: false
+    includeLocalBuffers: false,
+    excludeRemoteRuntimeScrollback: true
   })
   return captured === requested
 }

src/renderer/src/components/terminal-pane/pty-connection.test.ts

@@ -192,6 +192,7 @@ type StoreState = {
     localWindowsRuntimeDefault?: { kind: 'windows-host' } | { kind: 'wsl'; distro: string | null }
     terminalMainSideEffectAuthority?: boolean
     terminalHiddenDeliveryGate?: boolean
+    terminalSshViewParking?: boolean
     notifications?: {
       enabled?: boolean
       agentTaskComplete?: boolean
@@ -19896,9 +19897,13 @@ describe('connectPanePty', () => {
 
     const pane = createPane(1)
     const { writes } = captureCallbackTerminalWrites(pane)
+    pane.terminal.write(
+      `captured-early-marker\r\n${Array.from({ length: 12 }, (_, index) => `captured-${index}\r\n`).join('')}`
+    )
     const deps = createDeps({
       restoredLeafId: LEAF_1,
-      restoredPtyIdByLeafId: { [LEAF_1]: sshPtyId }
+      restoredPtyIdByLeafId: { [LEAF_1]: sshPtyId },
+      restoredViewportBlankingPanesRef: { current: new Set([1]) }
     })
 
     connectPanePty(pane as never, createManager(1) as never, deps as never)
@@ -19913,6 +19918,11 @@ describe('connectPanePty', () => {
     await flushAsyncTicks(20)
 
     expect(writes).toContain('relay-fallback-output')
+    expect(writes).toContain('\x1b[2J\x1b[H')
+    expect(writes).not.toContain('\x1b[2J\x1b[3J\x1b[H')
+    expect((await renderHeadlessBuffer(writes, 80, 6)).join('\n')).toContain(
+      'captured-early-marker'
+    )
     // Why: a stalled reveal must cost exactly one bounded probe — a re-probe
     // would buy a second timeout window before the relay paint.
     expect(window.api.pty.getMainBufferSnapshot).toHaveBeenCalledTimes(1)
@@ -19954,6 +19964,47 @@ describe('connectPanePty', () => {
     expect(writes).toContain('relay-reconnect-output')
   })
 
+  it('preserves restored scrollback through relay replay without a parked watcher', async () => {
+    const { connectPanePty } = await import('./pty-connection')
+    const sshPtyId = toAppSshPtyId('conn-1', 'relay-pty-1')
+    const transport = createMockTransport(sshPtyId)
+    transport.connect.mockImplementation(async () => {
+      transport.getPtyId.mockReturnValue(sshPtyId)
+      return { id: sshPtyId, isReattach: true, replay: 'relay-reconnect-output' }
+    })
+    transportFactoryQueue.push(transport)
+
+    mockStoreState = {
+      ...mockStoreState,
+      settings: { ...mockStoreState.settings, terminalSshViewParking: false },
+      tabsByWorktree: { 'wt-1': [{ id: 'tab-1', ptyId: null }] },
+      repos: [{ id: 'repo1', connectionId: 'conn-1' }],
+      deferredSshReconnectTargets: ['conn-1'],
+      deferredSshSessionIdsByTabId: { 'tab-1': sshPtyId }
+    }
+
+    const pane = createPane(1)
+    const { writes } = captureCallbackTerminalWrites(pane)
+    pane.terminal.write(
+      `captured-early-marker\r\n${Array.from({ length: 12 }, (_, index) => `captured-${index}\r\n`).join('')}`
+    )
+    const deps = createDeps({
+      restoredLeafId: LEAF_1,
+      restoredPtyIdByLeafId: { [LEAF_1]: sshPtyId },
+      restoredViewportBlankingPanesRef: { current: new Set([1]) }
+    })
+
+    connectPanePty(pane as never, createManager(1) as never, deps as never)
+    await flushAsyncTicks(20)
+
+    expect(window.api.pty.getMainBufferSnapshot).not.toHaveBeenCalled()
+    expect(writes).toContain('\x1b[2J\x1b[H')
+    expect(writes).not.toContain('\x1b[2J\x1b[3J\x1b[H')
+    expect((await renderHeadlessBuffer(writes, 80, 6)).join('\n')).toContain(
+      'captured-early-marker'
+    )
+  })
+
   it('does not auto-reconnect after a user cancels deferred SSH passphrase auth', async () => {
     const { connectPanePty } = await import('./pty-connection')
     const transport = createMockTransport()

src/renderer/src/components/terminal-pane/pty-connection.ts

@@ -7663,6 +7663,8 @@ export function connectPanePty(
       const revealFollowsTerminalPark =
         mountFollowsTerminalPark && connectResult?.isReattach === true
       mountFollowsTerminalPark = false
+      const hasRestoredScrollback =
+        deps.restoredViewportBlankingPanesRef?.current.has(pane.id) ?? false
       // Why: a relay restart empties the replay buffer, but main's model may
       // still hold the session — a park-reveal probes it even with no replay
       // so the reveal is never blank when main has content. Prefetched (before
@@ -7769,8 +7771,8 @@ export function connectPanePty(
             }
           } else if (connectResult?.replay) {
             rememberReattachPayloadAgentSignal(connectResult.replay, { fullScreenReplay: true })
-            // Relay replay may overlap xterm's pre-disconnect content; clear first to avoid duplication.
-            writeReplayData('\x1b[2J\x1b[3J\x1b[H')
+            // A restored capture may be the only history outside the relay's 100KiB tail.
+            writeReplayData(hasRestoredScrollback ? '\x1b[2J\x1b[H' : '\x1b[2J\x1b[3J\x1b[H')
             // Why: raw relay replay may contain the app's own kitty pushes; re-arm with set semantics so redelivery can't grow the stack.
             kittyKeyboardModes.scanReplay(connectResult.replay)
             writeReplayData(connectResult.replay)

src/renderer/src/components/terminal-pane/pty-transport.test.ts

@@ -929,6 +929,96 @@ describe('createIpcPtyTransport', () => {
     }
   })
 
