Merge pull request #55 from LINUXexpert-org/settings-server-side

Keep settings with the account, not the browser

README.md

@@ -83,6 +83,7 @@ seconds of downtime with nothing lost.
 - **Self-service credentials** in Settings › Security: change your password, manage **app passwords** (a separate password per mail app or device, revocable on its own), and turn **two-factor authentication** on or off by scanning a QR code. Enrolment codes are verified before anything is stored, so a mistyped key cannot lock you out, and switching 2FA on moves this browser's session onto a dedicated app password instead of signing you straight back out. Works against both Stalwart generations: the `x:AccountPassword` / `x:AppPassword` registry objects on 0.16+, and the `/api/account/auth` REST endpoint on 0.15.x (the latter confirmed live)
 - **Light and dark** follow the system by default, with a toggle in the top bar for flipping between them and a three-way choice in Settings › Appearance
 - Identities & signatures, **Sieve filters** (visual rule builder that round-trips to a Sieve script, plus a raw script editor with server-side validation), out-of-office (`VacationResponse`), folders, labels, templates, notifications, calendar defaults, sessions (sign out other devices), keyboard shortcuts, import/export of settings
+- **Settings follow the account, not the browser** (Stalwart 0.16+): they are kept in a `settings.json` in the account's own JMAP Files, so the default identity, locale, date and time formats, theme, labels, templates, folder colours and the rest are the same wherever you sign in — including a private window. ihasmail still stores nothing itself; the file lives in the mail store and is backed up with it. Settings that describe *this* screen or browser stay local, because syncing them would be wrong rather than helpful: list-pane sizes, density, font size, sidebar state, and the notification toggles (which track a permission the browser grants per-device). localStorage is kept as a cache so the first frame is already right, and the file corrects it a moment later. On Stalwart 0.15 nothing changes — settings stay local, as before
 
 **Platform**
 - Installable PWA (manifest + service worker), mobile layout with bottom tab bar, drawer navigation, full-screen composer, FAB
@@ -101,7 +102,7 @@ browser  ──(same-origin /api/*)──►  ihasmail server (Node + Hono)  ─
 - `web/` — Vite + React 19 + TypeScript SPA. `src/jmap` (client, push, types), `src/store` (zustand stores: session, mail, compose, contacts, calendar, files, sieve, settings), `src/views` (mail, compose, calendar, contacts, files, settings), `src/lib` (sanitiser, search parser, Sieve codec, dates and locale-aware formatting, vCard, …).
 - `server/` — tiny Node/Hono backend: authenticates against Stalwart's JMAP session endpoint, stores the credentials sealed with a key derived from the cookie secret (the server never persists plaintext passwords), proxies JMAP/blob/SSE calls, serves the SPA with a strict CSP. Also contains `src/mock/` — an in-memory fake Stalwart for local development and demos.
 
-Stalwart capabilities used: `core`, `mail`, `submission`, `vacationresponse`, `sieve`, `contacts`(+`parse`), `calendars`(+`parse`), `principals`(+`availability`), `quota`, `blob`, `filenode`, EventSource push, plus Stalwart's own `urn:stalwart:jmap` (read-only, for the account locale). Features degrade gracefully when a capability is missing.
+Stalwart capabilities used: `core`, `mail`, `submission`, `vacationresponse`, `sieve`, `contacts`(+`parse`), `calendars`(+`parse`), `principals`(+`availability`), `quota`, `blob`, `filenode`, EventSource push, plus Stalwart's own `urn:stalwart:jmap` (read-only, for the account locale and to tell the generations apart). Features degrade gracefully when a capability is missing.
 
 ## Quick start (Docker)
 

web/src/App.tsx

@@ -17,7 +17,8 @@ import { AppShell } from "@/views/AppShell";
 import { MailView } from "@/views/mail/MailView";
 import { ComposerDock } from "@/views/compose/ComposerDock";
 import { setUnreadBadge } from "@/lib/notify";
-import { useSettings } from "@/store/settings";
+import { useSettings, syncedPart } from "@/store/settings";
+import { armSettingsSync, loadRemoteSettings, queueSettingsPush, settingsSyncAvailable } from "@/lib/settingsSync";
 
 const ContactsView = lazy(() => import("@/views/contacts/ContactsView").then((m) => ({ default: m.ContactsView })));
 const CalendarView = lazy(() => import("@/views/calendar/CalendarView").then((m) => ({ default: m.CalendarView })));
@@ -51,6 +52,26 @@ function AuthedApp() {
   const accountId = useSession((s) => s.accountId);
   const [location] = useLocation();
 
