feat(desktop): remember window size/position/maximized across launches (salvage #39154)

The desktop window opened at a hardcoded 1220×800 every launch, discarding
whatever size and position the user left it at (#39101) — on macOS the dock
reopen was the most visible case, but every restart reset it.

A small window-state.json under userData (same pattern as connection.json /
updates.json) records the window's normal bounds plus its maximized flag,
written debounced on resize/move/maximize and flushed on close, applied on the
next createWindow(). getNormalBounds() captures the pre-maximize size so an
un-maximize next session lands where the user actually sized it.

Restore is defensive: sanitize rejects garbage, drops off-screen positions
(window falls back to Electron centering), and caps a size saved on a
since-disconnected larger monitor to the largest current display. The geometry
math lives in a side-effect-free window-state.cjs so it unit-tests with
node --test, no Electron boot. No new dependency.

Salvages #39154 by @jeffrobodie-glitch — same userData approach and validation
intent, reimplemented tighter and folded into one module.

Co-authored-by: jeffrobodie-glitch <jeffrobodie@gmail.com>

apps/desktop/electron/main.cjs

@@ -12,6 +12,7 @@ const {
   powerMonitor,
   protocol,
   safeStorage,
+  screen,
   session,
   shell,
   systemPreferences
@@ -67,6 +68,13 @@ const {
   uninstallArgsForMode
 } = require('./desktop-uninstall.cjs')
 const { isPackagedInstallPath: isPackagedInstallPathUnderRoots } = require('./workspace-cwd.cjs')
+const {
+  MIN_WIDTH: WINDOW_MIN_WIDTH,
+  MIN_HEIGHT: WINDOW_MIN_HEIGHT,
+  sanitizeWindowState,
+  computeWindowOptions,
+  debounce
+} = require('./window-state.cjs')
 const {
   authModeFromStatus,
   buildGatewayWsUrl,
@@ -320,6 +328,7 @@ const BOOTSTRAP_MARKER_SCHEMA_VERSION = 1
 
 const DESKTOP_CONNECTION_CONFIG_PATH = path.join(app.getPath('userData'), 'connection.json')
 const DESKTOP_UPDATE_CONFIG_PATH = path.join(app.getPath('userData'), 'updates.json')
+const DESKTOP_WINDOW_STATE_PATH = path.join(app.getPath('userData'), 'window-state.json')
 // active-profile.json records which Hermes profile the desktop launches its
 // local backend as. When set, startHermes() passes `hermes --profile <name>
 // dashboard …`, which deterministically pins HERMES_HOME (see
@@ -1522,6 +1531,36 @@ function writeDesktopUpdateConfig(config) {
   writeFileAtomic(DESKTOP_UPDATE_CONFIG_PATH, JSON.stringify(config, null, 2))
 }
 
+// ─── Main-window geometry persistence (window-state.json) ──────────────────
+
+function readWindowState() {
+  try {
+    return sanitizeWindowState(JSON.parse(fs.readFileSync(DESKTOP_WINDOW_STATE_PATH, 'utf8')))
+  } catch {
+    return null
+  }
+}
+
+// Persist the window's restored (non-maximized) bounds plus its maximized flag.
+// getNormalBounds() keeps the pre-maximize size, so un-maximizing next session
+// lands back where the user actually sized the window.
+function persistWindowState() {
+  if (!mainWindow || mainWindow.isDestroyed() || mainWindow.isMinimized()) return
+  try {
+    const { x, y, width, height } = mainWindow.getNormalBounds()
+    fs.mkdirSync(path.dirname(DESKTOP_WINDOW_STATE_PATH), { recursive: true })
+    writeFileAtomic(
+      DESKTOP_WINDOW_STATE_PATH,
+      JSON.stringify({ x, y, width, height, isMaximized: mainWindow.isMaximized() }, null, 2)
+    )
+  } catch (err) {
+    rememberLog(`[window-state] persist failed: ${err?.message || err}`)
+  }
+}
+
+// resized/moved fire many times mid-drag on Linux; debounce to one write.
+const schedulePersistWindowState = debounce(persistWindowState, 250)
+
 // Match the backend's source resolution but bias toward a real git checkout.
 // Dev → SOURCE_REPO_ROOT. Packaged/CLI install → ACTIVE_HERMES_ROOT.
 // HERMES_DESKTOP_HERMES_ROOT always wins so devs can pin a worktree.
@@ -5523,11 +5562,11 @@ function closePetOverlay() {
 