+  it('preserves the latest agent lifecycle transition through queue eviction', async () => {
+    vi.useFakeTimers()
+    try {
+      const { createPtyOutputProcessor, MAX_PENDING_PTY_SIDE_EFFECTS } =
+        await import('./pty-transport')
+      const onAgentBecameWorking = vi.fn()
+      const onAgentBecameIdle = vi.fn()
+      const processor = createPtyOutputProcessor({
+        onTitleChange: vi.fn(),
+        onAgentBecameWorking,
+        onAgentBecameIdle
+      })
+      const callbacks = { onData: vi.fn() }
+
+      processor.processData('\x1b]0;. Claude working\x07', callbacks)
+      for (let i = 0; i < MAX_PENDING_PTY_SIDE_EFFECTS; i++) {
+        processor.processData(`\x1b]0;shell-title-${i}\x07`, callbacks)
+      }
+      processor.processData('\x1b]0;* Claude idle\x07', callbacks)
+      processor.flushPendingSideEffects()
+
+      expect(onAgentBecameWorking).toHaveBeenCalledTimes(1)
+      expect(onAgentBecameIdle).toHaveBeenCalledTimes(1)
+    } finally {
+      vi.useRealTimers()
+    }
+  })
+
+  it('resets stale-title timing when a working title survives queue eviction', async () => {
+    vi.useFakeTimers()
+    try {
+      const { createPtyOutputProcessor, MAX_PENDING_PTY_SIDE_EFFECTS } =
+        await import('./pty-transport')
+      const onAgentBecameIdle = vi.fn()
+      const processor = createPtyOutputProcessor({
+        onTitleChange: vi.fn(),
+        onAgentBecameWorking: vi.fn(),
+        onAgentBecameIdle,
+        onAgentStatus: vi.fn()
+      })
+      const callbacks = { onData: vi.fn() }
+
+      processor.processData('\x1b]0;. Claude working\x07', callbacks)
+      await vi.advanceTimersByTimeAsync(0)
+      processor.processData('plain output\r\n', callbacks)
+      await vi.advanceTimersByTimeAsync(0)
+      await vi.advanceTimersByTimeAsync(2_900)
+
+      processor.processData('\x1b]0;. Claude working\x07', callbacks)
+      for (let i = 0; i < MAX_PENDING_PTY_SIDE_EFFECTS; i++) {
+        processor.processData(`\x1b]9999;{"state":"working","prompt":"${i}"}\x07`, callbacks)
+      }
+      processor.flushPendingSideEffects()
+      await vi.advanceTimersByTimeAsync(100)
+
+      expect(onAgentBecameIdle).not.toHaveBeenCalled()
+    } finally {
+      vi.useRealTimers()
+    }
+  })
+
+  it('preserves an agent exit title through queue eviction', async () => {
+    vi.useFakeTimers()
+    try {
+      const { createPtyOutputProcessor, MAX_PENDING_PTY_SIDE_EFFECTS } =
+        await import('./pty-transport')
+      const onAgentExited = vi.fn()
+      const processor = createPtyOutputProcessor({
+        onTitleChange: vi.fn(),
+        onAgentBecameWorking: vi.fn(),
+        onAgentBecameIdle: vi.fn(),
+        onAgentExited,
+        onAgentStatus: vi.fn()
+      })
+      const callbacks = { onData: vi.fn() }
+
+      processor.processData('\x1b]0;. Claude working\x07', callbacks)
+      processor.processData('\x1b]0;* Claude idle\x07', callbacks)
+      processor.processData('\x1b]0;shell prompt\x07', callbacks)
+      for (let i = 0; i < MAX_PENDING_PTY_SIDE_EFFECTS; i++) {
+        processor.processData(`\x1b]9999;{"state":"working","prompt":"${i}"}\x07`, callbacks)
+      }
+      processor.flushPendingSideEffects()
+
+      expect(onAgentExited).toHaveBeenCalledTimes(1)
+    } finally {
+      vi.useRealTimers()
+    }
+  })
+
   it('collapses evicted agent-status payloads onto the survivor, keeping the newest', async () => {
     vi.useFakeTimers()
     try {

src/renderer/src/components/terminal-pane/pty-transport.ts

@@ -108,6 +108,11 @@ type PendingPtySideEffect = {
   suppressAttentionEvents: boolean
 }
 
+type EvictedAgentTitleTransition = {
+  phase: 'working' | 'settled' | 'cleared'
+  title: string
+}
+
 function isIgnoredCursorNativeTitle(title: string): boolean {
   return title.trim().toLowerCase() === 'cursor agent'
 }
@@ -165,6 +170,7 @@ export function createPtyOutputProcessor({
   let pendingSideEffects: PendingPtySideEffect[] = []
   let pendingSideEffectIndex = 0
   let pendingWorkingTitleSideEffects = 0
+  let evictedAgentTitleTransitions: EvictedAgentTitleTransition[] = []
   const agentTracker =
     onAgentBecameIdle || onAgentBecameWorking || onAgentExited
       ? createAgentStatusTracker(
@@ -199,6 +205,37 @@ export function createPtyOutputProcessor({
     }
   }
 
+  function carryEvictedAgentTitleTransitions(next: PendingPtySideEffect): void {
+    if (!agentTracker || next.suppressAttentionEvents) {
+      return
+    }
+    for (const title of next.titles) {
+      const status = detectAgentStatusFromTitle(title)
+      const phase = status === 'working' ? 'working' : status === null ? 'cleared' : 'settled'
+      const prior = evictedAgentTitleTransitions.at(-1)
+      if (prior?.phase === phase) {
+        prior.title = title
+        continue
+      }
+      evictedAgentTitleTransitions.push({ phase, title })
+      if (evictedAgentTitleTransitions.length > 3) {
+        evictedAgentTitleTransitions.shift()
+      }
+    }
+  }
+
+  function flushEvictedAgentTitleTransitions(): void {
+    const transitions = evictedAgentTitleTransitions
+    evictedAgentTitleTransitions = []
+    if (transitions.length > 0) {
+      // Carried titles are fresh observations; an older fallback must not clear them.
+      clearStaleTitleTimer()
+    }
+    for (const transition of transitions) {
+      applyObservedTerminalTitle(transition.title)
+    }
+  }
+
   function clearStaleTitleTimer(): void {
     if (staleTitleTimer) {
       clearTimeout(staleTitleTimer)
@@ -214,9 +251,8 @@ export function createPtyOutputProcessor({
     sideEffectDrainTimer = setTimeout(drainPtySideEffects, 0)
   }
 
-  // Why: oldest-first eviction at the cap. Evicted titles are safe to drop (titles are last-wins);
-  // bells and agent-status payloads collapse onto the next-oldest survivor so a pending bell latch
-  // and the newest statuses still apply on drain instead of vanishing.
+  // Why: oldest-first eviction at the cap. Display titles are last-wins, lifecycle phases carry
+  // separately, and bells/statuses collapse onto the next survivor instead of vanishing.
   function evictOldestPendingSideEffectsIfFull(): void {
     while (pendingSideEffects.length - pendingSideEffectIndex >= MAX_PENDING_PTY_SIDE_EFFECTS) {
       const evicted = pendingSideEffects[pendingSideEffectIndex]
@@ -224,6 +260,8 @@ export function createPtyOutputProcessor({
         return
       }
       pendingSideEffectIndex += 1
+      // Why: the queue may drop display titles, but the latest agent lifecycle edge must survive.
+      carryEvictedAgentTitleTransitions(evicted)
       // Why: mirror applyPtySideEffect's accounting so stale-probe arming doesn't stick past eviction.
       pendingWorkingTitleSideEffects -= countWorkingTitles(evicted.titles)
       if (pendingWorkingTitleSideEffects < 0) {
@@ -288,7 +326,9 @@ export function createPtyOutputProcessor({
       data.length > 0 &&
       titles.length === 0 &&
       !suppressAttentionEvents &&
-      (isWorkingTitle(lastEmittedTitle) || pendingWorkingTitleSideEffects > 0)
+      (isWorkingTitle(lastEmittedTitle) ||
+        pendingWorkingTitleSideEffects > 0 ||
+        evictedAgentTitleTransitions.some((transition) => transition.phase === 'working'))
     )
     const shouldEmitEmptyTitleScan = scannedForTitles || needsStaleTitleProbe
     const emptyTitleScanEffect: PendingPtySideEffect['titleScanEffect'] = ignoredCursorNativeTitle
@@ -390,6 +430,7 @@ export function createPtyOutputProcessor({
 
   function drainPtySideEffects(options: { flushAll?: boolean } = {}): void {
     sideEffectDrainTimer = null
+    flushEvictedAgentTitleTransitions()
     const maxEffects = options.flushAll ? Number.POSITIVE_INFINITY : MAX_PTY_SIDE_EFFECTS_PER_DRAIN
     let processed = 0
     while (pendingSideEffectIndex < pendingSideEffects.length && processed < maxEffects) {
@@ -488,6 +529,7 @@ export function createPtyOutputProcessor({
     pendingSideEffects.length = 0
     pendingSideEffectIndex = 0
     pendingWorkingTitleSideEffects = 0
+    evictedAgentTitleTransitions.length = 0
     clearStaleTitleTimer()
     agentTracker?.reset()
     bellDetector.reset()

src/renderer/src/components/terminal-pane/shutdown-buffer-captures.ts

@@ -1,5 +1,7 @@
 export type ShutdownBufferCaptureOptions = {
   includeLocalBuffers?: boolean
+  /** Force-parking remote-runtime panes restores from the host snapshot. */
+  excludeRemoteRuntimeScrollback?: boolean
 }
 