+  // Settings that live with the account rather than the browser. The cached
+  // ones have already painted, so this only has to correct them (issue #54).
+  useEffect(() => {
+    if (!accountId) return;
+    let cancelled = false;
+    void (async () => {
+      const remote = await loadRemoteSettings();
+      if (cancelled) return;
+      if (remote) useSettings.getState().hydrate(remote);
+      // Pushes were held back until now so they could not race the load.
+      armSettingsSync();
+      // No file yet — seed one from what this browser has, so the next device
+      // to sign in starts from these rather than from the defaults.
+      if (!remote && settingsSyncAvailable()) queueSettingsPush(syncedPart(useSettings.getState().settings));
+    })();
+    return () => {
+      cancelled = true;
+    };
+  }, [accountId]);
+
   // Initial data + push wiring
   useEffect(() => {
     if (!accountId) return;

web/src/lib/__tests__/settingsSync.test.ts

@@ -0,0 +1,83 @@
+import { describe, expect, it } from "vitest";
+import { DEFAULT_SETTINGS, DEVICE_KEYS, acceptRemote, syncedPart, type Settings } from "@/store/settings";
+import { isAppFolder } from "../appFolder";
+
+/**
+ * Settings used to live only in localStorage, so nothing followed the user
+ * between devices — issue #54, whose sharpest case is the default identity:
+ * with none set, the address that sorts first wins, so mail goes out from an
+ * address the recipient may not recognise.
+ *
+ * The split is written as a list of exceptions, which means the interesting
+ * test is not "does this key sync" but "does a key added later sync without
+ * anyone remembering to add it".
+ */
+
+describe("which settings follow the account", () => {
+  it("syncs everything that is not explicitly device-local", () => {
+    const synced = syncedPart(DEFAULT_SETTINGS);
+    const expected = (Object.keys(DEFAULT_SETTINGS) as Array<keyof Settings>).filter((k) => !DEVICE_KEYS.has(k));
+    expect(Object.keys(synced).sort()).toEqual(expected.sort());
+  });
+
+  it("keeps this screen's and this browser's settings out of the file", () => {
+    const synced = syncedPart(DEFAULT_SETTINGS);
+    // A pane width picked on a monitor is wrong on a laptop, and the
+    // notification toggles track a per-browser permission grant.
+    for (const key of ["listPaneWidth", "listPaneHeight", "density", "fontSize", "sidebarCollapsed", "desktopNotifications", "notificationSound"]) {
+      expect(synced, key).not.toHaveProperty(key);
+    }
+  });
+
+  it("syncs the default identity, which is what #54 was actually about", () => {
+    const settings: Settings = { ...DEFAULT_SETTINGS, defaultIdentityByAccount: { a1: "i7" } };
+    expect(syncedPart(settings).defaultIdentityByAccount).toEqual({ a1: "i7" });
+  });
+
+  it("syncs theme and reading pane", () => {
+    const synced = syncedPart({ ...DEFAULT_SETTINGS, theme: "dark", readingPane: "bottom" });
+    expect(synced.theme).toBe("dark");
+    expect(synced.readingPane).toBe("bottom");
+  });
+});
+
+describe("applying a settings file", () => {
+  it("takes known, non-device keys", () => {
+    const applied = acceptRemote({ theme: "dark", weekStart: 0, locale: "de-DE" });
+    expect(applied).toEqual({ theme: "dark", weekStart: 0, locale: "de-DE" });
+  });
+
+  it("ignores keys it has never heard of", () => {
+    // A newer ihasmail's settings, or a hand-edited file.
+    expect(acceptRemote({ theme: "dark", somethingNewer: 42 })).toEqual({ theme: "dark" });
+  });
+
+  it("refuses device keys even when the file carries them", () => {
+    // An earlier build wrote the whole settings object up; that file must not
+    // now drag one machine's pane width onto every other one.
+    expect(acceptRemote({ theme: "dark", listPaneWidth: 900, fontSize: "large" })).toEqual({ theme: "dark" });
+  });
+
+  it("does not invent keys from an empty file", () => {
+    expect(acceptRemote({})).toEqual({});
+  });
+
+  it("keeps a false or zero value, which is not the same as absent", () => {
+    const applied = acceptRemote({ conversationMode: false, markReadDelay: 0 });
+    expect(applied).toEqual({ conversationMode: false, markReadDelay: 0 });
+  });
+});
+
+describe("the client's own folder", () => {
+  it("is the top-level ihasmail directory", () => {
+    expect(isAppFolder({ name: "ihasmail", parentId: null, nodeType: "directory" })).toBe(true);
+  });
+
+  it("is not a folder of that name someone made inside another one", () => {
+    expect(isAppFolder({ name: "ihasmail", parentId: "n1", nodeType: "directory" })).toBe(false);
+  });
+
+  it("is not a file that happens to be called that", () => {
+    expect(isAppFolder({ name: "ihasmail", parentId: null, nodeType: "file" })).toBe(false);
+  });
+});

