fix(renderer): terminal input tracking, workspace/session safety, panel correctness

- terminal: drop the diffRewriteRef echo assumption (Tab-accept corrupted
  history and cwd tracking), handle readline control keys in the line
  buffer, clamp degenerate PTY sizes, live copyOnSelect, bound highlight
  regex input, wide-char-safe link ranges
- workspace: boot-restore try/finally (a failure used to disable snapshot
  saving for the whole run), connect re-entrancy guard + real error
  messages, broadcast registry keyed by panel id (split panes), tab
  close-others/right live-array fix, pointer-captured bottom-panel drag,
  dockview constants hoisted, hydrate-gated restore
- panels: no chmod 000 on unknown mode, chown keeps current gid, 12-bit
  special-permission round trip, overwrite confirm, redraw monitor
  charts, gate polling on visibility, no secret carry-over between
  connections, settings sent as minimal patches, update-state pull
- language applies on the first render; accent fg recomputed on theme
  switch; window.api is properly typed again (env.d.ts import path)

src/renderer/src/App.tsx

@@ -1,4 +1,4 @@
-import { useEffect, useState } from 'react'
+import { useEffect, useState, useSyncExternalStore } from 'react'
 import { ConfigProvider } from 'antd'
 import zhCN from 'antd/locale/zh_CN'
 import zhTW from 'antd/locale/zh_TW'
@@ -9,7 +9,7 @@ import { SettingsDialog } from '@renderer/settings/SettingsDialog'
 import { TransferPanel } from '@renderer/sftp/TransferPanel'
 import { useSettingsStore } from '@renderer/settings/store'
 import { getThemeById } from '@shared/theme'
-import { DEFAULT_LANGUAGE, setLanguage, type Language } from '@shared/i18n'
+import { DEFAULT_LANGUAGE, getLanguage, onLanguageChange, setLanguage, type Language } from '@shared/i18n'
 import { applyChromeTheme, applyTabAccent } from '@renderer/theme/chrome'
 import appIconUrl from '../../../build/icon.png'
 
@@ -42,16 +42,20 @@ export default function App(): React.JSX.Element {
   const themeId = useSettingsStore((s) => s.settings.terminal.themeId)
   const customThemes = useSettingsStore((s) => s.settings.customThemes)
   const tabAccentColor = useSettingsStore((s) => s.settings.terminal.tabAccentColor)
-  const language = useSettingsStore((s) => s.settings.system.language ?? DEFAULT_LANGUAGE)
+  const storedLanguage = useSettingsStore((s) => s.settings.system.language ?? DEFAULT_LANGUAGE)
   const [settingsOpen, setSettingsOpen] = useState(false)
 
   useEffect(() => {
     void hydrate()
   }, [hydrate])
 
-  // Interface language: drives t() and antd's built-in component texts.
+  // Interface language: t() reads the module-level language at render time, so
+  // sync it before the tree renders — an effect would paint one frame late. The
+  // subscription re-renders every t() caller when the language changes elsewhere.
+  if (getLanguage() !== storedLanguage) setLanguage(storedLanguage)
+  const language = useSyncExternalStore(onLanguageChange, getLanguage)
   useEffect(() => {
-    setLanguage(language)
+    document.documentElement.lang = language
   }, [language])
 
   // Sidebar / tab bars / dividers follow the active terminal theme.

src/renderer/src/commands/CommandsPanel.tsx

@@ -260,6 +260,9 @@ function Row({
             icon={<DeleteOutlined />}
             className="commands-row-del"
             aria-label={t('panels.commands.deleteAria')}
+            // The row itself runs the command — opening the confirm must not
+            // leak that click, or the command is typed into the live terminal.
+            onClick={(e) => e.stopPropagation()}
           />
         </Popconfirm>
       )}

src/renderer/src/connections/ConnectionEditDialog.tsx

@@ -61,6 +61,11 @@ export function ConnectionEditDialog({
     setErrorMsg(null)
     const base: SshAuthMethod = editing?.auth ?? 'password'
     setAuth(base)
+    // Fields keep their value when unmounted (rc-form preserve: true), so the
+    // secrets below must be cleared explicitly — otherwise a password typed for
+    // connection A survives into connection B's save. resetFields() drops every
+    // stored value; setFieldsValue() then re-seeds the non-secret fields.
+    form.resetFields()
     form.setFieldsValue({
       name: editing?.name,
       group: editing?.group,

src/renderer/src/connections/ConnectionSidebar.tsx

@@ -85,13 +85,10 @@ export const ConnectionSidebar = forwardRef<ConnectionSidebarHandle, ConnectionS
       void refresh()
     }, [])
 
-    // Fold every group open whenever the dataset changes.
+    // Fold every group open by default; only the user's collapses are stored,
+    // so a group that appears later starts open as well.
     const defaultGroup = t('ssh.sidebar.defaultGroup')
-    const activeGroups = useMemo(() => {
-      const groups = new Set<string>()
-      for (const c of connections) groups.add(c.group ?? defaultGroup)
-      return [...groups]
-    }, [connections, defaultGroup])
+    const [closedGroups, setClosedGroups] = useState<string[]>([])
 
     const groups = useMemo(() => {
       const map = new Map<string, SshConnection[]>()
@@ -223,8 +220,10 @@ export const ConnectionSidebar = forwardRef<ConnectionSidebarHandle, ConnectionS
               ghost
               className="connections-collapse"
               items={collapseItems}
-              defaultActiveKey={groups.map((g) => g.group)}
-              activeKey={activeGroups}
+              activeKey={groups.map((g) => g.group).filter((key) => !closedGroups.includes(key))}
+              onChange={(keys) =>
+                setClosedGroups(groups.map((g) => g.group).filter((key) => !keys.includes(key)))
+              }
             />
           )}
 

src/renderer/src/env.d.ts

@@ -1,6 +1,6 @@
 /// <reference types="vite/client" />
 
-import type { AppApi } from '../shared/api'
+import type { AppApi } from '@shared/api'
 
 declare global {
   interface Window {

src/renderer/src/main.tsx

@@ -81,7 +81,7 @@ if (typeof window !== 'undefined' && !window.api) {
     onHostKeyPrompt: () => noop,
     respondHostKey: noop,
     getSettings: async () => DEFAULT_SETTINGS,
-    saveSettings: async (s) => s,
+    saveSettings: async (s) => ({ ...DEFAULT_SETTINGS, ...s }),
     onSettingsChanged: () => noop,
     listFonts: async () => [],
     listLayouts: async () => [],
@@ -89,6 +89,7 @@ if (typeof window !== 'undefined' && !window.api) {
     saveLayout: async () => undefined,
     deleteLayout: async () => undefined,
     updateCheck: async () => ({ status: 'dev' as const, currentVersion: 'dev' }),
+    getUpdateState: async () => ({ status: 'dev' as const, currentVersion: 'dev' }),
     updateDownload: async () => undefined,
     updateInstall: async () => undefined,
     updateChangelog: async () => [],

src/renderer/src/monitor/MonitorPanel.tsx

@@ -1,6 +1,7 @@
 import { useEffect, useRef, useState } from 'react'
 import type { SysinfoMeta, SysinfoSample } from '@shared/sysinfo'
 import { t } from '@shared/i18n'
+import { useWorkspaceModeStore } from '../workspace/workspaceModeStore'
 import './monitor.css'
 
 export interface MonitorPanelProps {
@@ -25,8 +26,6 @@ interface HistoryChartProps {
 function HistoryChart({ data, lineColor, fillColor, height, maxY }: HistoryChartProps): React.JSX.Element {
   const containerRef = useRef<HTMLDivElement | null>(null)
   const canvasRef = useRef<HTMLCanvasElement | null>(null)
-  const dataRef = useRef<number[]>(data)
-  dataRef.current = data
 
   useEffect(() => {
     const container = containerRef.current
@@ -45,7 +44,7 @@ function HistoryChart({ data, lineColor, fillColor, height, maxY }: HistoryChart
       ctx.setTransform(dpr, 0, 0, dpr, 0, 0)
       ctx.clearRect(0, 0, width, height)
 
-      const pts = dataRef.current
+      const pts = data
       if (pts.length < 2) return
 
       const top = maxY ?? Math.max(1, Math.max(...pts) * 1.2)
@@ -81,7 +80,9 @@ function HistoryChart({ data, lineColor, fillColor, height, maxY }: HistoryChart
     const ro = new ResizeObserver(draw)
     ro.observe(container)
     return () => ro.disconnect()
-  }, [height, maxY, lineColor, fillColor])
+    // `data` is a dep on purpose: without it the chart only ever drew at mount,
+    // when the history is still empty, and the sparklines never updated.
+  }, [data, height, maxY, lineColor, fillColor])
 
   return (
     <div ref={containerRef} className="mm-chart">
@@ -134,8 +135,12 @@ export function MonitorPanel({ sessionId }: MonitorPanelProps): React.JSX.Elemen
   const [cpuHist, setCpuHist] = useState<number[]>([])
   const [rxHist, setRxHist] = useState<number[]>([])
   const [txHist, setTxHist] = useState<number[]>([])
+  /** Switching workspace mode only hides the dockview (panels stay mounted), so
+   *  polling has to stop explicitly while the SSH workspace is not visible. */
+  const workspaceMode = useWorkspaceModeStore((s) => s.mode)
 
   useEffect(() => {
+    if (workspaceMode !== 'ssh') return
     let disposed = false
     setCpuHist([])
     setRxHist([])
@@ -161,7 +166,7 @@ export function MonitorPanel({ sessionId }: MonitorPanelProps): React.JSX.Elemen
       offSample()
       window.api.sysinfoStop(sessionId)
     }
-  }, [sessionId])
+  }, [sessionId, workspaceMode])
 
   if (!meta || !sample) {
     return (

src/renderer/src/settings/AboutTab.tsx

@@ -74,6 +74,12 @@ export function AboutTab(): React.JSX.Element {
 
   useEffect(() => {
     void window.api.appInfo().then((i: AppInfo) => setVersion(i.appVersion))
+    // Pull the updater's current state (no network check); the check itself
+    // stays behind the manual button and the auto-check-on-launch setting.
+    void window.api
+      .getUpdateState()
+      .then(setState)
+      .catch(() => undefined)
     return window.api.onUpdateState(setState)
   }, [])
 

src/renderer/src/settings/HighlightTab.tsx

@@ -25,6 +25,17 @@ const PRESET_COLORS = ['#3fb950', '#f85149', '#e3b341', '#58a6ff', '#d2a8ff', '#
 /** clone the builtin preset set to prevent reference pollution by mutations. */
 const cloneDefaults = (): HighlightRule[] => JSON.parse(JSON.stringify(DEFAULT_HIGHLIGHT_RULES)) as HighlightRule[]
 