 /** Map of tabId → buffer-capture callback, one per mounted TerminalPane.

src/renderer/src/components/terminal-pane/terminal-eviction-exempt-tabs.test.ts

@@ -41,9 +41,24 @@ describe('selectEvictionExemptTerminalTabLayoutKey', () => {
     ).not.toBe(selectEvictionExemptTerminalTabLayoutKey(layoutState({ [LEAF_ID]: PTY_ID }), TABS))
   })
 
+  it('does not collide when a pty id contains layout-key delimiters', () => {
+    const embeddedLeaf = `pty-local-detached,${SECOND_LEAF_ID}:second`
+    expect(
+      selectEvictionExemptTerminalTabLayoutKey(layoutState({ [LEAF_ID]: embeddedLeaf }), TABS)
+    ).not.toBe(
+      selectEvictionExemptTerminalTabLayoutKey(
+        layoutState({
+          [LEAF_ID]: 'pty-local-detached',
+          [SECOND_LEAF_ID]: 'second'
+        }),
+        TABS
+      )
+    )
+  })
+
   it('tolerates tabs with no persisted layout', () => {
     expect(selectEvictionExemptTerminalTabLayoutKey({ terminalLayoutsByTabId: {} }, TABS)).toBe(
-      `${TAB_ID}=`
+      JSON.stringify([[TAB_ID, []]])
     )
   })
 })

src/renderer/src/components/terminal-pane/terminal-eviction-exempt-tabs.ts

@@ -75,13 +75,12 @@ export function selectEvictionExemptTerminalTabLayoutKey(
   state: EvictionExemptTabLayoutState,
   tabs: readonly ParkableTerminalTabModel[]
 ): string {
-  return tabs
-    .map((tab) => {
-      const ptyIdsByLeafId = state.terminalLayoutsByTabId[tab.id]?.ptyIdsByLeafId ?? {}
-      const leafPtys = Object.entries(ptyIdsByLeafId)
-        .map(([leafId, ptyId]) => `${leafId}:${ptyId}`)
-        .join(',')
-      return `${tab.id}=${leafPtys}`
-    })
-    .join('|')
+  return JSON.stringify(
+    tabs.map((tab) => [
+      tab.id,
+      Object.entries(state.terminalLayoutsByTabId[tab.id]?.ptyIdsByLeafId ?? {}).sort(
+        ([leftLeafId], [rightLeafId]) => leftLeafId.localeCompare(rightLeafId)
+      )
+    ])
+  )
 }

src/renderer/src/components/terminal-pane/terminal-hidden-view-parking.ts

@@ -25,6 +25,7 @@ export type TerminalColdParkPolicyOverrides = {
   hotRetainMs?: number
   hotRetainLimit?: number
   retentionTtlMs?: number
+  /** Default-scrollback pane units for un-parkable hidden renderer views. */
   retentionLimit?: number
 }
 

src/renderer/src/components/terminal-pane/terminal-hidden-worktree-retention.test.ts

@@ -2,9 +2,12 @@ import { describe, expect, it } from 'vitest'
 import { TERMINAL_WORKTREE_PARK_DELAY_MS } from './terminal-hidden-view-parking'
 import {
   TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS,
+  countTerminalLayoutPanes,
+  getTerminalHiddenPaneRetentionWeight,
   isEvictionExemptTerminalPty,
   selectForceParkEvictableTabIds,
   selectRetentionForceParkedTerminalWorktrees,
+  selectTerminalLayoutPaneCountByTabId,
   type TerminalWorktreeRetentionCandidate
 } from './terminal-hidden-worktree-retention'
 
@@ -40,6 +43,7 @@ describe('selectRetentionForceParkedTerminalWorktrees', () => {
       hasActivityTerminalPortal: false,
       ordinaryParkingCovers: false,
       hasPendingSpawnWork: false,
+      retainedPaneCount: 1,
       ...partial
     }
   }
@@ -73,13 +77,62 @@ describe('selectRetentionForceParkedTerminalWorktrees', () => {
       retentionCandidate('wt-3', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS - 1),
       retentionCandidate('wt-4', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS)
     ]
-    // Why limit 2: wt-4 is last-active exempt, wt-3 fills the remaining slot; the two oldest evict.
+    // Why limit 2: newest wt-4 claims one unit, wt-3 claims the other; the two oldest evict.
     expect(
       selectRetentionForceParkedTerminalWorktrees({ ...base, worktrees, retentionLimit: 2 })
     ).toEqual(new Set(['wt-1', 'wt-2']))
   })
 
-  it('force-parks past the TTL even under the limit, sparing a last-active candidate inside it', () => {
+  it('force-parks a newest candidate that exceeds the pane budget by itself', () => {
+    const worktrees = [
+      retentionCandidate('wt-many-panes', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS, {
+        retainedPaneCount: 13
+      })
+    ]
+
+    expect(selectRetentionForceParkedTerminalWorktrees({ ...base, worktrees })).toEqual(
+      new Set(['wt-many-panes'])
+    )
+  })
+
+  it('spends the budget on the newest weighted worktrees first', () => {
+    const worktrees = [
+      retentionCandidate('wt-old-small', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS - 2, {
+        retainedPaneCount: 2
+      }),
+      retentionCandidate('wt-middle', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS - 1, {
+        retainedPaneCount: 3
+      }),
+      retentionCandidate('wt-new', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS, {
+        retainedPaneCount: 4
+      })
+    ]
+
+    expect(
+      selectRetentionForceParkedTerminalWorktrees({
+        ...base,
+        worktrees,
+        retentionLimit: 6
+      })
+    ).toEqual(new Set(['wt-middle']))
+  })
+
+  it('weights high-scrollback panes against the same renderer budget', () => {
+    const worktrees = [
+      retentionCandidate('wt-old', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS - 1),
+      retentionCandidate('wt-new', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS)
+    ]
+
+    expect(
+      selectRetentionForceParkedTerminalWorktrees({
+        ...base,
+        worktrees,
+        scrollbackRows: 50_000
+      })
+    ).toEqual(new Set(['wt-old']))
+  })
+
+  it('force-parks past the TTL even under the limit while retaining a newer candidate', () => {
     const worktrees = [
       retentionCandidate('wt-old', nowMs - TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS),
       retentionCandidate('wt-recent', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS)
@@ -89,10 +142,9 @@ describe('selectRetentionForceParkedTerminalWorktrees', () => {
     )
   })
 