 function createWindow() {
   const icon = getAppIconPath()
+  const savedWindowState = readWindowState()
   mainWindow = new BrowserWindow({
-    width: 1220,
-    height: 800,
-    minWidth: 400,
-    minHeight: 620,
+    ...computeWindowOptions(savedWindowState, screen.getAllDisplays()),
+    minWidth: WINDOW_MIN_WIDTH,
+    minHeight: WINDOW_MIN_HEIGHT,
     title: 'Hermes',
     // Frameless title bar on every platform so the renderer can paint the
     // "hide sidebar" button (and other left-side titlebar tools) flush with
@@ -5569,6 +5608,8 @@ function createWindow() {
     }
   }
 
+  if (savedWindowState?.isMaximized) mainWindow.maximize()
+
   mainWindow.once('ready-to-show', () => {
     if (mainWindow && !mainWindow.isDestroyed()) mainWindow.show()
   })
@@ -5578,6 +5619,14 @@ function createWindow() {
   mainWindow.on('will-leave-full-screen', () => sendWindowStateChanged(false))
   mainWindow.on('leave-full-screen', () => sendWindowStateChanged(false))
 
+  // Reopen where the user left off. resized/moved settle once per drag; close is
+  // the cross-platform backstop, flushed synchronously before the window is gone.
+  mainWindow.on('resized', schedulePersistWindowState)
+  mainWindow.on('moved', schedulePersistWindowState)
+  mainWindow.on('maximize', schedulePersistWindowState)
+  mainWindow.on('unmaximize', schedulePersistWindowState)
+  mainWindow.on('close', () => schedulePersistWindowState.flush())
+
   // The overlay rides the main window — closing the app's primary window must
   // tear it down too (otherwise it strands as an orphan that blocks
   // window-all-closed from quitting on Windows/Linux).