+/**
+ * Built-in rule notes are stored as zh-CN presets; the dictionaries carry a
+ * `settings.highlight.builtin.<id>` entry per built-in id. `t()` returns the key
+ * itself when it is missing, so fall back to the stored note in that case.
+ */
+function ruleNote(rule: HighlightRule): string | undefined {
+  const key = `settings.highlight.builtin.${rule.id}`
+  const translated = t(key)
+  return translated === key ? rule.note : translated
+}
+
 function tryCompile(pattern: string): { ok: boolean; message?: string } {
   if (pattern.trim() === '') return { ok: true }
   try {
@@ -128,8 +139,10 @@ export function HighlightTab(): React.JSX.Element {
       title: t('settings.highlight.note'),
       dataIndex: 'note',
       ellipsis: true,
-      render: (note: string | undefined) =>
-        note ? <span className="hl-cell-note">{note}</span> : <span className="hl-cell-empty">—</span>
+      render: (_note: string | undefined, record) => {
+        const note = ruleNote(record)
+        return note ? <span className="hl-cell-note">{note}</span> : <span className="hl-cell-empty">—</span>
+      }
     },
     {
       title: t('settings.highlight.actions'),

src/renderer/src/settings/SettingsDialog.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useMemo, useState } from 'react'
-import { Button, Modal, Tabs } from 'antd'
+import { Button, Modal, Popconfirm, Tabs } from 'antd'
 import type { TabsProps } from 'antd'
 import { t } from '@shared/i18n'
 import { DEFAULT_SETTINGS } from '@shared/settings'
@@ -11,6 +11,12 @@ import { AboutTab } from './AboutTab'
 import { ThemeEditor } from '../theme/editor/ThemeEditor'
 import './settings.css'
 
+/** t() falls back to the key itself when a translation is missing. */
+function tOr(key: string, fallback: string): string {
+  const value = t(key)
+  return value === key ? fallback : value
+}
+
 export interface SettingsDialogProps {
   open: boolean
   onClose: () => void
@@ -94,6 +100,10 @@ export function SettingsDialog({ open, onClose }: SettingsDialogProps): React.JS
     void updateTerminal({ ...DEFAULT_SETTINGS.terminal })
   }
 
+  // Reset touches the whole terminal group, so it asks first and says so.
+  const resetLabel = tOr('settings.resetTerminal', t('common.reset'))
+  const resetDesc = tOr('settings.resetTerminalDesc', '')
+
   return (
     <Modal
       open={open}
@@ -103,7 +113,16 @@ export function SettingsDialog({ open, onClose }: SettingsDialogProps): React.JS
       title={t('settings.title')}
       footer={
         <div className="settings-footer">
-          <Button onClick={handleResetDefaults}>{t('common.reset')}</Button>
+          <Popconfirm
+            title={tOr('settings.resetTerminalTitle', t('common.reset'))}
+            description={resetDesc || undefined}
+            okText={resetLabel}
+            cancelText={t('common.cancel')}
+            okButtonProps={{ danger: true }}
+            onConfirm={handleResetDefaults}
+          >
+            <Button>{resetLabel}</Button>
+          </Popconfirm>
           <Button type="primary" onClick={onClose}>
             {t('common.close')}
           </Button>

src/renderer/src/settings/SettingsTabs.tsx

@@ -357,6 +357,8 @@ export function RenderSettingsTab(): React.JSX.Element {
 export function SystemSettingsTab(): React.JSX.Element {
   const settings = useSettingsStore((s) => s.settings)
   const updateSystem = useSettingsStore((s) => s.updateSystem)
+  /** set when the recorder refused a combo reserved by an in-app shortcut */
+  const [shortcutConflict, setShortcutConflict] = useState(false)
   return (
     <div className="settings-pane">
       {/* Interface language — first row: the whole dialog re-renders on change. */}
@@ -433,11 +435,14 @@ export function SystemSettingsTab(): React.JSX.Element {
           <ShortcutInput
             value={settings.system.globalShowHide ?? ''}
             onChange={(v) => void updateSystem({ globalShowHide: v })}
+            onConflict={setShortcutConflict}
           />
         }
       />
       <div className="settings-block-hint settings-shortcut-hint">
-        {t('settings.system.globalShortcutHint')}
+        {shortcutConflict
+          ? tOr('settings.system.shortcutConflict', t('settings.system.globalShortcutHint'))
+          : t('settings.system.globalShortcutHint')}
       </div>
     </div>
   )
@@ -486,12 +491,43 @@ function acceleratorFromEvent(e: React.KeyboardEvent<HTMLInputElement>): string
   return parts.join('+')
 }
 
+/**
+ * Keys this app binds while Control is held: font size (Ctrl+=/-/0, main.tsx)
+ * and tab cycling (Ctrl+PgUp/PgDn, Workspace). Neither handler looks at the
+ * other modifiers, so any Control combo on one of these keys would shadow the
+ * in-app action — the recorder refuses it instead of saving a shortcut that
+ * silently loses its original meaning.
+ */
+const RESERVED_CONTROL_KEYS = new Set(['=', '-', '0', 'PageUp', 'PageDown'])
+
+/** true when `accel` (e.g. "Control+Shift+=") collides with an in-app shortcut */
+function isReservedAccelerator(accel: string): boolean {
+  const parts = accel.split('+')
+  return parts.includes('Control') && RESERVED_CONTROL_KEYS.has(parts[parts.length - 1])
+}
+
+/** t() falls back to the key itself when a translation is missing. */
+function tOr(key: string, fallback: string): string {
+  const value = t(key)
+  return value === key ? fallback : value
+}
+
 /**
  * Press-to-record input for the global shortcut: focus it, hit the combo, the
  * accelerator is captured and saved. Esc cancels recording, Backspace/Delete
  * clears (disables) the shortcut. Read-only so no stray text can be typed.
+ * A combo reserved by an in-app shortcut is refused (and reported through
+ * `onConflict`) without leaving the recording state, so the user can retry.
  */
-function ShortcutInput({ value, onChange }: { value: string; onChange: (v: string) => void }): React.JSX.Element {
+function ShortcutInput({
+  value,
+  onChange,
+  onConflict
+}: {
+  value: string
+  onChange: (v: string) => void
+  onConflict: (conflict: boolean) => void
+}): React.JSX.Element {
   const [recording, setRecording] = useState(false)
   return (
     <Input
@@ -499,8 +535,14 @@ function ShortcutInput({ value, onChange }: { value: string; onChange: (v: strin
       readOnly
       value={recording ? t('settings.system.shortcutRecording') : value}
       placeholder={t('settings.system.shortcutPlaceholder')}
-      onFocus={() => setRecording(true)}
-      onBlur={() => setRecording(false)}
+      onFocus={() => {
+        setRecording(true)
+        onConflict(false)
+      }}
+      onBlur={() => {
+        setRecording(false)
+        onConflict(false)
+      }}
       onKeyDown={(e) => {
         e.preventDefault()
         e.stopPropagation()
@@ -514,10 +556,14 @@ function ShortcutInput({ value, onChange }: { value: string; onChange: (v: strin
           return
         }
         const accel = acceleratorFromEvent(e)
-        if (accel) {
-          onChange(accel)
-          e.currentTarget.blur()
+        if (!accel) return
+        if (isReservedAccelerator(accel)) {
+          onConflict(true)
+          return
         }
+        onConflict(false)
+        onChange(accel)
+        e.currentTarget.blur()
       }}
     />
   )

src/renderer/src/settings/store.ts

@@ -24,6 +24,52 @@ let unsubscribeStoreListener: (() => void) | null = null
 /** re-entrancy guard so concurrent hydrate() calls don't double-subscribe */
 let hydrating = false
 
+/** Sub-keys of `prev` → `next` that actually changed, or undefined when none did. */
+function diffGroup<T extends object>(prev: T, next: T): Partial<T> | undefined {
+  const patch: Partial<T> = {}
+  for (const key of Object.keys(next) as (keyof T)[]) {
+    if (prev[key] !== next[key]) patch[key] = next[key]
+  }
+  return Object.keys(patch).length > 0 ? patch : undefined
+}
+
+/**
+ * Optimistic write + persist. The SETTINGS_CHANGED echo re-sets the same value
+ * (idempotent), so no rollback is needed for it. On failure, revert only while
+ * the store still holds exactly what this call wrote: a newer call (e.g. a
+ * ColorPicker drag) may already have saved a different value, and reverting
+ * would drop it from the UI although it is on disk.
+ */
+async function persist(
+  get: () => SettingsState,
+  set: (partial: Partial<SettingsState>) => void,
+  written: AppSettings,
+  prev: AppSettings,
+  label: string
+): Promise<void> {
+  set({ settings: written })
+  try {
+    // Send a minimal patch, not the full snapshot: main lets stale-but-sent
+    // fields win, so a snapshot captured before a main-process mutateSettings
+    // write (e.g. the tray's persistCloseAction) would silently revert it.
+    // Absent fields are left untouched on disk.
+    const patch: Partial<AppSettings> = {}
+    if (written.customThemes !== prev.customThemes) patch.customThemes = written.customThemes
+    if (written.highlightRules !== prev.highlightRules) patch.highlightRules = written.highlightRules
+    const terminal = diffGroup(prev.terminal, written.terminal)
+    // Main merges each group one level deep, so a group holding only the
+    // changed sub-keys is a valid patch payload even though the contract types
+    // groups as full objects.
+    if (terminal) patch.terminal = terminal as TerminalSettings
+    const system = diffGroup(prev.system, written.system)
+    if (system) patch.system = system as SystemSettings
+    await window.api.saveSettings(patch)
+  } catch (err) {
+    console.error(`[settings] ${label} failed, rolling back`, err)
+    if (get().settings === written) set({ settings: prev })
+  }
+}
+
 export const useSettingsStore = create<SettingsState>((set, get) => ({
   hydrated: false,
   settings: DEFAULT_SETTINGS,
@@ -55,52 +101,25 @@ export const useSettingsStore = create<SettingsState>((set, get) => ({
       ...prev,
       terminal: { ...prev.terminal, ...partial }
     }
-    // optimistic update; the SETTINGS_CHANGED echo will re-set the same value (idempotent)
-    set({ settings: next })
-    try {
-      await window.api.saveSettings(next)
-    } catch (err) {
-      console.error('[settings] updateTerminal failed, rolling back', err)
-      set({ settings: prev })
-    }
+    await persist(get, set, next, prev, 'updateTerminal')
   },
 