-  // Why: the last-active exemption keeps the warm cap's "return is always instant"
-  // promise, but carrying it into the eviction clock made "none past 45 minutes"
-  // false — a lone hidden un-parkable worktree stayed mounted for the whole session.
-  it('force-parks the last-active candidate once it passes the TTL (the exemption bounds the cap, not the clock)', () => {
+  // Why: capacity never overrides the absolute clock; otherwise a lone hidden
+  // un-parkable worktree could stay mounted for the whole session.
+  it('force-parks the newest candidate once it passes the TTL', () => {
     const lone = [retentionCandidate('wt-lone', nowMs - TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS)]
     expect(selectRetentionForceParkedTerminalWorktrees({ ...base, worktrees: lone })).toEqual(
       new Set(['wt-lone'])
@@ -124,7 +176,7 @@ describe('selectRetentionForceParkedTerminalWorktrees', () => {
   // again the instant the lease ends — the remount/reattach thrash Bug #2.
   it('holds a candidate out of force-park until its post-measure cool-down ends', () => {
     const aged = nowMs - TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS
-    // Why the recent sibling: it takes the last-active exemption, so the aged
+    // Why the recent sibling: it claims the only capacity, so the aged
     // candidate's verdict is decided by the cool-down alone.
     const recent = retentionCandidate('wt-recent', nowMs - TERMINAL_WORKTREE_PARK_DELAY_MS)
     expect(
@@ -178,6 +230,77 @@ describe('selectRetentionForceParkedTerminalWorktrees', () => {
   })
 })
 
+describe('terminal hidden pane retention weight', () => {
+  it('counts split leaves, PTY-only rootless layouts, and a fresh one-pane layout', () => {
+    expect(
+      countTerminalLayoutPanes({
+        root: {
+          type: 'split',
+          direction: 'horizontal',
+          first: { type: 'leaf', leafId: 'leaf-1' },
+          second: { type: 'leaf', leafId: 'leaf-2' }
+        },
+        activeLeafId: 'leaf-1',
+        expandedLeafId: null
+      })
+    ).toBe(2)
+    expect(
+      countTerminalLayoutPanes({
+        root: null,
+        activeLeafId: null,
+        expandedLeafId: null,
+        ptyIdsByLeafId: { 'leaf-1': 'pty-1', 'leaf-2': 'pty-2', 'leaf-3': 'pty-3' }
+      })
+    ).toBe(3)
+    expect(countTerminalLayoutPanes(undefined)).toBe(1)
+  })
+
+  it('scales pane weight by configured scrollback rows', () => {
+    expect(getTerminalHiddenPaneRetentionWeight(3, 5_000)).toBe(3)
+    expect(getTerminalHiddenPaneRetentionWeight(3, 25_000)).toBe(15)
+    expect(getTerminalHiddenPaneRetentionWeight(2, 50_000)).toBe(20)
+  })
+
+  it('reuses pane counts across unrelated store writes and buffer-only layout changes', () => {
+    const root = { type: 'leaf' as const, leafId: 'leaf-1' }
+    const terminalLayoutsByTabId = {
+      'tab-1': { root, activeLeafId: 'leaf-1', expandedLeafId: null }
+    }
+    const first = selectTerminalLayoutPaneCountByTabId({ terminalLayoutsByTabId })
+
+    expect(selectTerminalLayoutPaneCountByTabId({ terminalLayoutsByTabId })).toBe(first)
+    expect(
+      selectTerminalLayoutPaneCountByTabId({
+        terminalLayoutsByTabId: {
+          'tab-1': {
+            root,
+            activeLeafId: 'leaf-1',
+            expandedLeafId: null,
+            buffersByLeafId: { 'leaf-1': 'updated buffer' }
+          }
+        }
+      })
+    ).toBe(first)
+
+    const changed = selectTerminalLayoutPaneCountByTabId({
+      terminalLayoutsByTabId: {
+        'tab-1': {
+          root: {
+            type: 'split',
+            direction: 'horizontal',
+            first: root,
+            second: { type: 'leaf', leafId: 'leaf-2' }
+          },
+          activeLeafId: 'leaf-1',
+          expandedLeafId: null
+        }
+      }
+    })
+    expect(changed).not.toBe(first)
+    expect(changed).toEqual({ 'tab-1': 2 })
+  })
+})
+
 describe('selectForceParkEvictableTabIds', () => {
   const tabs = [{ id: 'tab-exempt' }, { id: 'tab-evictable' }]
 

src/renderer/src/components/terminal-pane/terminal-hidden-worktree-retention.ts

@@ -1,33 +1,84 @@
 import { isRemoteRuntimePtyId } from '@/runtime/runtime-terminal-inspection'
 import { parseAppSshPtyId } from '../../../../shared/ssh-pty-id'
+import {
+  DESKTOP_TERMINAL_SCROLLBACK_ROWS_DEFAULT,
+  normalizeDesktopTerminalScrollbackRows
+} from '../../../../shared/terminal-scrollback-policy'
+import type { TerminalLayoutSnapshot } from '../../../../shared/types'
 import {
   TERMINAL_WORKTREE_COLD_PARK_DELAY_MS,
   isSnapshotBackedTerminalPty,
-  selectIdsBeyondHotRetain,
-  type ColdParkRetainCandidate,
   type TerminalColdParkPolicyOverrides
 } from './terminal-hidden-view-parking'
+import { collectLeafIdsInOrder } from './terminal-layout-leaf-ids'
 
 // Why these sizes: a retained hidden pane costs a measured ~2.5MB of V8 heap
 // at the 5k-row default scrollback and ~19MB at 50k (plus per-pane queues),
-// not the ~4-5MB per WORKTREE the warm cap assumed — so un-parkable worktrees
-// (pty classes parking can't restore) get a retention budget: at most 12 stay
-// mounted while hidden and none past 45 minutes, evicted least-recently-hidden
-// first via force-park. The TTL is absolute: the last-active exemption bounds
-// the cap, never the clock.
+// not the ~4-5MB per WORKTREE the warm cap assumed. Un-parkable worktrees
+// therefore share 12 default-scrollback pane units while hidden; split panes,
+// tabs, and larger scrollback all spend that budget. Newer worktrees claim
+// capacity first, candidates that do not fit force-park, and none survive past
+// 45 minutes. The newest candidate stays warm only when it fits.
 // NOT covered by this bound: eviction-exempt TABS (isEvictionExemptTerminalPty
 // — live local ptys a remount would respawn, orphaning the shell). Their panes
 // stay mounted through a force-park at any age, so a fleet-wide daemon
 // fail-open can leave the budget freeing nothing; Terminal.tsx logs that
 // degenerate case rather than pretending the bound held.
-// Also NOT covered: per-pane scrollback size. Hidden-pane scrollback demotion
-// was intentionally removed — the bound is worktree count + TTL only, so a
-// spared worktree (last-active, exempt tabs) can hold full 50k-row scrollback
-// indefinitely. Accepted tradeoff: high-scrollback users rely on unmount
-// eviction, not demotion.
-export const TERMINAL_HIDDEN_WORKTREE_RETENTION_LIMIT = 12
+// Scrollback is weighted instead of demoted: a 50k pane spends 10 units.
+export const TERMINAL_HIDDEN_PANE_RETENTION_LIMIT = 12
 export const TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS = 45 * 60_000
 