apps/desktop/electron/window-state.cjs

@@ -0,0 +1,117 @@
+/**
+ * Pure geometry helpers for window-state.json — restoring the main window's
+ * size, position, and maximized flag across launches. Side-effect-free so the
+ * part that actually matters (rejecting garbage + off-screen bounds) is
+ * unit-testable without booting Electron; main.cjs owns the file I/O and the
+ * live `screen` displays.
+ */
+
+// Defaults mirror the historical hardcoded BrowserWindow size; MIN_* mirror its
+// minWidth/minHeight so a restored size never undershoots what the live window
+// allows. A fresh install (no saved state) is byte-identical to before.
+const DEFAULT_WIDTH = 1220
+const DEFAULT_HEIGHT = 800
+const MIN_WIDTH = 400
+const MIN_HEIGHT = 620
+
+// Keep at least this much of the window over a display work area before we trust
+// a saved position, so the title bar stays grabbable after a monitor unplugs.
+const MIN_VISIBLE = 48
+
+const finite = v => typeof v === 'number' && Number.isFinite(v)
+const clamp = (v, lo, hi) => Math.max(lo, Math.min(v, hi))
+
+// Parse raw JSON → clean state, or null if garbage. width/height are required
+// and floored; x/y survive only as a finite pair; isMaximized is strict.
+function sanitizeWindowState(raw) {
+  if (!raw || typeof raw !== 'object' || !finite(raw.width) || !finite(raw.height)) return null
+
+  const state = {
+    width: Math.max(MIN_WIDTH, Math.round(raw.width)),
+    height: Math.max(MIN_HEIGHT, Math.round(raw.height)),
+    isMaximized: raw.isMaximized === true
+  }
+  if (finite(raw.x) && finite(raw.y)) {
+    state.x = Math.round(raw.x)
+    state.y = Math.round(raw.y)
+  }
+  return state
+}
+
+// True when `bounds` overlaps some display's work area by ≥ MIN_VISIBLE on both
+// axes. `displays` is Electron's screen.getAllDisplays() shape.
+function onScreen(bounds, displays) {
+  if (!Array.isArray(displays)) return false
+  return displays.some(({ workArea: a } = {}) => {
+    if (!a) return false
+    const x = Math.min(bounds.x + bounds.width, a.x + a.width) - Math.max(bounds.x, a.x)
+    const y = Math.min(bounds.y + bounds.height, a.y + a.height) - Math.max(bounds.y, a.y)
+    return x >= MIN_VISIBLE && y >= MIN_VISIBLE
+  })
+}
+
+// Sanitized state (or null) → BrowserWindow size/position options. Always sets
+// width/height, capped to the largest current display so a size saved on a
+// since-disconnected bigger monitor can't exceed any screen the user now has.
+// Sets x/y only when still on-screen; otherwise Electron centers the window.
+function computeWindowOptions(state, displays) {
+  const opts = {
+    width: finite(state?.width) ? state.width : DEFAULT_WIDTH,
+    height: finite(state?.height) ? state.height : DEFAULT_HEIGHT
+  }
+
+  const cap = (Array.isArray(displays) ? displays : []).reduce(
+    (m, { workArea: a } = {}) =>
+      a && finite(a.width) && finite(a.height)
+        ? { width: Math.max(m.width, a.width), height: Math.max(m.height, a.height) }
+        : m,
+    { width: 0, height: 0 }
+  )
+  if (cap.width && cap.height) {
+    opts.width = clamp(opts.width, MIN_WIDTH, cap.width)
+    opts.height = clamp(opts.height, MIN_HEIGHT, cap.height)
+  }
+
+  if (
+    state &&
+    finite(state.x) &&
+    finite(state.y) &&
+    onScreen({ x: state.x, y: state.y, width: opts.width, height: opts.height }, displays)
+  ) {
+    opts.x = state.x
+    opts.y = state.y
+  }
+  return opts
+}
+
+// Trailing debounce: collapse a burst of resize/move events (Linux fires many
+// mid-drag) into a single run `delayMs` after the last. `.flush()` runs now and
+// cancels the pending timer — used on close, before the window is gone.
+function debounce(fn, delayMs) {
+  let timer = null
+  const debounced = () => {
+    clearTimeout(timer)
+    timer = setTimeout(() => {
+      timer = null
+      fn()
+    }, delayMs)
+  }
+  debounced.flush = () => {
+    clearTimeout(timer)
+    timer = null
+    fn()
+  }
+  return debounced
+}
+
+module.exports = {
+  DEFAULT_WIDTH,
+  DEFAULT_HEIGHT,
+  MIN_WIDTH,
+  MIN_HEIGHT,
+  MIN_VISIBLE,
+  sanitizeWindowState,
+  onScreen,
+  computeWindowOptions,
+  debounce
+}