web/src/lib/appFolder.ts

@@ -0,0 +1,91 @@
+/**
+ * The `ihasmail` folder in JMAP Files, where the client keeps its own state:
+ * signature images and over-sized signature HTML (Stalwart caps a signature at
+ * 2 KB), and the synced settings file.
+ *
+ * It is a real folder in the user's account — that is the whole point, since it
+ * is what makes this state travel between devices without ihasmail storing
+ * anything server-side of its own — but it is housekeeping rather than
+ * something anyone filed there, so the Files view hides it. See `isAppFolder`.
+ */
+import { client, setErrorMessage } from "@/jmap/client";
+import type { FileNode, GetResponse, Id, SetResponse } from "@/jmap/types";
+import { directoryCreate, normalizeFileNodes, queryOmitsDirectories, supportsNodeType } from "@/lib/filenode";
+
+export const APP_FOLDER = "ihasmail";
+
+/** Just enough to find the folder, asking for nodeType only where it exists. */
+export const folderProps = (): string[] =>
+  supportsNodeType() ? ["id", "name", "nodeType", "parentId"] : ["id", "name", "parentId", "blobId", "size", "type"];
+
+/** The client's own folder, which the Files view does not show. */
+export function isAppFolder(n: Pick<FileNode, "name" | "parentId" | "nodeType">): boolean {
+  return n.name === APP_FOLDER && !n.parentId && n.nodeType === "directory";
+}
+
+/** Every node in the account, for servers whose query cannot see directories. */
+async function allNodes(accountId: Id, properties: string[]): Promise<FileNode[]> {
+  const res = await client.call<GetResponse<FileNode>>("FileNode/get", { accountId, ids: null, properties });
+  return normalizeFileNodes(res.list);
+}
+
+/** Find the app folder, or make it. Returns its node id. */
+export async function ensureFolder(accountId: Id): Promise<Id> {
+  const props = folderProps();
+  let list: FileNode[] = [];
+  if (queryOmitsDirectories()) {
+    // Query cannot see a directory on these servers, so it would never find the
+    // folder and we would make a fresh one on every save. Ask get for the lot.
+    list = await allNodes(accountId, props);
+  } else {
+    try {
+      const res = await client.chain([
+        ["FileNode/query", { accountId, filter: { isTopLevel: true, nodeType: "directory", name: APP_FOLDER }, limit: 5 }, "q"],
+        ["FileNode/get", { accountId, "#ids": { resultOf: "q", name: "FileNode/query", path: "/ids" }, properties: props }, "g"],
+      ]);
+      list = normalizeFileNodes((res.get("g")?.[0] as unknown as GetResponse<FileNode>).list);
+    } catch {
+      // Filters unsupported: scan everything and pick it out here.
+      const res = await client.chain([
+        ["FileNode/query", { accountId, limit: 1000 }, "q"],
+        ["FileNode/get", { accountId, "#ids": { resultOf: "q", name: "FileNode/query", path: "/ids" }, properties: props }, "g"],
+      ]);
+      list = normalizeFileNodes((res.get("g")?.[0] as unknown as GetResponse<FileNode>).list);
+    }
+  }
+  const existing = list.find(isAppFolder);
+  if (existing) return existing.id;
+  const set = await client.call<SetResponse<FileNode>>("FileNode/set", { accountId, create: { d: directoryCreate(null, APP_FOLDER) } });
+  const err = set.notCreated?.d;
+  if (err) throw new Error(setErrorMessage(err));
+  return set.created!.d!.id;
+}
+
+/** A node's persistent blobId, for servers that do not return one on create. */
+export async function nodeBlobId(accountId: Id, id?: Id): Promise<Id | undefined> {
+  if (!id) return undefined;
+  try {
+    const res = await client.call<GetResponse<FileNode>>("FileNode/get", { accountId, ids: [id], properties: ["id", "blobId"] });
+    return res.list[0]?.blobId ?? undefined;
+  } catch {
+    return undefined;
+  }
+}
+
+/** Find a file by name inside the app folder. */
+export async function findInFolder(accountId: Id, folderId: Id, name: string): Promise<FileNode | undefined> {
+  const props = ["id", "name", "parentId", "blobId", "size", "type", ...(supportsNodeType() ? ["nodeType"] : [])];
+  try {
+    const res = await client.chain([
+      ["FileNode/query", { accountId, filter: { parentId: folderId, name }, limit: 5 }, "q"],
+      ["FileNode/get", { accountId, "#ids": { resultOf: "q", name: "FileNode/query", path: "/ids" }, properties: props }, "g"],
+    ]);
+    const list = normalizeFileNodes((res.get("g")?.[0] as unknown as GetResponse<FileNode>).list);
+    const hit = list.find((n) => n.name === name && n.parentId === folderId);
+    if (hit) return hit;
+  } catch {
+    /* filters unsupported: fall through to the full scan */
+  }
+  const list = await allNodes(accountId, props);
+  return list.find((n) => n.name === name && n.parentId === folderId);
+}