+export function countTerminalLayoutPanes(layout: TerminalLayoutSnapshot | undefined): number {
+  return Math.max(
+    1,
+    collectLeafIdsInOrder(layout?.root).length,
+    Object.keys(layout?.ptyIdsByLeafId ?? {}).length
+  )
+}
+
+type TerminalLayoutPaneCountState = {
+  terminalLayoutsByTabId: Record<string, TerminalLayoutSnapshot>
+}
+
+let cachedTerminalLayoutsByTabId: Record<string, TerminalLayoutSnapshot> | null = null
+let cachedTerminalLayoutPaneCountByTabId: Readonly<Record<string, number>> = {}
+
+export function selectTerminalLayoutPaneCountByTabId(
+  state: TerminalLayoutPaneCountState
+): Readonly<Record<string, number>> {
+  if (state.terminalLayoutsByTabId === cachedTerminalLayoutsByTabId) {
+    return cachedTerminalLayoutPaneCountByTabId
+  }
+  const next = Object.fromEntries(
+    Object.entries(state.terminalLayoutsByTabId).map(([tabId, layout]) => [
+      tabId,
+      countTerminalLayoutPanes(layout)
+    ])
+  )
+  const nextKeys = Object.keys(next)
+  if (
+    Object.keys(cachedTerminalLayoutPaneCountByTabId).length !== nextKeys.length ||
+    nextKeys.some((tabId) => cachedTerminalLayoutPaneCountByTabId[tabId] !== next[tabId])
+  ) {
+    cachedTerminalLayoutPaneCountByTabId = next
+  }
+  cachedTerminalLayoutsByTabId = state.terminalLayoutsByTabId
+  return cachedTerminalLayoutPaneCountByTabId
+}
+
+export function getTerminalHiddenPaneRetentionWeight(
+  retainedPaneCount: number,
+  scrollbackRows: unknown
+): number {
+  const paneCount =
+    Number.isFinite(retainedPaneCount) && retainedPaneCount > 0 ? Math.floor(retainedPaneCount) : 0
+  const rowWeight = Math.ceil(
+    normalizeDesktopTerminalScrollbackRows(scrollbackRows) /
+      DESKTOP_TERMINAL_SCROLLBACK_ROWS_DEFAULT
+  )
+  return paneCount * rowWeight
+}
+
 // Why: an eviction-exempt pty is a live local one a remount could not reattach
 // (daemon-fail-open separator-less ids, ptys minted under another worktree) — a
 // fresh spawn would orphan the live shell. Its TAB keeps its mounted pane when
@@ -59,21 +110,22 @@ export type TerminalWorktreeRetentionCandidate = {
   ordinaryParkingCovers: boolean
   /** Pending startup or activation spawn — a mount is imminent; never evict. */
   hasPendingSpawnWork: boolean
+  /** Mounted renderer burden represented by the persisted tab/split topology. */
+  retainedPaneCount: number
 }
 
 /**
- * Retention budget over the worktrees ordinary parking can never evict: any
- * hidden un-parkable worktree beyond the retention limit or TTL force-parks —
+ * Retention budget over the worktrees ordinary parking can never evict: hidden
+ * pane weight beyond the retention limit, or any worktree past TTL, force-parks —
  * panes unmount, watchers cover the tabs whose transport exists, and reveal
  * restores per pty class (the app-restart experience). Eviction-exempt tabs
  * do NOT veto the worktree: they keep their mounted panes via the per-tab
  * exclusion (Activity-portal pattern) while sibling tabs unmount, so one
  * exempt tab can no longer pin co-located remote-runtime tabs forever.
- * Ranking reuses the hot-retain machinery, so deterministic ties hold here too,
- * and the verdict changes only at deadlines or on real state transitions (no
- * new flip-loop inputs). The last-active exemption it carries spares one
- * worktree from the CAP only — the TTL below overrides it, else a lone hidden
- * un-parkable worktree would stay mounted for the whole session.
+ * Newest candidates claim the pane/scrollback budget first, deterministic ties
+ * break by id, and an individually-overweight newest candidate force-parks
+ * instead of defeating the bound. Older candidates may use capacity left by a
+ * newer candidate that did not fit.
  */
 export function selectRetentionForceParkedTerminalWorktrees(
   args: {
@@ -81,13 +133,20 @@ export function selectRetentionForceParkedTerminalWorktrees(
     parkingEnabled: boolean
     retentionBudgetEnabled: boolean
     nowMs: number
+    scrollbackRows?: number
   } & TerminalColdParkPolicyOverrides
 ): Set<string> {
   if (!args.parkingEnabled || !args.retentionBudgetEnabled) {
     return new Set()
   }
   const coldParkDelayMs = args.coldParkDelayMs ?? TERMINAL_WORKTREE_COLD_PARK_DELAY_MS
-  const candidates: ColdParkRetainCandidate[] = []
+  const retentionTtlMs = args.retentionTtlMs ?? TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS
+  const forceParkedIds = new Set<string>()
+  const retainedCandidates: {
+    id: string
+    hiddenSinceMs: number
+    weight: number
+  }[] = []
   for (const worktree of args.worktrees) {
     if (
       worktree.hiddenSinceMs === null ||
@@ -101,19 +160,26 @@ export function selectRetentionForceParkedTerminalWorktrees(
     ) {
       continue
     }
-    candidates.push({ id: worktree.worktreeId, hiddenSinceMs: worktree.hiddenSinceMs })
+    if (args.nowMs - worktree.hiddenSinceMs >= retentionTtlMs) {
+      forceParkedIds.add(worktree.worktreeId)
+      continue
+    }
+    retainedCandidates.push({
+      id: worktree.worktreeId,
+      hiddenSinceMs: worktree.hiddenSinceMs,
+      weight: getTerminalHiddenPaneRetentionWeight(worktree.retainedPaneCount, args.scrollbackRows)
+    })
   }
-  const retentionTtlMs = args.retentionTtlMs ?? TERMINAL_HIDDEN_WORKTREE_RETENTION_TTL_MS
-  const forceParkedIds = selectIdsBeyondHotRetain(candidates, {
-    nowMs: args.nowMs,
-    hotRetainMs: retentionTtlMs,
-    hotRetainLimit: args.retentionLimit ?? TERMINAL_HIDDEN_WORKTREE_RETENTION_LIMIT
+  retainedCandidates.sort((left, right) => {
+    const recencyDelta = right.hiddenSinceMs - left.hiddenSinceMs
+    return recencyDelta === 0 ? left.id.localeCompare(right.id) : recencyDelta
   })
-  // Why re-applied here: selectIdsBeyondHotRetain spares the last-active id from
-  // its clock too, which is right for the warm cap (instant return after a
-  // meeting) but makes "none past 45 minutes" false for a lone hidden worktree.
-  for (const candidate of candidates) {
-    if (args.nowMs - candidate.hiddenSinceMs >= retentionTtlMs) {
+  const retentionLimit = Math.max(0, args.retentionLimit ?? TERMINAL_HIDDEN_PANE_RETENTION_LIMIT)
+  let retainedWeight = 0
+  for (const candidate of retainedCandidates) {
+    if (retainedWeight + candidate.weight <= retentionLimit) {
+      retainedWeight += candidate.weight
+    } else {
       forceParkedIds.add(candidate.id)
     }
   }

src/renderer/src/components/terminal-pane/terminal-parking-e2e-overrides.ts

@@ -16,13 +16,12 @@ export function getTerminalParkingPolicyOverrides(): TerminalColdParkPolicyOverr
   const delayMs = e2eConfig.terminalParkingDelayMs
   const retentionLimit = e2eConfig.terminalRetentionLimit
   return {
-    // Why the retention TTL keeps production timing: it is absolute (the
-    // last-active exemption does not spare it), so shrinking it here would
-    // evict the newest hidden worktree the cap specs assert stays mounted.
+    // Why the retention TTL keeps production timing: it is absolute, so
+    // shrinking it here would evict the newest candidate despite fitting capacity.
     ...(typeof delayMs === 'number' && Number.isFinite(delayMs) && delayMs > 0
       ? { coldParkDelayMs: delayMs, hotRetainMs: delayMs }
       : {}),
-    // Why: limit=1 lets a spec force-park with only two hidden un-parkable worktrees (production floor is 12).
+    // Why: a one-unit override lets two one-pane worktrees exceed the test budget.
     ...(typeof retentionLimit === 'number' && Number.isInteger(retentionLimit) && retentionLimit > 0
       ? { retentionLimit }
       : {})

src/renderer/src/components/terminal-pane/terminal-shutdown-layout-capture.test.ts