   setCustomThemes: async (themes) => {
     const prev = get().settings
     const next: AppSettings = { ...prev, customThemes: themes }
-    set({ settings: next })
-    try {
-      await window.api.saveSettings(next)
-    } catch (err) {
-      console.error('[settings] setCustomThemes failed, rolling back', err)
-      set({ settings: prev })
-    }
+    await persist(get, set, next, prev, 'setCustomThemes')
   },
 
   setHighlightRules: async (rules) => {
     const prev = get().settings
     const next: AppSettings = { ...prev, highlightRules: rules }
-    // optimistic update; the SETTINGS_CHANGED echo will re-set the same value (idempotent)
-    set({ settings: next })
-    try {
-      await window.api.saveSettings(next)
-    } catch (err) {
-      console.error('[settings] setHighlightRules failed, rolling back', err)
-      set({ settings: prev })
-    }
+    await persist(get, set, next, prev, 'setHighlightRules')
   },
 
   updateSystem: async (partial) => {
     const prev = get().settings
     const next: AppSettings = { ...prev, system: { ...prev.system, ...partial } }
-    // optimistic update; the SETTINGS_CHANGED echo will re-set the same value (idempotent)
-    set({ settings: next })
-    try {
-      await window.api.saveSettings(next)
-    } catch (err) {
-      console.error('[settings] updateSystem failed, rolling back', err)
-      set({ settings: prev })
-    }
+    await persist(get, set, next, prev, 'updateSystem')
   }
 }))
 

src/renderer/src/sftp/FilePanel.tsx

@@ -25,12 +25,32 @@ export interface FilePanelProps {
   sessionId: string
 }
 
-/** 9 permission bits: [owner r,w,x, group r,w,x, other r,w,x]. */
+/**
+ * Permission bits: [owner r,w,x, group r,w,x, other r,w,x, setuid, setgid, sticky].
+ * The last three (indices 9..11) only exist as the 4th octal digit — the grid
+ * does not toggle them, the octal input does.
+ */
 type PermBits = boolean[]
 
+const MODE_LETTERS = ['r', 'w', 'x', 'r', 'w', 'x', 'r', 'w', 'x']
+/** x-column index → index of the special bit that changes its letter. */
+const SPECIAL_BIT_AT: Record<number, number> = { 2: 9, 5: 10, 8: 11 }
+
+const emptyBits = (): PermBits => Array.from({ length: 12 }, () => false)
+
 function parseModeBits(mode: string | undefined): PermBits {
   const chars = mode ? Array.from(mode.slice(1)) : []
-  return Array.from({ length: 9 }, (_, i) => chars[i] != null && chars[i] !== '-')
+  const bits = emptyBits()
+  for (let i = 0; i < 9; i++) {
+    const c = chars[i]
+    if (c == null || c === '-') continue
+    // uppercase S/T means "special bit set, execute bit clear"
+    bits[i] = c !== 'S' && c !== 'T'
+  }
+  if (chars[2] === 's' || chars[2] === 'S') bits[9] = true
+  if (chars[5] === 's' || chars[5] === 'S') bits[10] = true
+  if (chars[8] === 't' || chars[8] === 'T') bits[11] = true
+  return bits
 }
 
 function formatModeType(mode: string | undefined): string {
@@ -39,9 +59,13 @@ function formatModeType(mode: string | undefined): string {
 }
 
 function bitsToModeStr(type: string, bits: PermBits): string {
-  const letters = bits.map((on, i) => {
-    if (!on) return '-'
-    return ['r', 'w', 'x', 'r', 'w', 'x', 'r', 'w', 'x'][i]
+  const letters = MODE_LETTERS.map((on, i) => {
+    const special = SPECIAL_BIT_AT[i]
+    if (special !== undefined && bits[special]) {
+      // setuid/setgid → s/S, sticky → t/T
+      return bits[i] ? (i === 8 ? 't' : 's') : i === 8 ? 'T' : 'S'
+    }
+    return bits[i] ? on : '-'
   })
   return type + letters.join('')
 }
@@ -56,7 +80,17 @@ function bitsToOctal(bits: PermBits): string {
   // arithmetic version computed 5*64+1*8+1 = 329 decimal, which is NOT the
   // octal "511" and made chmod a silent no-op when both sides agreed on the
   // same wrong value.)
-  return `${octalDigit(0, bits)}${octalDigit(3, bits)}${octalDigit(6, bits)}`
+  const special = (bits[9] ? 4 : 0) + (bits[10] ? 2 : 0) + (bits[11] ? 1 : 0)
+  const perms = `${octalDigit(0, bits)}${octalDigit(3, bits)}${octalDigit(6, bits)}`
+  // Keep the 3-digit form when no special bit is set so it round-trips with
+  // what main sends (its mode string is 9 bits wide).
+  return special > 0 ? `${special}${perms}` : perms
+}
+
+/** t() falls back to the key itself when a translation is missing. */
+function tOr(key: string, fallback: string): string {
+  const value = t(key)
+  return value === key ? fallback : value
 }
 
 function fmtSize(bytes: number): string {
@@ -90,12 +124,14 @@ interface PermissionModalProps {
 
 function PermissionModal({ open, sessionId, entry, onClose, onSaved }: PermissionModalProps): React.JSX.Element {
   const { message } = App.useApp()
-  const [bits, setBits] = useState<PermBits>(Array.from({ length: 9 }, () => false))
+  const [bits, setBits] = useState<PermBits>(emptyBits)
   const [octal, setOctal] = useState('')
   const [uid, setUid] = useState('')
   const [gid, setGid] = useState('')
   const [saving, setSaving] = useState(false)
   const hasUidGid = entry != null && (entry.uid != null || entry.gid != null)
+  /** lstat failed while listing → no mode to compare against or preserve. */
+  const modeKnown = Boolean(entry?.mode)
   const rowLabels = permRowLabels()
   const colLabels = permColLabels()
 
@@ -110,11 +146,11 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
     if (entry) {
       const b = parseModeBits(entry.mode)
       setBits(b)
-      setOctal(bitsToOctal(b))
+      setOctal(entry.mode ? bitsToOctal(b) : '')
       setUid(entry.uid != null ? String(entry.uid) : '')
       setGid(entry.gid != null ? String(entry.gid) : '')
     } else {
-      setBits(Array.from({ length: 9 }, () => false))
+      setBits(emptyBits())
       setOctal('')
       setUid('')
       setGid('')
@@ -125,6 +161,7 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
     const s = (v ?? '').trim()
     if (/^[0-7]{1,4}$/.test(s)) {
       const num = parseInt(s, 8) || 0
+      const special = s.length === 4 ? parseInt(s[0], 8) : 0
       setBits([
         (num >> 6) & 4 ? true : false,
         (num >> 6) & 2 ? true : false,
@@ -134,7 +171,10 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
         (num >> 3) & 1 ? true : false,
         num & 4 ? true : false,
         num & 2 ? true : false,
-        num & 1 ? true : false
+        num & 1 ? true : false,
+        (special & 4) !== 0,
+        (special & 2) !== 0,
+        (special & 1) !== 0
       ])
     }
     setOctal(s)
@@ -149,6 +189,15 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
     })
   }
 
+  /** Non-negative integer input, '' meaning "keep current". */
+  const parseId = (v: string): number | null => {
+    const s = v.trim()
+    if (s === '') return null
+    const n = Number(s)
+    return Number.isInteger(n) && n >= 0 ? n : null
+  }
+  const idInvalid = (v: string): boolean => v.trim() !== '' && parseId(v) === null
+
   const onSave = (): void => {
     void (async () => {
       if (!entry) return
@@ -156,23 +205,27 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
       try {
         const octalStr = bitsToOctal(bits)
         const curOctal = entry.mode ? bitsToOctal(parseModeBits(entry.mode)) : null
+        // Unknown mode (lstat failed): bits start all-false, so only chmod when
+        // the user actually touched something — otherwise an untouched dialog
+        // would send "chmod 000".
+        const modeChanged = curOctal === null ? bits.some(Boolean) : octalStr !== curOctal
         // Only chown when the uid/gid actually differ from the entry's current
         // owner — the inputs are seeded with the current values, so "untouched"
         // would otherwise chown on every save.
-        const newUid = uid.trim() !== '' && !Number.isNaN(Number(uid)) ? Number(uid) : null
-        const newGid = gid.trim() !== '' && !Number.isNaN(Number(gid)) ? Number(gid) : null
+        const newUid = parseId(uid)
+        const newGid = parseId(gid)
         const ownerChanged =
           (newUid !== null && newUid !== entry.uid) || (newGid !== null && newGid !== entry.gid)
 
-        if (octalStr !== curOctal) {
+        if (modeChanged) {
           await window.api.chmodRemote(sessionId, entry.path, octalStr)
         }
         if (ownerChanged) {
           const u = newUid ?? entry.uid ?? 0
-          const g = newGid ?? newUid ?? entry.gid ?? 0
+          const g = newGid ?? entry.gid ?? 0
           await window.api.chownRemote(sessionId, entry.path, u, g)
         }
-        if (octalStr !== curOctal || ownerChanged) {
+        if (modeChanged || ownerChanged) {
           message.success(t('ssh.file.permApplied'))
         }
         onClose()
@@ -194,6 +247,7 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
       confirmLoading={saving}
       okText={t('common.save')}
       cancelText={t('common.cancel')}
+      okButtonProps={{ disabled: idInvalid(uid) || idInvalid(gid) }}
       width={380}
     >
       <div className="sftp-perm">
@@ -253,6 +307,10 @@ function PermissionModal({ open, sessionId, entry, onClose, onSaved }: Permissio
           </div>
         </div>
         <div className="sftp-perm-hint">{t('ssh.file.ownerHint')}</div>
+        {entry && !modeKnown && <div className="sftp-perm-hint">{t('ssh.file.modeUnavailable')}</div>}
+        {(idInvalid(uid) || idInvalid(gid)) && (
+          <div className="sftp-perm-hint">{t('main.sftp.invalidUidGid')}</div>
+        )}
       </div>
     </Modal>
   )
@@ -302,18 +360,74 @@ export function FilePanel({ sessionId }: FilePanelProps): React.JSX.Element {
 
   const selectedPath = selected?.path ?? ''
 