web/src/lib/settingsSync.ts

@@ -0,0 +1,158 @@
+/**
+ * Settings that follow the account rather than the browser.
+ *
+ * Everything used to live in localStorage, which meant no preference travelled
+ * between devices — most painfully the default identity, where the fallback is
+ * whichever address sorts first, so a forgotten setting sends mail from an
+ * address the recipient may not know (issue #54).
+ *
+ * The store is a `settings.json` in the account's own JMAP Files, beside the
+ * signature images that are already kept there. That keeps ihasmail itself
+ * stateless: no volume, no database, nothing to back up separately, and the
+ * settings are covered by whatever backs up the mail store.
+ *
+ * localStorage stays, demoted to a cache: it is what paints the first frame,
+ * and the file overwrites it once it lands. A browser with no cache (a private
+ * window) therefore shows defaults for one frame before the account's real
+ * settings arrive.
+ *
+ * Requires Stalwart 0.16: `FileNode/query` before that cannot see directories
+ * and the rights model differs. On an older server the settings simply stay
+ * local, exactly as they were.
+ */
+import { CAP, client, setErrorMessage } from "@/jmap/client";
+import type { FileNode, Id, SetResponse } from "@/jmap/types";
+import { ensureFolder, findInFolder, nodeBlobId } from "@/lib/appFolder";
+import { fileCreate, supportsNodeType } from "@/lib/filenode";
+import { useSession } from "@/store/session";
+
+const FILE = "settings.json";
+const TYPE = "application/json";
+
+/** How long a change sits before it is written up. */
+const DEBOUNCE_MS = 3000;
+
+let timer: number | null = null;
+let pending: Record<string, unknown> | null = null;
+let inFlight: Promise<void> | null = null;
+/** Nothing is pushed before the first load has settled, or we would race it. */
+let armed = false;
+let listenersBound = false;
+
+export function settingsSyncAvailable(): boolean {
+  return supportsNodeType() && client.hasCapability(CAP.filenode) && Boolean(useSession.getState().accountFor(CAP.filenode));
+}
+
+/**
+ * Read the account's settings file. Returns null when there is nothing to read
+ * — no file yet, no Files, an older server — which leaves the local cache in
+ * charge rather than wiping it.
+ */
+export async function loadRemoteSettings(): Promise<Record<string, unknown> | null> {
+  if (!settingsSyncAvailable()) return null;
+  const accountId = useSession.getState().accountFor(CAP.filenode)!;
+  try {
+    const folderId = await ensureFolder(accountId);
+    const node = await findInFolder(accountId, folderId, FILE);
+    if (!node?.blobId) return null;
+    const text = await client.fetchBlobText(accountId, node.blobId, TYPE);
+    const parsed = JSON.parse(text) as unknown;
+    if (!parsed || typeof parsed !== "object" || Array.isArray(parsed)) return null;
+    return parsed as Record<string, unknown>;
+  } catch {
+    // A settings file we cannot read must not cost anyone their session; the
+    // cached settings are still perfectly good.
+    return null;
+  }
+}
+
+/** Allow pushes. Called once the first load has settled, either way. */
+export function armSettingsSync(): void {
+  armed = true;
+  bindFlushListeners();
+}
+
+/** Stop syncing and drop anything queued (logout). */
+export function stopSettingsSync(): void {
+  armed = false;
+  pending = null;
+  if (timer !== null) {
+    window.clearTimeout(timer);
+    timer = null;
+  }
+}
+
+/**
+ * Queue the synced settings for writing. Called on every change — including
+ * each frame of a splitter drag — so it coalesces: the newest value wins and
+ * one request goes out once the changes stop.
+ */
+export function queueSettingsPush(synced: Record<string, unknown>): void {
+  if (!armed || !settingsSyncAvailable()) return;
+  pending = synced;
+  if (timer !== null) window.clearTimeout(timer);
+  timer = window.setTimeout(() => {
+    timer = null;
+    void flushSettingsPush();
+  }, DEBOUNCE_MS);
+}
+
+/** Write anything queued now, rather than waiting out the debounce. */
+export async function flushSettingsPush(): Promise<void> {
+  if (timer !== null) {
+    window.clearTimeout(timer);
+    timer = null;
+  }
+  if (!pending || !armed) return;
+  const body = pending;
+  pending = null;
+  // Serialise: two overlapping writes could land in either order.
+  inFlight = (inFlight ?? Promise.resolve()).then(() => writeSettings(body)).catch(() => undefined);
+  await inFlight;
+}
+
+async function writeSettings(body: Record<string, unknown>): Promise<void> {
+  if (!settingsSyncAvailable()) return;
+  const accountId = useSession.getState().accountFor(CAP.filenode)!;
+  const json = JSON.stringify(body, null, 2);
+  // Byte length, not character count: a template or a signature with any
+  // non-ASCII in it would otherwise be reported shorter than it is.
+  const blob = new Blob([json], { type: TYPE });
+  const up = await client.upload(accountId, blob, { type: TYPE });
+  const folderId = await ensureFolder(accountId);
+  const existing = await findInFolder(accountId, folderId, FILE);
+  if (existing) {
+    const res = await client.call<SetResponse<FileNode>>("FileNode/set", {
+      accountId,
+      update: { [existing.id]: { blobId: up.blobId, type: TYPE, size: blob.size } },
+    });
+    const err = res.notUpdated?.[existing.id];
+    if (err) throw new Error(setErrorMessage(err));
+    return;
+  }
+  const res = await client.call<SetResponse<FileNode>>("FileNode/set", {
+    accountId,
+    create: { s: fileCreate(folderId, FILE, up.blobId, TYPE) },
+  });
+  const err = res.notCreated?.s;
+  if (err) throw new Error(setErrorMessage(err));
+  // Some servers hand back no blobId on create; ask, so the next read finds it.
+  await nodeBlobId(accountId, (res.created?.s as Partial<FileNode> | undefined)?.id as Id | undefined);
+}
+
+/**
+ * A debounce that outlives the page helps no one, so a tab going away writes
+ * first. `visibilitychange` is the one that fires reliably on mobile; `pagehide`
+ * covers the desktop close.
+ */
+function bindFlushListeners(): void {
+  if (listenersBound || typeof window === "undefined") return;
+  listenersBound = true;
+  const flush = () => {
+    if (pending) void flushSettingsPush();
+  };
+  window.addEventListener("pagehide", flush);
+  document.addEventListener("visibilitychange", () => {
+    if (document.visibilityState === "hidden") flush();
+  });
+}