apps/desktop/electron/window-state.test.cjs

@@ -0,0 +1,135 @@
+/**
+ * Unit tests for the pure window-state geometry helpers. These cover the logic
+ * that protects the user: garbage rejection, off-screen fallback, oversized
+ * clamping, and the debounce that collapses mid-drag write storms.
+ */
+
+const test = require('node:test')
+const assert = require('node:assert/strict')
+
+const {
+  DEFAULT_WIDTH,
+  DEFAULT_HEIGHT,
+  MIN_WIDTH,
+  MIN_HEIGHT,
+  sanitizeWindowState,
+  onScreen,
+  computeWindowOptions,
+  debounce
+} = require('./window-state.cjs')
+
+// A single 1920×1080 monitor (work area trimmed for the taskbar).
+const PRIMARY = [{ workArea: { x: 0, y: 0, width: 1920, height: 1040 } }]
+// A laptop panel left behind after a bigger external monitor is unplugged.
+const LAPTOP = [{ workArea: { x: 0, y: 0, width: 1366, height: 728 } }]
+
+// ─── sanitizeWindowState ───────────────────────────────────────────────────
+
+test('sanitizeWindowState rejects missing/garbage input', () => {
+  for (const bad of [null, undefined, 'nope', 42, {}, { width: 'x', height: 800 }, { width: NaN, height: 800 }, { width: 1000 }]) {
+    assert.equal(sanitizeWindowState(bad), null)
+  }
+})
+
+test('sanitizeWindowState keeps a valid full state and rounds HiDPI fractions', () => {
+  assert.deepEqual(sanitizeWindowState({ x: 100.6, y: 50.2, width: 1400.4, height: 900.7, isMaximized: true }), {
+    x: 101,
+    y: 50,
+    width: 1400,
+    height: 901,
+    isMaximized: true
+  })
+})
+
+test('sanitizeWindowState floors size to the minimums', () => {
+  const state = sanitizeWindowState({ width: 10, height: 10 })
+  assert.equal(state.width, MIN_WIDTH)
+  assert.equal(state.height, MIN_HEIGHT)
+})
+
+test('sanitizeWindowState drops a partial position but keeps the size', () => {
+  assert.deepEqual(sanitizeWindowState({ x: 100, width: 1400, height: 900 }), {
+    width: 1400,
+    height: 900,
+    isMaximized: false
+  })
+})
+
+test('sanitizeWindowState treats isMaximized strictly', () => {
+  assert.equal(sanitizeWindowState({ width: 1400, height: 900, isMaximized: 'yes' }).isMaximized, false)
+})
+
+// ─── onScreen ──────────────────────────────────────────────────────────────
+
+test('onScreen accepts a window on the primary or a secondary display', () => {
+  const dual = [...PRIMARY, { workArea: { x: 1920, y: 0, width: 2560, height: 1400 } }]
+  assert.equal(onScreen({ x: 100, y: 100, width: 1220, height: 800 }, PRIMARY), true)
+  assert.equal(onScreen({ x: 2200, y: 200, width: 1220, height: 800 }, dual), true)
+})
+
+test('onScreen rejects off-screen, slivers, and bad input', () => {
+  assert.equal(onScreen({ x: 3000, y: 100, width: 1220, height: 800 }, PRIMARY), false) // past right edge
+  assert.equal(onScreen({ x: 100, y: -900, width: 1220, height: 800 }, PRIMARY), false) // above top
+  assert.equal(onScreen({ x: 1910, y: 100, width: 1220, height: 800 }, PRIMARY), false) // ~10px sliver
+  assert.equal(onScreen({ x: 0, y: 0, width: 1220, height: 800 }, []), false)
+  assert.equal(onScreen({ x: 0, y: 0, width: 1220, height: 800 }, null), false)
+})
+
+// ─── computeWindowOptions ──────────────────────────────────────────────────
+
+test('computeWindowOptions falls back to defaults with no saved state', () => {
+  assert.deepEqual(computeWindowOptions(null, PRIMARY), { width: DEFAULT_WIDTH, height: DEFAULT_HEIGHT })
+})
+
+test('computeWindowOptions restores an on-screen position', () => {
+  const saved = sanitizeWindowState({ x: 200, y: 150, width: 1400, height: 900 })
+  assert.deepEqual(computeWindowOptions(saved, PRIMARY), { width: 1400, height: 900, x: 200, y: 150 })
+})
+
+test('computeWindowOptions keeps the size but drops an off-screen position', () => {
+  const saved = sanitizeWindowState({ x: 5000, y: 150, width: 1400, height: 900 })
+  assert.deepEqual(computeWindowOptions(saved, PRIMARY), { width: 1400, height: 900 })
+})
+
+test('computeWindowOptions clamps a size larger than the only display', () => {
+  const saved = sanitizeWindowState({ width: 2560, height: 1440 })
+  assert.deepEqual(computeWindowOptions(saved, LAPTOP), { width: 1366, height: 728 })
+})
+
+test('computeWindowOptions keeps the MIN floor on a sub-minimum display', () => {
+  const tiny = [{ workArea: { x: 0, y: 0, width: 360, height: 480 } }]
+  const saved = sanitizeWindowState({ width: 2000, height: 1500 })
+  assert.deepEqual(computeWindowOptions(saved, tiny), { width: MIN_WIDTH, height: MIN_HEIGHT })
+})
+
+test('computeWindowOptions does not clamp when displays are unknown', () => {
+  const saved = sanitizeWindowState({ width: 2560, height: 1440 })
+  assert.deepEqual(computeWindowOptions(saved, []), { width: 2560, height: 1440 })
+})
+
+// ─── debounce ──────────────────────────────────────────────────────────────
+
+test('debounce coalesces a burst into one trailing run', t => {
+  t.mock.timers.enable({ apis: ['setTimeout'] })
+  let calls = 0
+  const d = debounce(() => { calls += 1 }, 250)
+
+  d(); d(); d()
+  assert.equal(calls, 0)
+  t.mock.timers.tick(249)
+  assert.equal(calls, 0)
+  t.mock.timers.tick(1)
+  assert.equal(calls, 1)
+})
+
+test('debounce.flush runs now and cancels the pending timer', t => {
+  t.mock.timers.enable({ apis: ['setTimeout'] })
+  let calls = 0
+  const d = debounce(() => { calls += 1 }, 250)
+
+  d()
+  d.flush()
+  assert.equal(calls, 1)
+  t.mock.timers.tick(1000)
+  assert.equal(calls, 1)
+})