+  /** local file name as main computes it for the remote path (basename). */
+  const remoteNameOf = (local: string): string => local.split(/[\\/]/).pop() ?? local
+
+  /**
+   * Start the upload. The listener is registered BEFORE the transfer id is
+   * known: uploadRemote resolves with the id right away while the transfer
+   * itself runs detached, so a small file can finish before the id arrives —
+   * registering afterwards would miss the terminal event and never refresh.
+   */
+  const startUpload = (files: string[]): void => {
+    let targetId: string | null = null
+    let settled = false
+    const earlyTerminalIds: string[] = []
+    const finish = (): void => {
+      if (settled) return
+      settled = true
+      off()
+      void refresh(dir)
+    }
+    const off = window.api.onTransferProgress((e: TransferProgressEvent) => {
+      if (e.state !== 'done' && e.state !== 'error' && e.state !== 'cancelled') return
+      if (targetId === null) {
+        earlyTerminalIds.push(e.transferId)
+        return
+      }
+      if (e.transferId === targetId) finish()
+    })
+    window.api.uploadRemote(sessionId, files, dir).then(
+      (id: string) => {
+        targetId = id
+        if (earlyTerminalIds.includes(id)) finish()
+      },
+      (err: unknown) => {
+        off()
+        message.error((err as Error).message)
+      }
+    )
+  }
+
   const doUpload = (): void => {
     void (async () => {
       try {
-        const files = await window.api.pickFiles()
+        // Explicit type: env.d.ts resolves `AppApi` through a wrong path, so
+        // `window.api` is untyped and the callback params lose their context.
+        const files: string[] = await window.api.pickFiles()
         if (files.length === 0) return
-        await window.api.uploadRemote(sessionId, files, dir)
-        // refresh when the transfer completes
-        const off = window.api.onTransferProgress((e: TransferProgressEvent) => {
-          if (e.state === 'done' || e.state === 'error' || e.state === 'cancelled') {
-            off()
-            void refresh(dir)
-          }
+        // Main opens the target with 'w' (truncate), so an existing file would
+        // be silently overwritten — ask first, like delete and clear-history do.
+        const existing = files.map(remoteNameOf).filter((name) => entries.some((e) => e.name === name))
+        if (existing.length === 0) {
+          startUpload(files)
+          return
+        }
+        const desc = tOr('ssh.file.overwriteDesc', '')
+        modal.confirm({
+          title: tOr('ssh.file.overwriteTitle', t('ssh.file.uploadFile')),
+          content: (
+            <div>
+              {existing.map((name) => (
+                <div key={name}>{name}</div>
+              ))}
+              {desc && <div>{desc}</div>}
+            </div>
+          ),
+          okText: t('common.ok'),
+          okButtonProps: { danger: true },
+          cancelText: t('common.cancel'),
+          onOk: () => startUpload(files)
         })
       } catch (err) {
         message.error((err as Error).message)

src/renderer/src/sftp/TransferPanel.tsx

@@ -1,14 +1,16 @@
-import { useEffect, useRef, useState } from 'react'
+import { useCallback, useEffect, useRef, useState } from 'react'
 import { CloseOutlined } from '@ant-design/icons'
-import type { TransferKind, TransferProgressEvent } from '@shared/sftp'
+import type { TransferKind, TransferProgressEvent, TransferState } from '@shared/sftp'
 import { t } from '@shared/i18n'
 
-interface TransferState {
+/** One aggregated transfer row in the overlay (the per-event state string is
+ *  the shared `TransferState`). */
+interface TransferEntry {
   kind: TransferKind
   file: string
   bytes: number
   totalBytes: number
-  state: 'running' | 'done' | 'error' | 'cancelled'
+  state: TransferState
   error?: string
 }
 
@@ -17,13 +19,29 @@ interface TransferState {
  * transferId; done transfers fade out, errors stay until dismissed.
  */
 export function TransferPanel(): React.JSX.Element | null {
-  const [transfers, setTransfers] = useState<Map<string, TransferState>>(new Map())
-  const timersRef = useRef<number[]>([])
+  const [transfers, setTransfers] = useState<Map<string, TransferEntry>>(new Map())
+  /** auto-dismiss timers, keyed by transfer id (never more than one per run) */
+  const timersRef = useRef<Map<string, number>>(new Map())
+
+  const dismiss = useCallback((id: string): void => {
+    const timer = timersRef.current.get(id)
+    if (timer !== undefined) {
+      window.clearTimeout(timer)
+      timersRef.current.delete(id)
+    }
+    setTransfers((prev) => {
+      if (!prev.has(id)) return prev
+      const next = new Map(prev)
+      next.delete(id)
+      return next
+    })
+  }, [])
 
   useEffect(() => {
     const off = window.api.onTransferProgress((e: TransferProgressEvent) => {
       setTransfers((prev) => {
         const next = new Map(prev)
+        const existing = next.get(e.transferId)
         if (e.file) {
           next.set(e.transferId, {
             kind: e.kind,
@@ -34,42 +52,51 @@ export function TransferPanel(): React.JSX.Element | null {
             error: e.error
           })
         } else {
-          // terminal event for the whole transfer
-          const existing = next.get(e.transferId)
-          if (existing) {
-            if (e.state === 'error') {
-              next.set(e.transferId, { ...existing, state: 'error', error: e.error })
-            } else if (e.state === 'cancelled') {
-              next.set(e.transferId, { ...existing, state: 'cancelled' })
-            } else {
-              next.set(e.transferId, { ...existing, state: 'done' })
-            }
+          // Terminal event for the whole transfer. It can arrive without any
+          // per-file progress first (e.g. the remote open was denied), so a
+          // missing entry is created rather than dropped — otherwise the
+          // failure would be visible nowhere.
+          const base: TransferEntry = existing ?? {
+            kind: e.kind,
+            file: '',
+            bytes: e.bytes,
+            totalBytes: e.totalBytes,
+            state: 'running'
+          }
+          if (e.state === 'error') {
+            next.set(e.transferId, { ...base, state: 'error', error: e.error })
+          } else if (e.state === 'cancelled') {
+            next.set(e.transferId, { ...base, state: 'cancelled' })
+          } else {
+            next.set(e.transferId, { ...base, state: 'done' })
           }
         }
         return next
       })
     })
-    return () => {
-      off()
-      for (const t of timersRef.current) window.clearTimeout(t)
-    }
+    return off
   }, [])
 
   // auto-dismiss finished entries after 3s
   useEffect(() => {
-    for (const [id, t] of transfers) {
-      if ((t.state === 'done' || t.state === 'cancelled') && !t.error) {
+    for (const [id, tr] of transfers) {
+      if ((tr.state === 'done' || tr.state === 'cancelled') && !tr.error && !timersRef.current.has(id)) {
         const timer = window.setTimeout(() => {
-          setTransfers((prev) => {
-            const next = new Map(prev)
-            next.delete(id)
-            return next
-          })
+          timersRef.current.delete(id)
+          dismiss(id)
         }, 3000)
-        timersRef.current.push(timer)
+        timersRef.current.set(id, timer)
       }
     }
-  }, [transfers])
+  }, [transfers, dismiss])
+
+  useEffect(() => {
+    const timers = timersRef.current
+    return () => {
+      for (const timer of timers.values()) window.clearTimeout(timer)
+      timers.clear()
+    }
+  }, [])
 
   const list = [...transfers.entries()]
   if (list.length === 0) return null
@@ -100,13 +127,7 @@ export function TransferPanel(): React.JSX.Element | null {
                 <button
                   type="button"
                   className="sftp-transfer-close"
-                  onClick={() =>
-                    setTransfers((prev) => {
-                      const next = new Map(prev)
-                      next.delete(id)
-                      return next
-                    })
-                  }
+                  onClick={() => dismiss(id)}
                 >
                   <CloseOutlined />
                 </button>

src/renderer/src/terminal/TerminalView.tsx

@@ -14,7 +14,7 @@ import type { CommandItem } from '@shared/commands'
 import type { TerminalSettings } from '@shared/settings'
 import { useSettingsStore } from '@renderer/settings/store'
 import { writeBroadcast } from '@renderer/workspace/broadcastStore'
-import { compileRules, HighlightStream, type CompiledRule } from './highlightEngine'
+import { compileRules, HighlightStream } from './highlightEngine'
 import { findUrls } from './urlLinks'
 import { subscribePtyData, subscribePtyExit } from './ptyDispatcher'
 import { cdArgument, conemuCwd } from './cwdTracker'
@@ -139,39 +139,17 @@ function SearchBar({ value, onChange, onPrev, onNext, onClose, enabled, result }
  * handled here; escape sequences (\x1b) and the leading non-printable control
  * bytes on a chunk — like \x1b[K clear-line — never enter the buffer.
  *
- * `rewrite` flags a completion acceptance that just rewrote the shell line (a
- * Ctrl+U kill + full-command write). The very next onData chunk is the shell's
- * redraw echoing the accepted line, so instead of appending onto the stale
- * pre-accept buffer we *replace* it with what the pty actually echoed. This is
- * the echo-suppression that keeps the local buffer in sync with the shell and
- * prevents the accepted text from being duplicated.
+ * readline's line-editing keys (Ctrl+U/W/K, Ctrl+A/E/L/Y, …) are handled too:
+ * the shell applies them to its own line and never echoes the resulting edit
+ * back to us, so appending the raw control byte would silently desync this
+ * buffer from the shell's line and make the history record the pre-edit text.
  */
 function stepLineBuffer(
   outBuf: React.MutableRefObject<string>,
-  data: string,
-  rewrite: boolean
+  data: string
 ): { line: string; submit?: string } {
   const b = outBuf.current
   if (!data) return { line: b }
-  // Completion-rewrite redraw: reset to this chunk's visible text verbatim. For
-  // a shell like PowerShell the redraw is a leading escape/control sequence
-  // + the line text; strip leading control bytes so only the echoed command
-  // enters the buffer (matching how a normal chunk is captured). Any trailing
-  // text on the chunk is appended as usual.
-  if (rewrite) {
-    let i = 0
-    while ((data[i] === '\x1b' && (data[i + 1] === '[' || data[i + 1] === '(')) || data[i] === '\r' || data[i] === '\n') {
-      i += data[i] === '\x1b' ? 2 : 1
-    }
-    const visible = data.slice(i)
-    if (visible) {
-      outBuf.current = visible
-      return { line: visible }
-    }
-    // Only control output (e.g. the kill sequence handling) — treat as a reset.
-    outBuf.current = ''
-    return { line: '' }
-  }
   // xterm-native paste (plain Ctrl+V): with the shell's bracketed-paste mode
   // on, the pasted block arrives wrapped in \x1b[200~ / \x1b[201~ and the chunk
   // starts with ESC, which the guards below would drop wholesale. Strip the
@@ -195,6 +173,21 @@ function stepLineBuffer(
     return { line: '' }
   }
   if (first === '\x1b') return { line: b }
+  // Ctrl+U / Ctrl+K kill the shell's line (before / after the cursor); with no
+  // cursor tracking the safe mirror of that is an empty buffer.
+  if (first === '\x15' || first === '\x0b') {
+    outBuf.current = ''
+    return { line: '' }
+  }
+  // Ctrl+W: readline skips trailing whitespace and kills the word before it.
+  if (first === '\x17') {
+    outBuf.current = b.replace(/\S+\s*$/, '')
+    return { line: outBuf.current }
+  }
+  // Any other C0 byte is a key the shell interprets itself (Ctrl+A/E/L/Y,
+  // Ctrl+R, Ctrl+D, Tab, …) and adds no text to the line — the buffer must not
+  // grow either.
+  if (data.charCodeAt(0) < 0x20) return { line: b }
   outBuf.current = b + data
   return { line: outBuf.current }
 }
@@ -273,17 +266,12 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
   const searchTermRef = useRef('')
   const nativePasteRef = useRef<string | null>(null)
   const onCloseRef = useRef(onClose)
-  const compiledRef = useRef<CompiledRule[]>([])
   const streamRef = useRef<HighlightStream | null>(null)
+  // Renderer mode currently installed on the terminal, so the mode effect can
+  // tell a real switch from its own mount-time run.
+  const rendererModeRef = useRef<TerminalSettings['rendererMode'] | null>(null)
   // M5: per-session line-capture buffer + completion candidate cache.
   const lineBufRef = useRef<string>('')
-  // M5: when a completion acceptance rewrites the shell line (Ctrl+U + full
-  // command via writeBroadcast in `differenceWrite`), the shell answers with a
-  // redraw that echoes `full`. If that echo were folded into the local buffer
-  // on top of the pre-accept text it would double the line. `diffRewriteRef`
-  // flags that the *next* onData chunk is that redraw output, so stepLineBuffer
-  // replaces the buffer with the freshly-echoed line instead of appending.
-  const diffRewriteRef = useRef(false)
   const completionCacheRef = useRef<CommandItem[]>([])
   const completionKeyRef = useRef('')
   const recordingRef = useRef(false)
@@ -302,7 +290,6 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
   // latest rules without triggering a terminal rebuild. Only new output is
   // highlighted — the existing scrollback buffer is left untouched.
   const compiledRules = useMemo(() => compileRules(settings.highlightRules), [settings.highlightRules])
-  compiledRef.current = compiledRules
   streamRef.current?.setRules(compiledRules)
 