web/src/lib/signatureImages.ts

@@ -5,47 +5,12 @@
  * turns such references into inline cid: parts when sending.
  */
 import { CAP, client, setErrorMessage } from "@/jmap/client";
-import type { FileNode, GetResponse, QueryResponse, SetResponse } from "@/jmap/types";
+import type { FileNode, QueryResponse, SetResponse } from "@/jmap/types";
-import { directoryCreate, fileCreate, normalizeFileNodes, queryOmitsDirectories, supportsNodeType } from "@/lib/filenode";
+import { fileCreate } from "@/lib/filenode";
+import { ensureFolder, nodeBlobId } from "@/lib/appFolder";
 import { useSession } from "@/store/session";
 import { toast } from "@/ui/toast";
 
-const FOLDER = "ihasmail";
-
-/** Just enough to find the folder, asking for nodeType only where it exists. */
-const folderProps = () => (supportsNodeType() ? ["id", "name", "nodeType", "parentId"] : ["id", "name", "parentId", "blobId", "size", "type"]);
-
-async function ensureFolder(accountId: string): Promise<string> {
-  let list: FileNode[] = [];
-  if (queryOmitsDirectories()) {
-    // Query cannot see a directory on these servers, so it would never find the
-    // folder and we would make a fresh one on every save. Ask get for the lot.
-    const res = await client.call<GetResponse<FileNode>>("FileNode/get", { accountId, ids: null, properties: folderProps() });
-    list = normalizeFileNodes(res.list);
-  } else {
-    try {
-      const res = await client.chain([
-        ["FileNode/query", { accountId, filter: { isTopLevel: true, nodeType: "directory", name: FOLDER }, limit: 5 }, "q"],
-        ["FileNode/get", { accountId, "#ids": { resultOf: "q", name: "FileNode/query", path: "/ids" }, properties: folderProps() }, "g"],
-      ]);
-      list = normalizeFileNodes((res.get("g")?.[0] as unknown as GetResponse<FileNode>).list);
-    } catch {
-      // Filters unsupported: scan everything and pick it out here.
-      const res = await client.chain([
-        ["FileNode/query", { accountId, limit: 1000 }, "q"],
-        ["FileNode/get", { accountId, "#ids": { resultOf: "q", name: "FileNode/query", path: "/ids" }, properties: folderProps() }, "g"],
-      ]);
-      list = normalizeFileNodes((res.get("g")?.[0] as unknown as GetResponse<FileNode>).list);
-    }
-  }
-  const existing = list.find((n) => n.name === FOLDER && n.nodeType === "directory" && !n.parentId);
-  if (existing) return existing.id;
-  const set = await client.call<SetResponse<FileNode>>("FileNode/set", { accountId, create: { d: directoryCreate(null, FOLDER) } });
-  const err = set.notCreated?.d;
-  if (err) throw new Error(setErrorMessage(err));
-  return set.created!.d!.id;
-}
-
 /** Upload an image for use in a signature; returns a same-origin blob URL. */
 export async function uploadSignatureImage(file: File): Promise<string> {
   const accountId = useSession.getState().accountFor(CAP.filenode);
@@ -117,14 +82,4 @@ export async function loadStoredSignature(blobId: string, type = "text/html"): P
   return client.fetchBlobText(accountId, blobId, type);
 }
 
-async function nodeBlobId(accountId: string, id?: string): Promise<string | undefined> {