@@ -2,9 +2,10 @@ import { beforeAll, beforeEach, describe, expect, it, vi } from 'vitest'
 import { TERMINAL_SCROLLBACK_SESSION_BUFFER_BYTE_LIMIT } from '../../../../shared/terminal-scrollback-limits'
 import type { TerminalLayoutSnapshot } from '../../../../shared/types'
 import { getUtf8ByteLength } from '../../../../shared/utf8-byte-limits'
+import type { TerminalLeafId } from '../../../../shared/stable-pane-id'
 
-const LEAF_ID = '11111111-1111-4111-8111-111111111111' as const
-const LEAF_ID_2 = '22222222-2222-4222-8222-222222222222' as const
+const LEAF_ID = '11111111-1111-4111-8111-111111111111' as TerminalLeafId
+const LEAF_ID_2 = '22222222-2222-4222-8222-222222222222' as TerminalLeafId
 
 // Why: capture now appends an absolute cursor restore (see
 // terminal-serialize-absolute-cursor.ts), so pane mocks must expose the
@@ -329,6 +330,87 @@ describe('captureTerminalShutdownLayout', () => {
     expect(layout.titlesByLeafId).toEqual({ [LEAF_ID]: 'local shell' })
   })
 
+  it('skips excluded remote-runtime scrollback while capturing sibling panes', async () => {
+    const { captureTerminalShutdownLayout } = await import('./terminal-shutdown-layout-capture')
+    const excludedSerialize = vi.fn(() => 'remote snapshot')
+    const capturedSerialize = vi.fn(() => 'ssh snapshot')
+    const firstPane = {
+      id: 1,
+      leafId: LEAF_ID,
+      terminal: mockTerminal(1_000),
+      serializeAddon: { serialize: excludedSerialize }
+    }
+    const secondPane = {
+      id: 2,
+      leafId: LEAF_ID_2,
+      terminal: mockTerminal(1_000),
+      serializeAddon: { serialize: capturedSerialize }
+    }
+    const manager = {
+      getPanes: vi.fn(() => [firstPane, secondPane]),
+      getActivePane: vi.fn(() => secondPane)
+    }
+
+    const layout = captureTerminalShutdownLayout({
+      manager: manager as never,
+      container: mockRootForSplit(),
+      expandedPaneId: null,
+      paneTransports: new Map([
+        [1, { getPtyId: vi.fn(() => 'remote:env-1@@terminal-1') }],
+        [2, { getPtyId: vi.fn(() => 'ssh:conn-1@@pty-2') }]
+      ]),
+      paneTitlesByPaneId: {},
+      existingLayout: {
+        root: null,
+        activeLeafId: LEAF_ID,
+        expandedLeafId: null,
+        buffersByLeafId: {
+          [LEAF_ID]: 'prior remote snapshot',
+          [LEAF_ID_2]: 'prior ssh snapshot'
+        },
+        scrollbackRefsByLeafId: {
+          [LEAF_ID]: 'remote-ref',
+          [LEAF_ID_2]: 'ssh-ref'
+        }
+      },
+      excludedScrollbackLeafIds: new Set([LEAF_ID])
+    })
+
+    expect(excludedSerialize).not.toHaveBeenCalled()
+    expect(capturedSerialize).toHaveBeenCalledOnce()
+    expect(layout.buffersByLeafId).toEqual({
+      [LEAF_ID_2]: `ssh snapshot${CURSOR_HOME}`
+    })
+    expect(layout.scrollbackRefsByLeafId).toEqual({ [LEAF_ID_2]: 'ssh-ref' })
+  })
+
+  it('uses the persisted pty binding to exclude a remote-runtime pane during attach', async () => {
+    const { selectRemoteRuntimeScrollbackLeafIds } =
+      await import('./terminal-shutdown-layout-capture')
+    const panes = [
+      { id: 1, leafId: LEAF_ID },
+      { id: 2, leafId: LEAF_ID_2 }
+    ]
+    const excluded = selectRemoteRuntimeScrollbackLeafIds({
+      panes,
+      paneTransports: new Map([
+        [1, { getPtyId: () => null }],
+        [2, { getPtyId: () => 'repo::/worktree@@live-local' }]
+      ]),
+      existingLayout: {
+        root: null,
+        activeLeafId: LEAF_ID,
+        expandedLeafId: null,
+        ptyIdsByLeafId: {
+          [LEAF_ID]: 'remote:env-1@@terminal-1',
+          [LEAF_ID_2]: 'remote:stale-env@@terminal-2'
+        }
+      }
+    })
+
+    expect(excluded).toEqual(new Set([LEAF_ID]))
+  })
+
   it('does not preserve stale prior PTY bindings as shutdown focus targets', async () => {
     const { captureTerminalShutdownLayout } = await import('./terminal-shutdown-layout-capture')
     const deadPane = {

src/renderer/src/components/terminal-pane/terminal-shutdown-layout-capture.ts

@@ -8,6 +8,7 @@ import { resolveTerminalLayoutActiveLeafId } from './terminal-layout-leaf-ids'
 import { TERMINAL_SCROLLBACK_SESSION_BUFFER_BYTE_LIMIT } from '../../../../shared/terminal-scrollback-limits'
 import { serializeWithAbsoluteCursor } from '../../../../shared/terminal-serialize-absolute-cursor'
 import { getUtf8ByteLength, measureUtf8ByteLength } from '../../../../shared/utf8-byte-limits'
+import { isRemoteRuntimePtyId } from '@/runtime/runtime-terminal-inspection'
 
 const MAX_BUFFER_BYTES = TERMINAL_SCROLLBACK_SESSION_BUFFER_BYTE_LIMIT
 
@@ -18,6 +19,23 @@ type ShutdownPaneManager = {
   getActivePane(): ShutdownPane | null
 }
 
+export function selectRemoteRuntimeScrollbackLeafIds(args: {
+  panes: readonly Pick<ShutdownPane, 'id' | 'leafId'>[]
+  paneTransports: ReadonlyMap<number, Pick<PtyTransport, 'getPtyId'>>
+  existingLayout: TerminalLayoutSnapshot | undefined
+}): Set<string> {
+  const excludedLeafIds = new Set<string>()
+  for (const pane of args.panes) {
+    const livePtyId = args.paneTransports.get(pane.id)?.getPtyId()
+    // The persisted binding covers the attach gap before transport reports its PTY.
+    const ptyId = livePtyId ?? args.existingLayout?.ptyIdsByLeafId?.[pane.leafId] ?? null
+    if (ptyId && isRemoteRuntimePtyId(ptyId)) {
+      excludedLeafIds.add(pane.leafId)
+    }
+  }
+  return excludedLeafIds
+}
+
 type CaptureTerminalShutdownLayoutArgs = {
   manager: ShutdownPaneManager
   container: HTMLDivElement
@@ -27,6 +45,7 @@ type CaptureTerminalShutdownLayoutArgs = {
   existingLayout: TerminalLayoutSnapshot | undefined
   captureBuffers?: boolean
   clearedScrollbackLeafIds?: ReadonlySet<string>
+  excludedScrollbackLeafIds?: ReadonlySet<string>
 }
 
 function omitClearedLeafState(
@@ -97,13 +116,17 @@ export function captureTerminalShutdownLayout({
   paneTitlesByPaneId,
   existingLayout,
   captureBuffers = true,
-  clearedScrollbackLeafIds
+  clearedScrollbackLeafIds,
+  excludedScrollbackLeafIds
 }: CaptureTerminalShutdownLayoutArgs): TerminalLayoutSnapshot {
   const panes = manager.getPanes()
   const buffers: Record<string, string> = {}
 