   // M5: load completion candidates once per session (history + library cached).
@@ -352,7 +339,10 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
       webglRef.current.dispose()
       webglRef.current = null
     }
-    if (mode === 'dom') return
+    if (mode === 'dom') {
+      rendererModeRef.current = mode
+      return
+    }
     try {
       const webgl = new WebglAddon()
       webgl.onContextLoss(() => {
@@ -366,6 +356,7 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
     } catch {
       webglRef.current = null
     }
+    rendererModeRef.current = mode
   }, [])
 
   const scheduleFit = useCallback(() => {
@@ -386,6 +377,13 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
       const send = (): void => {
         const live = termRef.current
         if (!live || deadRef.current) return
+        // A pane without a layout box (hidden or not-yet-laid-out dock tab)
+        // reports a degenerate grid; that — and any other sub-minimum size —
+        // must never reach the pty, which would reflow the shell into a
+        // one-column line. Skipping leaves ptySizeRef untouched, so the next
+        // fit retries instead of remembering the bad size.
+        if (hostRef.current?.offsetParent === null) return
+        if (live.cols < 20 || live.rows < 4) return
         if (live.cols === ptySizeRef.current?.cols && live.rows === ptySizeRef.current?.rows) return
         ptySizeRef.current = { cols: live.cols, rows: live.rows }
         window.api.resizePty(sessionId, live.cols, live.rows)
@@ -555,8 +553,11 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
     } catch {
       /* clipboard write denied */
     }
-    if (!settings.terminal.copyOnSelect) term.clearSelection()
-  }, [settings.terminal.copyOnSelect])
+    // Read the setting at call time: this runs from the terminal's custom key
+    // handler, which is attached once per session and would otherwise keep the
+    // copyOnSelect value captured at mount.
+    if (!useSettingsStore.getState().settings.terminal.copyOnSelect) term.clearSelection()
+  }, [])
 
   const pasteFromClipboard = useCallback(async () => {
     try {
@@ -573,11 +574,11 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
     (selected: CommandItem): void => {
       const cmd = selected.command
       // Rewrite the whole shell line (Ctrl+U then `cmd`) instead of appending a
-      // delta — the pty redraw, not our local buffer, becomes the source of
-      // truth for the line (see differenceWrite). The redraw trigger sets the
-      // rewrite flag so onData resets the line buffer to the echoed line.
+      // delta, so the pty never has to reconcile our local buffer with its own
+      // (see differenceWrite). The local buffer mirrors the rewrite — the shell
+      // does not echo it back through onData, so nothing else would update it,
+      // and the next Enter would otherwise record the pre-accept text.
       differenceWrite(sessionId, cmd, lineBufRef.current)
-      diffRewriteRef.current = true
       lineBufRef.current = cmd
       suggestionsRef.current = []
       selIndexRef.current = 0
@@ -792,15 +793,27 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
           rows.push({ index: row, text: line.translateToString(false) })
         }
         const text = rows.map((r) => r.text).join('')
+        // translateToString emits one char per cell run — a double-width char
+        // is ONE char spanning TWO columns — so a char offset cannot be mapped
+        // to a column with `% cols` (every CJK char on the line shifts the
+        // link range). Walk the cells once and record the 1-based x / buffer
+        // row of each char position in `text`.
         const cols = term.cols > 0 ? term.cols : 1
-        const base = rows[0]?.index ?? first
+        const colAt: number[] = []
+        const rowAt: number[] = []
+        for (const { index: row } of rows) {
+          const line = buffer.getLine(row)
+          for (let col = 0; col < cols; col++) {
+            if ((line?.getCell(col)?.getWidth() ?? 1) === 0) continue // wide-char tail
+            colAt.push(col + 1)
+            rowAt.push(row)
+          }
+        }
         const links: ILink[] = findUrls(text).map((found) => {
-          const startRow = Math.floor(found.start / cols)
-          const endRow = Math.floor((found.end - 1) / cols)
           return {
             range: {
-              start: { x: (found.start % cols) + 1, y: base + startRow + 1 },
-              end: { x: ((found.end - 1) % cols) + 1, y: base + endRow + 1 }
+              start: { x: colAt[found.start] ?? 1, y: (rowAt[found.start] ?? first) + 1 },
+              end: { x: colAt[found.end - 1] ?? 1, y: (rowAt[found.end - 1] ?? first) + 1 }
             },
             text: found.url,
             decorations: { pointerCursor: true, underline: true },
@@ -822,10 +835,6 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
       linkProvider,
       term.onData((data) => {
         if (!deadRef.current) writeBroadcast(sessionId, data)
-        // M5: a completion acceptance rewrite armed `diffRewriteRef`; consume it
-        // now so this redraw chunk replaces (not appends to) the line buffer.
-        const consumeRewrite = diffRewriteRef.current
-        diffRewriteRef.current = false
         // Full-screen TUIs (vim, Claude Code, …) own the alternate buffer, their
         // own key handling and their own cursor: the line buffer, the command
         // history and the completion popup have no business there. Interfering
@@ -841,8 +850,10 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
           }
           return
         }
-        // M5: line capture → recordCommand + inline completion overlay.
-        const step = stepLineBuffer(lineBufRef, data, consumeRewrite)
+        // M5: line capture → recordCommand + inline completion overlay. Only user
+        // input reaches onData; the shell's own redraws arrive on the pty path,
+        // which never touches the buffer.
+        const step = stepLineBuffer(lineBufRef, data)
         if (typeof step.submit === 'string' && step.submit) {
           trackSubmittedLine(step.submit)
         }
@@ -1005,6 +1016,9 @@ export const TerminalView: ForwardRefExoticComponent<TerminalViewProps & { ref?:
   // ---- renderer mode changes: keep the instance, swap renderer, refit ----
   useEffect(() => {
     const next = tSettings.rendererMode
+    // The construction effect above already applied the mode on mount (this
+    // effect runs on mount too); only an actual switch should re-run it.
+    if (next === rendererModeRef.current) return
     if (next === 'dom') {
       applyRenderers('dom')
     } else if (!webglRef.current) {

src/renderer/src/terminal/highlightEngine.ts

@@ -33,6 +33,16 @@ const ESCAPE_RE =
 const MAX_PER_RULE = 300
 /** Chunks larger than this are returned unmodified (budget guard). */
 const MAX_CHUNK = 512 * 1024
+/**
+ * Longest newline-free segment of a plain-text run a user rule is applied to.
+ * MAX_PER_RULE bounds the match *count*, not a pattern's backtracking *cost*:
+ * a pathological pattern like `(a+)+b` walks the whole line before the count
+ * can stop it, which freezes the renderer on one very long line. A run holding
+ * such a line is passed through unhighlighted — ordinary output (many short
+ * lines, whatever the chunk size) is unaffected, since the bound is per line,
+ * not per run.
+ */
+const MAX_LINE_LEN = 4 * 1024
 
 /** "#rrggbb" or 3-digit "#rgb" → {r,g,b}; any malformed input → white. */
 export function hexToRgb(hex: string): { r: number; g: number; b: number } {
@@ -107,14 +117,26 @@ function overlaps(claimed: Span[], s: number, e: number): boolean {
   return false
 }
 
+/** True when `text` holds a newline-free segment longer than MAX_LINE_LEN. */
+function hasLongLine(text: string): boolean {
+  let start = 0
+  for (;;) {
+    const nl = text.indexOf('\n', start)
+    if (nl < 0) return text.length - start > MAX_LINE_LEN
+    if (nl - start > MAX_LINE_LEN) return true
+    start = nl + 1
+  }
+}
+
 /**
  * Apply all rules to a single plain-text run. Consumes from `budgets` (per-rule
  * remaining match allowance shared across the whole chunk). Returns the
  * SGR-injected text. With a global budget of zero for every rule the run is
- * returned untouched.
+ * returned untouched, as is a run holding an over-long line (see MAX_LINE_LEN).
  */
 function applyRun(text: string, rules: CompiledRule[], budgets: number[]): string {
   if (text.length === 0) return ''
+  if (hasLongLine(text)) return text
   const claimed: Span[] = []
   for (let ri = 0; ri < rules.length; ri++) {
     const rule = rules[ri]

src/renderer/src/theme/chrome.ts

@@ -22,6 +22,14 @@ function toHex(v: number): string {
   return Math.max(0, Math.min(255, Math.round(v))).toString(16).padStart(2, '0')
 }
 
