diff --git a/client/ui/CLAUDE.md b/client/ui/CLAUDE.md
index f562d1206..62963fa87 100644
--- a/client/ui/CLAUDE.md
+++ b/client/ui/CLAUDE.md
@@ -37,7 +37,7 @@ All services live in `services/` and assume a build tag `!android && !ios && !fr
 | `Update` | `update.go` | `GetState` / `Trigger` (enforced installer) / `GetInstallerResult` / `Quit`. The install-progress UI lives in its own auxiliary window (`/#/install-progress`), opened by `WindowManager.OpenInstallProgress` — the daemon goes unreachable mid-install so it can't be inside the main window. |
 | `WindowManager` | `windowmanager.go` | `OpenSettings(tab)` / `OpenBrowserLogin(uri)` / `CloseBrowserLogin` / `OpenSessionExpired` / `OpenSessionAboutToExpire(seconds)` / `OpenInstallProgress(version)` / `CloseInstallProgress`. `OpenSettings("")` opens the General tab; pass a tab id (e.g. `"profiles"`) to deep-link, encoded as `?tab=…` in the start URL. `OpenInstallProgress` is `AlwaysOnTop` and hides every other visible window for the duration of the install (restored on close). Auxiliary windows are created on first open and **destroyed** on close (Wails-recommended singleton pattern; prevents the macOS dock-reopen from resurrecting hidden windows). |
 | `I18n` | `i18n.go` | Thin facade over `i18n.Bundle`. `Languages()` returns the shipped locales (`_index.json`); `Bundle(code)` returns the full key→text map for one language so the React layer can drive its own translation library. |
-| `Preferences` | `preferences.go` | Thin facade over `preferences.Store`. `Get()` returns `{language}`; `SetLanguage(code)` validates against `i18n.Bundle.HasLanguage`, persists, and broadcasts `netbird:preferences:changed`. |
+| `Preferences` | `preferences.go` | Thin facade over `preferences.Store`. `Get()` returns `{language, viewMode}`; `SetLanguage(code)` validates against `i18n.Bundle.HasLanguage` and persists; `SetViewMode(mode)` validates against the known set (`default`/`advanced`) and persists. Both broadcast `netbird:preferences:changed`. `main.go` reads `viewMode` from the store to size the main window at startup. |
 
 `DaemonConn` is defined in `services/conn.go`; `ptrStr` (string-to-*string helper for proto pointer fields) lives there too.
 
diff --git a/client/ui/frontend/CLAUDE.md b/client/ui/frontend/CLAUDE.md
index 5025e43d0..c2a755e9a 100644
--- a/client/ui/frontend/CLAUDE.md
+++ b/client/ui/frontend/CLAUDE.md
@@ -76,7 +76,7 @@ State that crosses screens / windows lives in context. Each provider is mounted
 
 ### Default/Advanced view + no client-side persistence
 
-The Header's "more" dropdown owns a `viewMode: "default" | "advanced"` `useState` and calls `Window.SetSize(width, 640)` directly on change. Sizes live in `VIEW_SIZE` at the top of `Header.tsx`: Default = 380×640, Advanced = 900×640 — the 640 height matches the Settings window so chrome height is consistent across surfaces. Every app launch starts in Default (the Go-side main window is created 380×640 in `main.go`). **No `localStorage` / `sessionStorage` / cookies anywhere in the frontend** — persistence is the Go side's job (settings → `SetConfig`, language → `Preferences.SetLanguage`).
+The `ViewModeProvider` (`src/lib/viewMode.tsx`, mounted in `AppLayout`) owns a `viewMode: "default" | "advanced"` state and is consumed by `Header.tsx`'s "more" dropdown via `useViewMode()`. `setViewMode` does three things: updates state, calls `Window.SetSize(width, 640)`, and persists via `Preferences.SetViewMode`. Sizes live in `VIEW_SIZE` at the top of `viewMode.tsx`: Default = 380×640, Advanced = 900×640 — the 640 height matches the Settings window so chrome height is consistent across surfaces. The view is persisted user-side (see Go-side `preferences.Store`): `main.go` opens the main window at the saved width so the user never sees a 380→900 flash on launch, and the provider hydrates its React state from `Preferences.Get()` in a mount effect (no resize triggered there — Go already sized it). **No `localStorage` / `sessionStorage` / cookies anywhere in the frontend** — persistence is the Go side's job (settings → `SetConfig`, language → `Preferences.SetLanguage`, view mode → `Preferences.SetViewMode`).
 
 ## Localisation (i18n)
 
diff --git a/client/ui/frontend/src/lib/viewMode.tsx b/client/ui/frontend/src/lib/viewMode.tsx
index 988f8f116..c80aeae43 100644
--- a/client/ui/frontend/src/lib/viewMode.tsx
+++ b/client/ui/frontend/src/lib/viewMode.tsx
@@ -1,5 +1,7 @@
-import { createContext, useCallback, useContext, useState, type ReactNode } from "react";
+import { createContext, useCallback, useContext, useEffect, useState, type ReactNode } from "react";
 import { Window } from "@wailsio/runtime";
+import { Preferences } from "@bindings/services";
+import { ViewMode as ViewModePref } from "@bindings/preferences/models.js";
 
 export type ViewMode = "default" | "advanced";
 
@@ -20,12 +22,33 @@ const ViewModeContext = createContext<ViewModeContextValue | null>(null);
 
 export const ViewModeProvider = ({ children }: { children: ReactNode }) => {
     const [viewMode, setMode] = useState<ViewMode>("default");
+
+    // Hydrate from the persisted preference. The Go side has already sized
+    // the main window to match (see main.go), so this only catches the
+    // React state and dropdown checkmark up — no resize is triggered here.
+    useEffect(() => {
+        let cancelled = false;
+        void Preferences.Get()
+            .then((prefs) => {
+                if (cancelled) return;
+                const saved = prefs?.viewMode as ViewMode | undefined;
+                if (saved === "default" || saved === "advanced") {
+                    setMode(saved);
+                }
+            })
+            .catch(() => {});
+        return () => {
+            cancelled = true;
+        };
+    }, []);
+
     const setViewMode = useCallback(
         (mode: ViewMode) => {
             setMode((prev) => {
                 if (prev === mode) return prev;
                 const { width, height } = VIEW_SIZE[mode];
                 void Window.SetSize(width, height).catch(() => {});
+                void Preferences.SetViewMode(mode as unknown as ViewModePref).catch(() => {});
                 return mode;
             });
         },
diff --git a/client/ui/main.go b/client/ui/main.go
index 27b4cfc9b..80e5f206c 100644
--- a/client/ui/main.go
+++ b/client/ui/main.go
@@ -178,10 +178,17 @@ func main() {
 	app.RegisterService(application.NewService(services.NewI18n(bundle)))
 	app.RegisterService(application.NewService(services.NewPreferences(prefStore)))
 
+	// Open the main window at the width matching the user's last view
+	// choice so an Advanced-mode user doesn't see the window pop from 380px
+	// to 900px on every launch. Height is the same in both modes.
+	initialWidth := 380
+	if prefStore.Get().ViewMode == preferences.ViewModeAdvanced {
+		initialWidth = 900
+	}
 	window := app.Window.NewWithOptions(application.WebviewWindowOptions{
 		Name:                "main",
 		Title:               "NetBird",
-		Width:               380,
+		Width:               initialWidth,
 		Height:              640,
 		Hidden:              true,
 		BackgroundColour:    application.NewRGB(24, 26, 29),