-  if (!id) return undefined;
-  try {
-    const res = await client.call<GetResponse<FileNode>>("FileNode/get", { accountId, ids: [id], properties: ["id", "blobId"] });
-    return res.list[0]?.blobId ?? undefined;
-  } catch {
-    return undefined;
-  }
-}
-
 export type { QueryResponse };

web/src/store/__tests__/app-folder-hidden.test.ts

@@ -0,0 +1,53 @@
+import { describe, expect, it } from "vitest";
+import { withoutAppFolder } from "../files";
+import type { FileNode } from "@/jmap/types";
+
+/**
+ * The `ihasmail` folder holds signature images and the synced settings file.
+ * They are real nodes in the account — that is what makes them travel — but
+ * they are the client's housekeeping, so Files does not show them.
+ *
+ * Hiding the folder alone is worse than showing it: the tree attaches a node
+ * whose parent is missing to the root, so the signature images would spill out
+ * into the top level looking like the user's own files.
+ */
+
+const node = (id: string, name: string, parentId: string | null, nodeType: "file" | "directory"): FileNode =>
+  ({ id, name, parentId, nodeType, size: null, blobId: null, type: null }) as unknown as FileNode;
+
+describe("hiding the client's folder", () => {
+  it("removes the folder and everything in it", () => {
+    const nodes = [
+      node("f1", "ihasmail", null, "directory"),
+      node("f2", "signature-1.html", "f1", "file"),
+      node("f3", "settings.json", "f1", "file"),
+      node("d1", "Documents", null, "directory"),
+      node("d2", "notes.txt", "d1", "file"),
+    ];
+    expect(withoutAppFolder(nodes).map((n) => n.id)).toEqual(["d1", "d2"]);
+  });
+
+  it("removes nested contents, not just direct children", () => {
+    const nodes = [
+      node("f1", "ihasmail", null, "directory"),
+      node("f2", "images", "f1", "directory"),
+      node("f3", "logo.png", "f2", "file"),
+    ];
+    expect(withoutAppFolder(nodes)).toEqual([]);
+  });
+
+  it("leaves a folder of the same name that the user made inside another", () => {
+    const nodes = [node("d1", "Projects", null, "directory"), node("d2", "ihasmail", "d1", "directory")];
+    expect(withoutAppFolder(nodes).map((n) => n.id)).toEqual(["d1", "d2"]);
+  });
+
+  it("leaves a top-level file that happens to be called ihasmail", () => {
+    const nodes = [node("x1", "ihasmail", null, "file")];
+    expect(withoutAppFolder(nodes).map((n) => n.id)).toEqual(["x1"]);
+  });
+
+  it("returns the list untouched when there is no such folder", () => {
+    const nodes = [node("d1", "Documents", null, "directory")];
+    expect(withoutAppFolder(nodes)).toBe(nodes);
+  });
+});

web/src/store/files.ts

@@ -1,6 +1,7 @@
 import { create } from "zustand";
 import { CAP, JmapMethodError, client, setErrorMessage } from "@/jmap/client";
 import { directoryCreate, fileCreate, fileNodeProps, normalizeFileNodes, queryOmitsDirectories } from "@/lib/filenode";
+import { isAppFolder } from "@/lib/appFolder";
 import type { FileNode, GetResponse, Id, QueryResponse, SetResponse } from "@/jmap/types";
 import { useSession } from "./session";
 