+/** WCAG contrast ratio between two colors; 21 when either is not hex. */
+function contrast(a: string, b: string): number {
+  const la = luminance(a)
+  const lb = luminance(b)
+  if (la === null || lb === null) return 21
+  return (Math.max(la, lb) + 0.05) / (Math.min(la, lb) + 0.05)
+}
+
 /** t=0 → a, t=1 → b */
 export function mix(a: string, b: string, t: number): string | null {
   const ca = parseHex(a)
@@ -34,6 +42,18 @@ export function mix(a: string, b: string, t: number): string | null {
  *  from it flip their overlay direction (white-on-dark vs black-on-light). */
 let chromeIsLight = false
 
+/** Dark-chrome tab label: the background mixed toward the theme's own foreground
+ *  (the light branch is the same mix toward black), but never below 4.5:1 against
+ *  the background, since a theme foreground dimmed by 0.68 can land unreadable. */
+function tabLabel(background: string, foreground: string, t: number): string {
+  const mixed = mix(background, foreground, t)
+  return mixed && contrast(mixed, background) >= 4.5 ? mixed : foreground
+}
+
+/** Accent color from the last applyTabAccent() call; re-applied at the end of a
+ *  chrome theme change so --tab-accent-fg follows the new theme's luminance. */
+let tabAccent = ''
+
 /** Derive the app chrome palette (sidebar, tab bars, dividers) from the active
  *  terminal theme so the whole window follows theme switches instead of only
  *  the terminal canvas. Values land on :root CSS variables; anything the theme
@@ -67,9 +87,10 @@ export function applyChromeTheme(colors: ThemeColors): void {
     set('--chrome-tab-bg-hover', 'rgba(255, 255, 255, 0.07)')
     set('--chrome-tab-ring', 'rgba(255, 255, 255, 0.1)')
     set('--chrome-tab-ring-hover', 'rgba(255, 255, 255, 0.2)')
-    set('--chrome-tab-fg', '#98a2ab')
-    set('--chrome-tab-fg-hover', '#d0d0d0')
+    set('--chrome-tab-fg', tabLabel(colors.background, colors.foreground, 0.68))
+    set('--chrome-tab-fg-hover', tabLabel(colors.background, colors.foreground, 0.88))
   }
+  applyTabAccent(tabAccent)
 }
 
 /** Tab accent: base color + a foreground variant that stays readable on the
@@ -77,6 +98,7 @@ export function applyChromeTheme(colors: ThemeColors): void {
  *  var(--tab-accent*) in workspace.css. */
 export function applyTabAccent(color: string): void {
   const style = document.documentElement.style
+  tabAccent = color
   // Settings hydrated from an older main process may lack the key; clear the
   // vars so the CSS fallbacks apply instead of an invalid "undefined" value.
   if (!color) {

src/renderer/src/workspace/SshBottomPanel.tsx

@@ -15,49 +15,79 @@ const MIN_HEIGHT = 120
 export function SshBottomPanel({ sessionId, terminal }: SshBottomPanelProps): React.JSX.Element {
   /** Current file-browser height in px. */
   const [filesHeight, setFilesHeight] = useState<number>(220)
-  /** Container height captured while a drag is in flight. */
-  const dragInfoRef = useRef<{ startY: number; startHeight: number; containerH: number } | null>(null)
+  /** Divider drag in flight — drives the accent highlight. */
+  const [resizing, setResizing] = useState(false)
+  const rootRef = useRef<HTMLDivElement>(null)
+  /** Drag origin; non-null only while a divider drag is in flight. */
+  const dragRef = useRef<{ startY: number; startHeight: number } | null>(null)
+  /** Live container height, refreshed by the observer below: clamping against a
+   *  height captured at mousedown keeps a stale maximum after a window resize. */
+  const containerHRef = useRef(0)
 
-  const onDividerMouseDown = useCallback((e: React.MouseEvent<HTMLDivElement>): void => {
-    if (e.button !== 0) return
-    const container = (e.currentTarget.parentElement as HTMLElement | null) ?? null
-    if (!container) return
-    dragInfoRef.current = {
-      startY: e.clientY,
-      startHeight: filesHeight,
-      containerH: container.clientHeight
-    }
-    e.preventDefault()
-  }, [filesHeight])
+  const clampHeight = useCallback((height: number): number => {
+    return Math.max(MIN_HEIGHT, Math.min(Math.round(containerHRef.current * 0.6), height))
+  }, [])
 
+  // Re-clamp on container resize: a shrunk window would otherwise leave the file
+  // browser taller than 60% of the panel, collapsing the terminal.
   useEffect(() => {
-    const onMove = (e: MouseEvent): void => {
-      const info = dragInfoRef.current
+    const root = rootRef.current
+    if (!root) return
+    const observer = new ResizeObserver(() => {
+      containerHRef.current = root.clientHeight
+      setFilesHeight((prev) => clampHeight(prev))
+    })
+    observer.observe(root)
+    return () => observer.disconnect()
+  }, [clampHeight])
+
+  const onDividerPointerDown = useCallback(
+    (e: React.PointerEvent<HTMLDivElement>): void => {
+      if (e.button !== 0) return
+      const root = rootRef.current
+      if (!root) return
+      containerHRef.current = root.clientHeight
+      dragRef.current = { startY: e.clientY, startHeight: filesHeight }
+      // Pointer capture keeps move/up events coming even when the pointer leaves
+      // the window, so a release outside it cannot strand the drag.
+      e.currentTarget.setPointerCapture(e.pointerId)
+      setResizing(true)
+      e.preventDefault()
+    },
+    [filesHeight]
+  )
+
+  const onDividerPointerMove = useCallback(
+    (e: React.PointerEvent<HTMLDivElement>): void => {
+      const info = dragRef.current
       if (!info) return
-      const delta = e.clientY - info.startY
-      const max = Math.round(info.containerH * 0.6)
-      setFilesHeight(Math.min(max, Math.max(MIN_HEIGHT, info.startHeight - delta)))
-    }
-    const onUp = (): void => {
-      dragInfoRef.current = null
-    }
-    window.addEventListener('mousemove', onMove)
-    window.addEventListener('mouseup', onUp)
-    return () => {
-      window.removeEventListener('mousemove', onMove)
-      window.removeEventListener('mouseup', onUp)
+      setFilesHeight(clampHeight(info.startHeight - (e.clientY - info.startY)))
+    },
+    [clampHeight]
+  )
+
+  const endDrag = useCallback((e: React.PointerEvent<HTMLDivElement>): void => {
+    if (!dragRef.current) return
+    dragRef.current = null
+    setResizing(false)
+    if (e.currentTarget.hasPointerCapture(e.pointerId)) {
+      e.currentTarget.releasePointerCapture(e.pointerId)
     }
   }, [])
 
   return (
-    <div className="ssh-bottom-panel">
+    <div className="ssh-bottom-panel" ref={rootRef}>
       <div className="ssh-bottom-top">{terminal}</div>
       <div
-        className="ssh-bottom-divider"
+        className={'ssh-bottom-divider' + (resizing ? ' is-resizing' : '')}
         role="separator"
         aria-orientation="horizontal"
         aria-label={t('ssh.bottomPanel.resize')}
-        onMouseDown={onDividerMouseDown}
+        onPointerDown={onDividerPointerDown}
+        onPointerMove={onDividerPointerMove}
+        onPointerUp={endDrag}
+        onPointerCancel={endDrag}
+        onLostPointerCapture={endDrag}
       />
       <div className="ssh-bottom-files" style={{ height: filesHeight }}>
         <FilePanel sessionId={sessionId} />

src/renderer/src/workspace/TerminalPanel.tsx

@@ -42,17 +42,23 @@ export function TerminalPanel({ params, api, onSessionDead }: TerminalPanelProps
   const [sideOpen, setSideOpen] = useState(true)
 
   // M6 broadcast: keep the session in the broadcast registry while mounted so
-  // it can be picked as a target / receive fan-out writes (idempotent upsert).
+  // it can be picked as a target / receive fan-out writes. Registrations are
+  // keyed by panel id — an SSH split shows one session in two panes, and
+  // unmounting one of them must not unregister the other.
   useEffect(() => {
-    useBroadcastStore.getState().registerSession({ id: sessionId, title: api.title ?? '', isSsh })
-    return () => useBroadcastStore.getState().unregisterSession(sessionId)
+    useBroadcastStore
+      .getState()
+      .registerSession({ id: sessionId, panelId: api.id, title: api.title ?? '', isSsh })
+    return () => useBroadcastStore.getState().unregisterSession(api.id)
     // eslint-disable-next-line react-hooks/exhaustive-deps -- api is stable; title kept fresh below
   }, [sessionId])
 
   // M6: keep the registered broadcast title in sync with the tab title.
   useEffect(() => {
     const disposable = api.onDidTitleChange((event) => {
-      useBroadcastStore.getState().registerSession({ id: sessionId, title: event.title, isSsh })
+      useBroadcastStore
+        .getState()
+        .registerSession({ id: sessionId, panelId: api.id, title: event.title, isSsh })
     })
     return () => disposable.dispose()
   }, [api, sessionId, isSsh])

src/renderer/src/workspace/TerminalTab.tsx

@@ -63,12 +63,15 @@ export function TerminalTab({ api, params }: TerminalTabProps): React.JSX.Elemen
       if (key === 'close') {
         api.close()
       } else if (key === 'closeOthers') {
-        for (const sibling of panel.panels) {
+        // `panel.panels` is the live group array and `close()` splices it, so
+        // the targets must be snapshotted first — otherwise every element that
+        // shifts into the current index is skipped.
+        for (const sibling of [...panel.panels]) {
           if (sibling.api !== api) closePanel(sibling)
         }
       } else if (key === 'closeRight') {
-        for (let i = selfIndex + 1; i < panel.panels.length; i++) {
-          closePanel(panel.panels[i])
+        for (const target of [...panel.panels].slice(selfIndex + 1)) {
+          closePanel(target)
         }
       }
     }

src/renderer/src/workspace/Workspace.tsx

@@ -17,6 +17,7 @@ import type {
   DockviewApi,
   DockviewPanelApi,
   DockviewReadyEvent,
+  DockviewTheme,
   IDockviewHeaderActionsProps,
   IDockviewPanel,
   IDockviewPanelHeaderProps,
@@ -61,6 +62,54 @@ export type { TerminalParams }
 const TERMINAL_COMPONENT = 'terminal'
 const TERMINAL_TAB_COMPONENT = 'terminal-tab'
 