apps/desktop/package.json

@@ -37,7 +37,7 @@
     "test:desktop:nsis": "node scripts/test-desktop.mjs nsis",
     "test:desktop:existing": "node scripts/test-desktop.mjs existing",
     "test:desktop:fresh": "node scripts/test-desktop.mjs fresh",
-    "test:desktop:platforms": "node --test electron/bootstrap-platform.test.cjs electron/hardening.test.cjs electron/backend-env.test.cjs electron/backend-probes.test.cjs electron/backend-ready.test.cjs electron/bootstrap-runner.test.cjs electron/connection-config.test.cjs electron/dashboard-token.test.cjs electron/gateway-ws-probe.test.cjs electron/oauth-net-request.test.cjs electron/desktop-uninstall.test.cjs electron/session-windows.test.cjs electron/link-title-window.test.cjs electron/workspace-cwd.test.cjs electron/fs-read-dir.test.cjs electron/git-root.test.cjs electron/windows-child-process.test.cjs electron/update-remote.test.cjs electron/update-rebuild.test.cjs electron/update-marker.test.cjs electron/update-relaunch.test.cjs electron/windows-user-env.test.cjs",
+    "test:desktop:platforms": "node --test electron/bootstrap-platform.test.cjs electron/hardening.test.cjs electron/backend-env.test.cjs electron/backend-probes.test.cjs electron/backend-ready.test.cjs electron/bootstrap-runner.test.cjs electron/connection-config.test.cjs electron/dashboard-token.test.cjs electron/gateway-ws-probe.test.cjs electron/oauth-net-request.test.cjs electron/desktop-uninstall.test.cjs electron/session-windows.test.cjs electron/link-title-window.test.cjs electron/workspace-cwd.test.cjs electron/fs-read-dir.test.cjs electron/git-root.test.cjs electron/windows-child-process.test.cjs electron/update-remote.test.cjs electron/update-rebuild.test.cjs electron/update-marker.test.cjs electron/update-relaunch.test.cjs electron/windows-user-env.test.cjs electron/window-state.test.cjs",
     "typecheck": "tsc -p . --noEmit",
     "lint": "eslint src/ electron/",
     "lint:fix": "eslint src/ electron/ --fix",