@@ -30,6 +31,31 @@ let filtersSupported = true;
 
 const byName = (a: FileNode, b: FileNode) => (a.nodeType === b.nodeType ? a.name.localeCompare(b.name, undefined, { numeric: true, sensitivity: "base" }) : a.nodeType === "directory" ? -1 : 1);
 
+/**
+ * Drop the client's own `ihasmail` folder, and everything inside it, from a
+ * listing. It holds signature images and the synced settings file — real nodes
+ * in the account, but housekeeping rather than anything the user filed.
+ *
+ * The contents have to go too: the tree attaches a node whose parent is missing
+ * to the root, so hiding the folder alone would spill its files into the top
+ * level, which is worse than showing the folder.
+ */
+export function withoutAppFolder(nodes: FileNode[]): FileNode[] {
+  const hidden = new Set<Id>();
+  for (const n of nodes) if (isAppFolder(n)) hidden.add(n.id);
+  if (!hidden.size) return nodes;
+  for (let grew = true; grew; ) {
+    grew = false;
+    for (const n of nodes) {
+      if (!hidden.has(n.id) && n.parentId && hidden.has(n.parentId)) {
+        hidden.add(n.id);
+        grew = true;
+      }
+    }
+  }
+  return nodes.filter((n) => !hidden.has(n.id));
+}
+
 /** Fetch all nodes (paged, no filter) and rebuild the full children map. */
 async function loadAllNodes(accountId: Id, set: (fn: (s: FilesState) => Partial<FilesState>) => void): Promise<void> {
   const all: FileNode[] = [];
@@ -52,14 +78,17 @@ async function loadAllNodes(accountId: Id, set: (fn: (s: FilesState) => Partial<
       if (!q.ids.length || (q.total != null && position >= q.total)) break;
     }
   }
+  // After the whole collection, not per page: the folder and its contents can
+  // land in different pages, and a half-filtered pass would spill the rest.
+  const visible = withoutAppFolder(all);
   const nodes: Record<Id, FileNode> = {};
   const children: Record<string, Id[]> = { root: [] };
-  for (const n of all) nodes[n.id] = n;
+  for (const n of visible) nodes[n.id] = n;
-  for (const n of all.sort(byName)) {
+  for (const n of visible.sort(byName)) {
     const key = n.parentId && nodes[n.parentId] ? n.parentId : "root";
     (children[key] ??= []).push(n.id);
   }
-  for (const n of all) children[n.id] ??= [];
+  for (const n of visible) children[n.id] ??= [];
   set(() => ({ nodes, children, loading: false, error: null }));
 }
 
@@ -95,10 +124,12 @@ export const useFiles = create<FilesState>((set, get) => ({
       ]);
       const q = res.get("q")?.[0] as unknown as QueryResponse;
       const g = res.get("g")?.[0] as unknown as GetResponse<FileNode>;
+      const listed = withoutAppFolder(normalizeFileNodes(g.list));
+      const keep = new Set(listed.map((n) => n.id));
       set((s) => {
         const nodes = { ...s.nodes };
-        for (const n of normalizeFileNodes(g.list)) nodes[n.id] = n;
+        for (const n of listed) nodes[n.id] = n;
-        return { nodes, children: { ...s.children, [parentId ?? "root"]: q.ids }, loading: false, error: null };
+        return { nodes, children: { ...s.children, [parentId ?? "root"]: q.ids.filter((id) => keep.has(id)) }, loading: false, error: null };
       });
     } catch (err) {
       // Older Stalwart releases don't support parentId / isTopLevel filters: fall back to

web/src/store/session.ts

@@ -3,6 +3,7 @@ import { apiFetch, ApiError, CAP, client } from "@/jmap/client";
 import type { Id, JmapSession } from "@/jmap/types";
 import { push, type PushState } from "@/jmap/push";
 import { setServerLocale } from "@/lib/datetime";
+import { flushSettingsPush, stopSettingsSync } from "@/lib/settingsSync";
 
 export type AuthStatus = "loading" | "anonymous" | "authenticated";
 