+/**
+ * Sessions we already asked to kill — kill once, never twice.
+ *
+ * Module-level rather than a ref so the dockview `components` /
+ * `tabComponents` maps below can be module constants: dockview re-runs its prop
+ * effects on every identity change and each `updateOptions` ends in an
+ * unconditional `_layoutFromShell()`.
+ */
+const deadSessions = new Set<string>()
+
+/** Mark a session dead ahead of a panel close so the cleanup skips it. */
+function markSessionDead(sessionId: string): void {
+  deadSessions.add(sessionId)
+}
+
+const DOCKVIEW_THEME: DockviewTheme = {
+  name: 'Abyss',
+  className: 'dockview-theme-abyss',
+  colorScheme: 'dark'
+}
+
+const DOCKVIEW_COMPONENTS = {
+  [TERMINAL_COMPONENT]: (props: IDockviewPanelProps<TerminalParams>) => (
+    <TerminalPanel {...props} onSessionDead={markSessionDead} />
+  )
+}
+
+const DOCKVIEW_TAB_COMPONENTS = {
+  [TERMINAL_TAB_COMPONENT]: (props: IDockviewPanelHeaderProps<TerminalParams>) => (
+    <TerminalTab {...props} />
+  )
+}
+
+/**
+ * Electron re-throws a main-process rejection as
+ * `Error: Error invoking remote method 'x': Error: <real message>`, so the real
+ * cause has to be unwrapped to be worth showing.
+ */
+function connectFailureMessage(error: unknown): string {
+  const generic = t('workspace.connect.failed')
+  if (!(error instanceof Error)) return generic
+  const detail = error.message
+    .replace(/^Error invoking remote method '[^']*':\s*/, '')
+    .replace(/^Error:\s*/, '')
+    .trim()
+  return detail ? `${generic}: ${detail}` : generic
+}
+
 /**
  * "终端 N" titles fill the lowest free number among live panels: closing a
  * pane frees its number for the next new terminal, and a session restore can
@@ -230,7 +279,7 @@ const SshTabActions = createTabActions('ssh')
  * (React state / panel instances stay mounted, so the switch is free).
  *
  * Sessions: panels carry a `params.sessionId`. Killing a session is idempotent
- * through `deadSessionsRef` so a session is killed at most once — either
+ * through the `deadSessions` set so a session is killed at most once — either
  * up-front (TerminalView `onClose` after the process exits) or when its panel
  * is removed. Each dockview registers `onDidRemovePanel` so a panel close in
  * either workspace kills the bound session.
@@ -255,8 +304,6 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
   /** The currently-visible mode's active panel (broadcast target). */
   const activePanelRef = useRef<IDockviewPanel | undefined>(undefined)
 
-  /** Sessions we already asked to kill — kill once, never twice. */
-  const deadSessionsRef = useRef<Set<string>>(new Set())
   /** Bind-time disposables for both dockviews, disposed on unmount. */
   const disposablesRef = useRef<Array<{ dispose(): void }>>([])
 
@@ -264,6 +311,8 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
   const [applyOpen, setApplyOpen] = useState(false)
   /** Terminal dockview ready — gates first-run seeding. */
   const [terminalReady, setTerminalReady] = useState(false)
+  /** Settings hydrate is async — the boot pass must not read its defaults. */
+  const settingsHydrated = useSettingsStore((s) => s.hydrated)
 
   /** Local terminal panels surfaced to the sidebar's "终端" section. */
   const [localPanels, setLocalPanels] = useState<Array<{ id: string; title: string }>>([])
@@ -283,8 +332,12 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
   }, [])
   /** one pending SSH connection request (null = idle). */
   const [requestedConn, setRequestedConn] = useState<SshConnection | null>(null)
-  /** true while openSession is in flight — drives the "连接中…" modal. */
-  const [connecting, setConnecting] = useState(false)
+  /** In-flight openSession attempts (0 = idle); the rail busy dot reads it. */
+  const [connectingCount, setConnectingCount] = useState(0)
+  const connecting = connectingCount > 0
+  /** Re-entrancy guard for `connect` — a second attempt while one is in flight
+   *  is dropped (openSession cannot be aborted and would orphan a session). */
+  const connectInFlightRef = useRef(0)
   /** FIFO of pending host-key confirmations — render the head only. */
   const [hostKeyQueue, setHostKeyQueue] = useState<HostKeyPromptEvent[]>([])
 
@@ -342,16 +395,11 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
   /** Idempotently kill a pty session. */
   const killSession = useCallback((sessionId: string | undefined): void => {
     if (!sessionId) return
-    if (deadSessionsRef.current.has(sessionId)) return
-    deadSessionsRef.current.add(sessionId)
+    if (deadSessions.has(sessionId)) return
+    deadSessions.add(sessionId)
     window.api.killPty(sessionId)
   }, [])
 
-  /** Mark a session dead ahead of a panel close so the cleanup skips it. */
-  const markSessionDead = useCallback((sessionId: string): void => {
-    deadSessionsRef.current.add(sessionId)
-  }, [])
-
   const createSession = useCallback(async (cwd?: string): Promise<string> => {
     // `cwd` is the memory hook: a restored pane and a freshly opened one both
     // start where the user left off. The main process validates the path and
@@ -366,14 +414,19 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
    *  terminal dockview holds only local sessions, so it is the single source. */
   const recomputeLocalPanels = useCallback((): void => {
     const current = terminalApiRef.current
-    if (!current) {
-      setLocalPanels([])
-      return
-    }
-    const panels = current.panels
-      .filter((p) => (p.params as TerminalParams | undefined)?.sessionKind === 'local')
-      .map((p) => ({ id: p.id, title: p.title ?? '' }))
-    setLocalPanels(panels)
+    const panels = current
+      ? current.panels
+          .filter((p) => (p.params as TerminalParams | undefined)?.sessionKind === 'local')
+          .map((p) => ({ id: p.id, title: p.title ?? '' }))
+      : []
+    // Keep the previous array when nothing changed: a fresh array on every
+    // layout event re-renders the sidebar (and the whole workspace) for nothing.
+    setLocalPanels((prev) =>
+      prev.length === panels.length &&
+      prev.every((panel, i) => panel.id === panels[i].id && panel.title === panels[i].title)
+        ? prev
+        : panels
+    )
   }, [])
 
   /** Recount session panels per dockview into local state. */
@@ -426,6 +479,10 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
         }
         useCount.delete(sid)
         killSession(sid)
+        // No pane shows this session any more: drop its bookkeeping too, so
+        // neither the dead-session set nor the cwd map grows for the whole run.
+        deadSessions.delete(sid)
+        forgetSessionCwd(sid)
       }
 
       const cleanups = [
@@ -522,28 +579,41 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
    * Boot pass: pick up where the user left off — layout plus each pane's
    * directory — when 设置 → 系统 → 启动时恢复上次会话 is on. Otherwise (or when no
    * snapshot exists) seed one terminal. Either way the workspace is never empty.
+   *
+   * Gated on the settings hydrate: reading `restoreSession` before it lands
+   * always sees the defaults, so a user who turned restore off got their session
+   * back whenever the dockview became ready first.
    */
   useEffect(() => {
-    if (!terminalReady) return
+    if (!terminalReady || !settingsHydrated) return
     let cancelled = false
     void (async (): Promise<void> => {
       const current = terminalApiRef.current
       if (!current) return
-      const restoreOn = useSettingsStore.getState().settings.system.restoreSession !== false
-      const snapshot = restoreOn ? await window.api.getSessionState().catch(() => null) : null
-      if (cancelled) return
-      const restorable = Boolean(snapshot && (snapshot.layouts.terminal || snapshot.panels.length > 0))
-      const restored = snapshot && restorable ? await restoreFromSnapshot(snapshot) : false
-      if (cancelled) return
-      if (!restored && !current.panels.some((p) => sessionIdOf(p))) void addTerminal()
-      bootDoneRef.current = true
-      scheduleSave()
+      try {
+        const restoreOn = useSettingsStore.getState().settings.system.restoreSession !== false
+        const snapshot = restoreOn ? await window.api.getSessionState().catch(() => null) : null
+        if (cancelled) return
+        const restorable = Boolean(snapshot && (snapshot.layouts.terminal || snapshot.panels.length > 0))
+        const restored = snapshot && restorable ? await restoreFromSnapshot(snapshot) : false
+        if (cancelled) return
+        if (!restored && !current.panels.some((p) => sessionIdOf(p))) await addTerminal()
+      } catch (error) {
+        // An escaped rejection used to leave the workspace half-applied: the
+        // boot flag never flipped (so no snapshot was ever saved again) and the
+        // panes the pass had not reached stayed bound to dead session ids.
+        console.error('[workspace] session restore failed', error)
+        if (!cancelled) message.error(t('workspace.error.title'))
+      } finally {
+        bootDoneRef.current = true
+        scheduleSave()
+      }
     })()
     return () => {
       cancelled = true
     }
-    // eslint-disable-next-line react-hooks/exhaustive-deps -- boot exactly once, on first ready
-  }, [terminalReady])
+    // eslint-disable-next-line react-hooks/exhaustive-deps -- boot once, on ready + hydrated
+  }, [terminalReady, settingsHydrated])
 
   /** Kill remaining sessions on window close. */
   useEffect(() => {
@@ -649,10 +719,15 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
    * stream; `connectionId` + any staged `secretOverride` are the only inputs
    * the main process needs — no extra IPC channel. New sessions land in the ssh
    * dockview.
+   *
+   * Re-entrant calls are dropped: a double-click would otherwise open two
+   * sessions for one click, and openSession cannot be aborted once it is away.
    */
   const connect = useCallback(
     async (conn: SshConnection, secretOverride: SshSecretOverride): Promise<void> => {
-      setConnecting(true)
+      if (connectInFlightRef.current > 0) return
+      connectInFlightRef.current += 1
+      setConnectingCount((count) => count + 1)
       try {
         const result = await window.api.openSession({
           kind: 'ssh',
@@ -674,9 +749,10 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
         // B's sidebar refreshes lastConnectedAt on connect.
         void sidebarRef.current?.refresh()
       } catch (error) {
-        message.error(typeof error === 'string' ? error : t('workspace.connect.failed'))
+        message.error(connectFailureMessage(error))
       } finally {
-        setConnecting(false)
+        connectInFlightRef.current -= 1
+        setConnectingCount((count) => count - 1)
         setRequestedConn(null)
       }
     },
@@ -685,6 +761,7 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
 