   if (captureBuffers) {
     for (const pane of panes) {
+      if (excludedScrollbackLeafIds?.has(pane.leafId)) {
+        continue
+      }
       try {
         // Why: non-focused panes may have renderer-throttled PTY bytes queued;
         // push them into xterm before taking the shutdown scrollback snapshot.
@@ -138,6 +161,10 @@ export function captureTerminalShutdownLayout({
     new Map(panes.map((pane) => [pane.id, pane.leafId]))
   )
   const currentLeafIds = new Set(panes.map((p) => p.leafId))
+  const omittedScrollbackLeafIds = new Set([
+    ...(clearedScrollbackLeafIds ?? []),
+    ...(excludedScrollbackLeafIds ?? [])
+  ])
   const livePtyIdsByLeafId: Record<string, string> = {}
   const preservedPtyIdsByLeafId: Record<string, string> = {}
   for (const pane of panes) {
@@ -157,13 +184,13 @@ export function captureTerminalShutdownLayout({
 
   const mergedBuffers = captureBuffers
     ? mergeCapturedLeafState({
-        prior: omitClearedLeafState(existingLayout?.buffersByLeafId, clearedScrollbackLeafIds),
+        prior: omitClearedLeafState(existingLayout?.buffersByLeafId, omittedScrollbackLeafIds),
         fresh: buffers,
         currentLeafIds
       })
     : {}
   const mergedScrollbackRefs = mergeCapturedLeafState({
-    prior: omitClearedLeafState(existingLayout?.scrollbackRefsByLeafId, clearedScrollbackLeafIds),
+    prior: omitClearedLeafState(existingLayout?.scrollbackRefsByLeafId, omittedScrollbackLeafIds),
     fresh: {},
     currentLeafIds
   })

src/renderer/src/components/terminal-pane/terminal-side-effect-facts-handler.test.ts

@@ -484,6 +484,45 @@ describe('registerTerminalSideEffectFactConsumer', () => {
     expect(later).toEqual([])
   })
 
+  it('keeps attention facts through title churn that exceeds the handoff cap', () => {
+    const dispose = registerTerminalSideEffectFactConsumer({
+      ptyId: PTY_ID,
+      callbacks: createCallbackRecorder().callbacks
+    })
+    dispose()
+    _dispatchTerminalSideEffectBatchForTest(
+      batch([{ kind: 'bell' }, { kind: 'command-code-done', prompt: 'Ship it' }], { seq: 1 })
+    )
+    for (let seq = 2; seq <= 130; seq += 1) {
+      _dispatchTerminalSideEffectBatchForTest(
+        batch(
+          [
+            {
+              kind: 'title',
+              normalizedTitle: `Codex frame ${seq}`,
+              rawTitle: `Codex frame ${seq}`
+            }
+          ],
+          { seq }
+        )
+      )
+    }
+
+    const events: unknown[][] = []
+    registerTerminalSideEffectFactConsumer({
+      ptyId: PTY_ID,
+      callbacks: {
+        onBell: () => events.push(['bell']),
+        onCommandCodeDone: (prompt) => events.push(['cc-done', prompt]),
+        onTitleChange: (title) => events.push(['title', title])
+      }
+    })
+
+    expect(events).toContainEqual(['bell'])
+    expect(events).toContainEqual(['cc-done', 'Ship it'])
+    expect(events.at(-1)).toEqual(['title', 'Codex frame 130'])
+  })
+
   it('does not buffer replay batches across a handoff', () => {
     // Why: the next consumer requests its own snapshot; a held replay would
     // regress the title it just restored.
@@ -538,7 +577,7 @@ describe('registerTerminalSideEffectFactConsumer', () => {
     expect(events).toEqual([['title', 'live', 'live']])
   })
 
-  it('drops a handoff-buffered batch once the buffer TTL expires', () => {
+  it('keeps handoff facts through relay and SSH retry settlement, then expires them', () => {
     vi.useFakeTimers()
     try {
       const dispose = registerTerminalSideEffectFactConsumer({
@@ -548,12 +587,21 @@ describe('registerTerminalSideEffectFactConsumer', () => {
       dispose()
       _dispatchTerminalSideEffectBatchForTest(batch([{ kind: 'bell' }]))
 
-      vi.advanceTimersByTime(15_001)
+      vi.advanceTimersByTime(61_001)
 
       const { callbacks, events } = createCallbackRecorder()
-      registerTerminalSideEffectFactConsumer({ ptyId: PTY_ID, callbacks })
+      const disposeAfterRetry = registerTerminalSideEffectFactConsumer({ ptyId: PTY_ID, callbacks })
 
-      expect(events).toEqual([])
+      expect(events).toEqual([['bell']])
+
+      disposeAfterRetry()
+      _dispatchTerminalSideEffectBatchForTest(batch([{ kind: 'bell' }]))
+      vi.advanceTimersByTime(75_001)
+
+      const expired = createCallbackRecorder()
+      registerTerminalSideEffectFactConsumer({ ptyId: PTY_ID, callbacks: expired.callbacks })
+
+      expect(expired.events).toEqual([])
     } finally {
       vi.useRealTimers()
     }

src/renderer/src/components/terminal-pane/terminal-side-effect-facts-handler.ts

@@ -173,7 +173,9 @@ function applyBatchToConsumer(entry: ConsumerEntry, batch: TerminalSideEffectBat
 // dropped in that window is lost for good. Only a PTY that just lost its
 // consumer buffers (never-consumed PTYs still drop, per the module contract),
 // bounded in time, batches, and PTYs so an abandoned handoff retains nothing.
-const HANDOFF_FACT_BUFFER_TTL_MS = 15_000
+// Why 75s: a reveal can traverse a 30s relay request and 31s direct-pane
+// settlement before registration; keep scheduling margin beyond that chain.
+const HANDOFF_FACT_BUFFER_TTL_MS = 75_000
 const MAX_HANDOFF_FACT_BATCHES = 64
 const MAX_HANDOFF_FACT_PTYS = 32
 
@@ -215,8 +217,15 @@ function bufferHandoffFactBatch(batch: TerminalSideEffectBatch): void {
   if (batch.replay) {
     return
   }
-  if (buffer.batches.length >= MAX_HANDOFF_FACT_BATCHES) {
-    buffer.batches.shift()
+  const isTitleOnly = (candidate: TerminalSideEffectBatch): boolean =>
+    candidate.facts.every((fact) => fact.kind === 'title')
+  if (isTitleOnly(batch)) {
+    // Why: title state is last-wins; compact spinner frames so they cannot evict attention facts.
+    buffer.batches = buffer.batches.filter((candidate) => !isTitleOnly(candidate))
+  }
+  while (buffer.batches.length >= MAX_HANDOFF_FACT_BATCHES) {
+    const titleOnlyIndex = buffer.batches.findIndex(isTitleOnly)
+    buffer.batches.splice(Math.max(titleOnlyIndex, 0), 1)
   }
   buffer.batches.push(batch)
 }

src/shared/e2e-config.ts

@@ -29,7 +29,7 @@ export function createE2EConfig(input: E2EConfigInput): E2EConfig {
     input.terminalParkingDelayMs > 0
       ? input.terminalParkingDelayMs
       : null
-  // Why: a worktree count — only a positive integer is a meaningful budget.
+  // Why: pane-weight units — only a positive integer is a meaningful budget.
   const terminalRetentionLimit =
     typeof input.terminalRetentionLimit === 'number' &&
     Number.isInteger(input.terminalRetentionLimit) &&