@@ -54,6 +55,14 @@ export const useSession = create<SessionState>((set, get) => ({
   async logout() {
     push.stop();
     setServerLocale(null);
+    // Anything still sitting in the debounce is written while the session can
+    // still write it; a setting changed seconds before signing out is not lost.
+    try {
+      await flushSettingsPush();
+    } catch {
+      /* ignore */
+    }
+    stopSettingsSync();
     try {
       await apiFetch("/api/auth/logout", { method: "POST" });
     } catch {
@@ -96,6 +105,7 @@ function applySession(s: JmapSession, set: (p: Partial<SessionState>) => void) {
 
 client.onUnauthenticated(() => {
   push.stop();
+  stopSettingsSync();
   client.session = null;
   useSession.setState({ status: "anonymous", session: null, accountId: null });
 });

web/src/store/settings.ts

@@ -1,6 +1,7 @@
 import { useEffect, useState } from "react";
 import { create } from "zustand";
 import { loadJson, saveJson } from "@/lib/storage";
+import { queueSettingsPush } from "@/lib/settingsSync";
 import { setDateTimePrefs, type DateFormat, type TimeFormat } from "@/lib/datetime";
 
 export type Theme = "system" | "light" | "dark";
@@ -141,12 +142,59 @@ export const DEFAULT_SETTINGS: Settings = {
   defaultIdentityByAccount: {},
 };
 
+/**
+ * Settings that describe *this screen or this browser*, and so stay in
+ * localStorage: a list-pane width picked on a 27" monitor is wrong on a
+ * laptop, and the notification toggles track a permission the browser grants
+ * per-device, so syncing them would claim something untrue elsewhere.
+ *
+ * Everything else follows the account (issue #54). The list is written as the
+ * exceptions rather than the rule so that a setting added later syncs by
+ * default, which is what someone adding one almost always wants.
+ */
+export const DEVICE_KEYS: ReadonlySet<keyof Settings> = new Set<keyof Settings>([
+  "density",
+  "fontSize",
+  "sidebarCollapsed",
+  "desktopNotifications",
+  "notificationSound",
+  "listPaneWidth",
+  "listPaneHeight",
+]);
+
+/** The part of the settings that is written to the account's settings file. */
+export function syncedPart(s: Settings): Record<string, unknown> {
+  const out: Record<string, unknown> = {};
+  for (const key of Object.keys(s) as Array<keyof Settings>) {
+    if (!DEVICE_KEYS.has(key)) out[key] = s[key];
+  }
+  return out;
+}
+
+/**
+ * What of a settings file we are willing to apply: known keys only, and never
+ * a device one — an older ihasmail wrote the whole object up, and that file
+ * should not now drag another machine's pane width across.
+ */
+export function acceptRemote(remote: Record<string, unknown>): Partial<Settings> {
+  const out: Record<string, unknown> = {};
+  for (const [key, value] of Object.entries(remote)) {
+    if (!(key in DEFAULT_SETTINGS)) continue;
+    if (DEVICE_KEYS.has(key as keyof Settings)) continue;
+    if (value === undefined) continue;
+    out[key] = value;
+  }
+  return out as Partial<Settings>;
+}
+
 interface SettingsState {
   settings: Settings;
   update(patch: Partial<Settings>): void;
   reset(): void;
   exportJson(): string;
   importJson(json: string): boolean;
+  /** Apply the account's settings file over the cached ones. */
+  hydrate(remote: Record<string, unknown>): void;
 }
 
 const initialSettings = loadJson<Settings>("settings", DEFAULT_SETTINGS);
@@ -160,12 +208,18 @@ export const useSettings = create<SettingsState>((set, get) => ({
     set({ settings });
     applyTheme(settings);
     applyDateTimePrefs(settings);
+    // Dragging a splitter changes a device key on every frame and must not put
+    // a request in the air; anything else is queued and coalesced.
+    if (Object.keys(patch).some((k) => !DEVICE_KEYS.has(k as keyof Settings))) {
+      queueSettingsPush(syncedPart(settings));
+    }
   },
   reset() {
     saveJson("settings", DEFAULT_SETTINGS);
     set({ settings: DEFAULT_SETTINGS });
     applyTheme(DEFAULT_SETTINGS);
     applyDateTimePrefs(DEFAULT_SETTINGS);
+    queueSettingsPush(syncedPart(DEFAULT_SETTINGS));
   },
   exportJson() {
     return JSON.stringify(get().settings, null, 2);
@@ -179,6 +233,14 @@ export const useSettings = create<SettingsState>((set, get) => ({
       return false;
     }
   },
+  hydrate(remote) {
+    const settings = { ...get().settings, ...acceptRemote(remote) };
+    // Cache it, so the next first frame on this browser is already right.
+    saveJson("settings", settings);
+    set({ settings });
+    applyTheme(settings);
+    applyDateTimePrefs(settings);
+  },
 }));
 
 function applyDateTimePrefs(s: Settings): void {