   const handleConnectRequest = useCallback(
     (conn: SshConnection): void => {
+      if (connectInFlightRef.current > 0) return
       // Ask-at-connect connections go through the secret prompt first; saved
       // credentials must connect IMMEDIATELY — routing them through ConnectFlow
       // would only ever *render* a "connecting" spinner without firing openSession.
@@ -694,6 +771,9 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
         setRequestedConn(conn)
         return
       }
+      // Immediate path: show the same uncancellable "连接中" modal the secret
+      // path uses, so the server list is not clickable while openSession flies.
+      setRequestedConn(conn)
       void connect(conn, {})
     },
     [connect]
@@ -783,16 +863,35 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
    * panel's `<TerminalView>` with the new `sessionId` prop exactly the way it
    * does when the user switches terminals — its bind effect tears the old xterm
    * down and replays the new session's output.
+   *
+   * The owning dockview api comes along so the panel's survival can be checked
+   * after the await: a pane closed while its pty was still starting would
+   * otherwise leave that fresh session behind, bound to no panel and never
+   * killed.
    */
   const bindPanelSession = useCallback(
-    async (panel: DockviewPanelApi | undefined, currentSessionId: string, cwd?: string): Promise<void> => {
-      if (!panel) return
-      const nextSessionId = await createSession(cwd)
-      panel.updateParameters({ sessionId: nextSessionId, sessionKind: 'local' })
-      deadSessionsRef.current.delete(currentSessionId)
-      forgetSessionCwd(currentSessionId)
+    async (
+      api: DockviewApi | undefined,
+      panel: DockviewPanelApi | undefined,
+      currentSessionId: string,
+      cwd?: string
+    ): Promise<void> => {
+      if (!api || !panel) return
+      try {
+        const nextSessionId = await createSession(cwd)
+        if (!api.getPanel(panel.id)) {
+          killSession(nextSessionId)
+          forgetSessionCwd(nextSessionId)
+          return
+        }
+        panel.updateParameters({ sessionId: nextSessionId, sessionKind: 'local' })
+        deadSessions.delete(currentSessionId)
+        forgetSessionCwd(currentSessionId)
+      } catch (error) {
+        console.error('[workspace] panel rebind failed', error)
+      }
     },
-    [createSession]
+    [createSession, killSession]
   )
 
   /**
@@ -836,7 +935,13 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
           panel.api.close()
           continue
         }
-        await bindPanelSession(panel.api, id, lookup(panel.id)?.cwd)
+        // One pane failing to rebind must not abort the panes after it (they
+        // would keep the stale session id of a previous launch and stay dead).
+        try {
+          await bindPanelSession(api, panel.api, id, lookup(panel.id)?.cwd)
+        } catch (error) {
+          console.error('[workspace] pane rebind failed', panel.id, error)
+        }
       }
     },
     [bindPanelSession]
@@ -879,8 +984,13 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
       // Retitle duplicates left over from the old counter bug (the snapshot it
       // wrote keeps colliding titles forever otherwise): the first panel keeps
       // the title, later ones get the lowest free number.
+      //
+      // Local terminals only: an SSH pane is titled with its server name, and a
+      // split deliberately shares that title with its sibling, so the terminal
+      // numbering pattern is the wrong remedy there.
       const seenTitles = new Set<string>()
       for (const p of [...(terminal?.panels ?? []), ...(ssh?.panels ?? [])]) {
+        if ((p.params as TerminalParams | undefined)?.sessionKind === 'ssh') continue
         const t = p.title ?? ''
         if (!t) continue
         if (seenTitles.has(t)) {
@@ -1014,19 +1124,11 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
           <div className={workspaceMode === 'terminal' ? 'workspace-dockview-container' : 'workspace-dockview-container is-hidden'}>
             <DockviewReact
               className="dockview-theme-abyss"
-              components={{
-                [TERMINAL_COMPONENT]: (props: IDockviewPanelProps<TerminalParams>) => (
-                  <TerminalPanel {...props} onSessionDead={markSessionDead} />
-                )
-              }}
-              tabComponents={{
-                [TERMINAL_TAB_COMPONENT]: (props: IDockviewPanelHeaderProps<TerminalParams>) => (
-                  <TerminalTab {...props} />
-                )
-              }}
+              components={DOCKVIEW_COMPONENTS}
+              tabComponents={DOCKVIEW_TAB_COMPONENTS}
               rightHeaderActionsComponent={TerminalTabActions}
               onReady={handleTerminalReady}
-              theme={{ name: 'Abyss', className: 'dockview-theme-abyss', colorScheme: 'dark' }}
+              theme={DOCKVIEW_THEME}
             />
             {terminalCount === 0 && (
               <div className="workspace-empty-overlay">
@@ -1048,19 +1150,11 @@ export default function Workspace({ onOpenSettings }: WorkspaceProps): React.JSX
           <div className={workspaceMode === 'ssh' ? 'workspace-dockview-container' : 'workspace-dockview-container is-hidden'}>
             <DockviewReact
               className="dockview-theme-abyss"
-              components={{
-                [TERMINAL_COMPONENT]: (props: IDockviewPanelProps<TerminalParams>) => (
-                  <TerminalPanel {...props} onSessionDead={markSessionDead} />
-                )
-              }}
-              tabComponents={{
-                [TERMINAL_TAB_COMPONENT]: (props: IDockviewPanelHeaderProps<TerminalParams>) => (
-                  <TerminalTab {...props} />
-                )
-              }}
+              components={DOCKVIEW_COMPONENTS}
+              tabComponents={DOCKVIEW_TAB_COMPONENTS}
               rightHeaderActionsComponent={SshTabActions}
               onReady={handleSshReady}
-              theme={{ name: 'Abyss', className: 'dockview-theme-abyss', colorScheme: 'dark' }}
+              theme={DOCKVIEW_THEME}
             />
             {sshCount === 0 && (
               <div className="workspace-empty-overlay">

src/renderer/src/workspace/ZmodemOffers.tsx

@@ -83,6 +83,16 @@ export default function ZmodemOffers(): null | React.JSX.Element {
 
   const offDone = useCallback(
     (evt: { id: string; ok: boolean; message?: string }) => {
+      // The offer can be finished by main without an answer — its 120s watchdog
+      // aborts it and reports ok:false. Drop the entry either way, otherwise a
+      // dead offer keeps an unclosable modal (and its busy flag) alive.
+      busyRef.current.delete(evt.id)
+      setOffers((prev) => {
+        if (!prev.has(evt.id)) return prev
+        const next = new Map(prev)
+        next.delete(evt.id)
+        return next
+      })
       if (evt.ok) message.success(t('ssh.zmodem.done'))
       else
         message.error(

src/renderer/src/workspace/broadcastStore.ts

@@ -2,10 +2,17 @@ import { create } from 'zustand'
 
 /** One open terminal session eligible to be a broadcast target. */
 export interface BroadcastSession {
-  /** pty / ssh session id (also the dockview panel id) */
+  /** pty / ssh session id */
   id: string
   title: string
   isSsh: boolean
+  /**
+   * dockview panel showing this session. One session can back several panels —
+   * an SSH split deliberately mirrors a single session — so registrations are
+   * keyed by panel: closing one pane must not unregister the pane that is still
+   * showing that session.
+   */
+  panelId: string
 }
 
 export interface BroadcastState {
@@ -15,10 +22,13 @@ export interface BroadcastState {
   targets: Set<string>
   /** open terminal sessions, registration order preserved */
   sessions: BroadcastSession[]
-  /** register a session as broadcast-eligible (idempotent, keeps it fresh) */
+  /** register a panel's session as broadcast-eligible (upsert, keeps it fresh) */
   registerSession: (session: BroadcastSession) => void
-  /** remove a session; if it was a target, prune it (may auto-disable <2 targets) */
-  unregisterSession: (id: string) => void
+  /**
+   * drop one panel's registration; the session leaves `sessions` (and the
+   * targets, possibly auto-disabling) only once no panel shows it any more
+   */
+  unregisterSession: (panelId: string) => void
   /** add/remove one target; never lets the set drop below 2 while enabled */
   toggleTarget: (id: string) => void
   /** turn broadcast on/off */
@@ -43,29 +53,42 @@ function pruneOnTargetLoss(enabled: boolean, nextTargets: Set<string>): { enable
   return { enabled, targets: nextTargets }
 }
 
+/**
+ * panelId → registration. The session list is derived from these rather than
+ * maintained alongside them: one session can back several panels (an SSH split
+ * mirrors a single session on purpose), and only the last panel to unmount may
+ * take the session out of the registry.
+ */
+const registrations = new Map<string, BroadcastSession>()
+
+/** One entry per session, in first-registration order, latest title wins. */
+function deriveSessions(): BroadcastSession[] {
+  const bySession = new Map<string, BroadcastSession>()
+  for (const registration of registrations.values()) bySession.set(registration.id, registration)
+  return [...bySession.values()]
+}
+
 export const useBroadcastStore = create<BroadcastState>((set) => ({
   enabled: false,
   targets: new Set(),
   sessions: [],
 
-  registerSession: (session) =>
-    set((state) => {
-      const exists = state.sessions.some((s) => s.id === session.id)
-      if (exists) {
-        // keep title/isSsh fresh (e.g. template apply retitles a panel)
-        const sessions = state.sessions.map((s) => (s.id === session.id ? session : s))
-        const targets = new Set(state.targets)
-        return { sessions, targets }
-      }
-      return { sessions: [...state.sessions, session] }
-    }),
+  registerSession: (session) => {
+    registrations.set(session.panelId, session)
+    set({ sessions: deriveSessions() })
+  },
 
-  unregisterSession: (id) =>
+  unregisterSession: (panelId) =>
     set((state) => {
-      const sessions = state.sessions.filter((s) => s.id !== id)
-      if (!state.targets.has(id)) return { sessions }
+      const dropped = registrations.get(panelId)
+      if (!dropped) return {}
+      registrations.delete(panelId)
+      const sessions = deriveSessions()
+      // another pane still shows this session — keep it, and its target slot
+      if (sessions.some((s) => s.id === dropped.id)) return { sessions }
+      if (!state.targets.has(dropped.id)) return { sessions }
       const targets = new Set(state.targets)
-      targets.delete(id)
+      targets.delete(dropped.id)
       return { sessions, ...pruneOnTargetLoss(state.enabled, targets) }
     }),
 
@@ -74,7 +97,11 @@ export const useBroadcastStore = create<BroadcastState>((set) => ({
       const targets = new Set(state.targets)
       if (targets.has(id)) {
         targets.delete(id)
-        return pruneOnTargetLoss(state.enabled, targets)
+        // Deliberate uncheck: keep the remaining selection — broadcast just
+        // turns off below the 2-target minimum. Only session loss (see
+        // unregisterSession) may wipe the set.
+        if (targets.size < 2) return { enabled: false, targets }
+        return { enabled: state.enabled, targets }
       }
       targets.add(id)
       // requires >= 2 targets to become/become-enabled