src/shared/types.ts

@@ -2857,7 +2857,7 @@ export type GlobalSettings = {
   terminalHiddenViewParking?: boolean
   /** Kill switch for SSH terminal parking (C1): SSH panes park like local ones; reveal restores from main's headless model, falling back to relay replay. */
   terminalSshViewParking?: boolean
-  /** Kill switch for the hidden-worktree retention budget (C1): force-parks the least-recently-hidden un-parkable worktrees beyond a count budget or TTL. */
+  /** Kill switch for the hidden-worktree retention budget (C1): force-parks un-parkable worktrees beyond a pane-weight budget or TTL. */
   terminalHiddenWorktreeRetentionBudget?: boolean
   /** Kill switch for main-process PTY side-effect authority; on (default) = title/bell/agent facts via pty:sideEffect channel, not renderer byte parsing. */
   terminalMainSideEffectAuthority?: boolean

tests/e2e/terminal-parked-memory.spec.ts

@@ -17,6 +17,7 @@ import {
   waitForActiveTerminalManager,
   waitForPaneIdentitySnapshot
 } from './helpers/terminal'
+import { DESKTOP_TERMINAL_SCROLLBACK_ROWS_DEFAULT } from '../../src/shared/terminal-scrollback-policy'
 
 // Why: production cold-park hysteresis is 30s. The fast-park env override is
 // scoped to this spec's app launches via orcaAppExtraEnv (same pattern as
@@ -394,6 +395,9 @@ test.describe('Terminal parked memory', () => {
 const RETENTION_TAB_COUNT = 4
 const RETENTION_FILL_LINE_COUNT = 12_000
 const RETENTION_SCROLLBACK_ROWS = 25_000
+const RETENTION_PANE_WEIGHT = Math.ceil(
+  RETENTION_SCROLLBACK_ROWS / DESKTOP_TERMINAL_SCROLLBACK_ROWS_DEFAULT
+)
 // Why 12: xterm packs each cell as 3 uint32s in the BufferLine typed array.
 const XTERM_BYTES_PER_CELL = 12
 // Why 40: this staging measures ~87 MB of retained buffer, so half of that is a
@@ -597,12 +601,8 @@ test.describe('Terminal hidden worktree retention budget', () => {
   test.use({
     orcaAppExtraEnv: {
       ORCA_E2E_TERMINAL_PARKING_DELAY_MS: String(PARKING_DELAY_MS),
-      // Why limit=1: the retention TTL is absolute production timing (45min) and
-      // the parking-delay override deliberately no longer shrinks it, so the
-      // COUNT CAP is the only knob a test can drive. With a budget of 1 the
-      // newest hidden un-parkable worktree takes the last-active exemption and
-      // the older one force-parks — cap and exemption proven in one run.
-      ORCA_E2E_TERMINAL_RETENTION_LIMIT: '1'
+      // The newer one-pane decoy exactly fits; the four-pane victim does not.
+      ORCA_E2E_TERMINAL_RETENTION_LIMIT: String(RETENTION_PANE_WEIGHT)
     },
     orcaAppExtraArgs: ['--enable-precise-memory-info']
   })
@@ -666,8 +666,7 @@ test.describe('Terminal hidden worktree retention budget', () => {
         await stageUnparkableWorktreeTabs(orcaPage, victimWorktreeId)
       }
 
-      // Hiding the victim first makes the decoy the more-recently-hidden
-      // candidate, so the cap's last-active exemption lands on the decoy.
+      // Hiding the victim first lets the newer decoy claim the weighted budget.
       await switchToWorktree(orcaPage, decoyWorktreeId)
       await expect
         .poll(() => orcaPage.evaluate(() => window.__store?.getState().activeWorktreeId), {
@@ -761,8 +760,7 @@ test.describe('Terminal hidden worktree retention budget', () => {
 
       // Primary gate: the staged buffers are gone, not merely hidden.
       expect(after.buffers.cells).toBeLessThan(before.buffers.cells * MAX_RETAINED_CELL_FRACTION)
-      // The decoy holds the cap's last-active exemption, so it stays mounted —
-      // this is the same run proving the cap did not simply evict everything.
+      // The newer decoy fits the budget, proving the cap did not evict everything.
       expect(await countMountedPaneManagers(orcaPage, decoyTabIds)).toBe(decoyTabIds.length)
       // Secondary only: freed typed arrays return to the allocator's free lists,
       // not the OS, so RSS fell just 0.7-3.0 MB locally while 87 MB of buffer was

tests/e2e/terminal-retention-budget.spec.ts

@@ -25,8 +25,7 @@ test.use({
   seedTestRepo: false,
   orcaAppExtraEnv: {
     ORCA_E2E_TERMINAL_PARKING_DELAY_MS: String(PARKING_DELAY_MS),
-    // Why limit=1: two hidden un-parkable worktrees then exceed the budget while
-    // the last-active exemption still spares exactly one — the smallest live proof.
+    // Two one-pane worktrees exceed this one-unit test budget.
     ORCA_E2E_TERMINAL_RETENTION_LIMIT: '1'
   }
 })
@@ -66,6 +65,19 @@ test.describe('terminal hidden-worktree retention budget', () => {
           message: 'older worktree marker did not render before hiding'
         })
         .toContain(`${olderMarker}:`)
+      // Push the marker outside the relay's 100KiB tail while retaining it in
+      // the force-park capture.
+      await sendToTerminal(
+        orcaPage,
+        olderPtyId,
+        `for i in $(seq 1 3000); do echo "RETENTION_PAD_$i:0123456789012345678901234567890123456789"; done; echo "${olderMarker}_PAD_DONE:"\r`
+      )
+      await expect
+        .poll(() => getTerminalContent(orcaPage, 20_000), {
+          timeout: 60_000,
+          message: 'retention pad output did not finish before hiding'
+        })
+        .toContain(`${olderMarker}_PAD_DONE:`)
 
       // Why: with SSH view parking off, SSH ptys are not park-restorable, so the
       // hidden remote worktrees join the un-parkable class the budget governs.
@@ -110,15 +122,15 @@ test.describe('terminal hidden-worktree retention budget', () => {
 
       // The older worktree must force-park (its pane managers unmount)…
       await waitForTabParked(orcaPage, olderTabId, { parkDelayMs: PARKING_DELAY_MS })
-      // …while the newest hidden worktree keeps its mounted panes (last-active exemption).
+      // …while the newest hidden worktree claims the one-pane retention capacity.
       const newerStillMounted = await orcaPage.evaluate(
         (tabId) => window.__paneManagers?.get(tabId) !== undefined,
         newerTabId
       )
       expect(newerStillMounted).toBe(true)
 
-      // Reveal the evicted worktree: with SSH parking disabled the model paint is
-      // off, so the relay replay must restore the marker tail — never a blank pane.
+      // SSH model restore is disabled, so deep history must survive through the
+      // force-park capture while the relay tail repaints the viewport.
       await orcaPage.evaluate(
         ({ worktreeId, tabId }) => {
           const state = window.__store?.getState()
@@ -130,9 +142,9 @@ test.describe('terminal hidden-worktree retention budget', () => {
       )
       await waitForActiveTerminalManager(orcaPage, 60_000)
       await expect
-        .poll(() => getTerminalContent(orcaPage, 20_000), {
+        .poll(() => getTerminalContent(orcaPage, 2_000_000), {
           timeout: 60_000,
-          message: 'revealed evicted worktree did not restore the marker via relay replay'
+          message: 'revealed evicted worktree lost captured history beyond the relay tail'
         })
         .toContain(`${olderMarker}:`)
     } finally {