Never show the main window on a daemon launch

src/UniGetUI.Avalonia/App.axaml.cs

@@ -149,19 +149,6 @@ private static void StartMainWindow(IClassicDesktopStyleApplicationLifetime desk
             };
         }
 
-        if (CoreData.WasDaemon)
-        {
-            // Start silently: hide the window on first open only.
-            // Opened fires on every Show() in Avalonia, so we must unsubscribe
-            // immediately or every ShowFromTray() call would hide the window again.
-            void HideOnce(object? s, EventArgs e)
-            {
-                mainWindow.Opened -= HideOnce;
-                mainWindow.Hide();
-            }
-            mainWindow.Opened += HideOnce;
-        }
-
         if (splash is not null)
         {
             var splashRef = splash;
@@ -173,9 +160,10 @@ void CloseSplashOnce(object? s, EventArgs e)
             mainWindow.Opened += CloseSplashOnce;
         }
 
-        // Framework auto-show already passed (we deferred via Dispatcher.Post),
-        // so we have to open the window ourselves.
-        mainWindow.Show();
+        // Framework auto-show already passed (we deferred via Dispatcher.Post), so we have to
+        // open the window ourselves. Daemon mode never shows it at all.
+        if (!CoreData.WasDaemon)
+            mainWindow.Show();
 
         _ = StartupAsync(mainWindow);
     }
@@ -194,12 +182,7 @@ private static async Task StartupAsync(MainWindow mainWindow)
                 // ShowDialog tries to attach to it as owner.
                 await Task.Yield();
 
-                // ShowDialog requires a visible owner. In daemon mode the main window
-                // is hidden, so temporarily show it and re-hide after the dialog closes.
-                bool reshide = CoreData.WasDaemon;
-                if (reshide) mainWindow.Show();
-                await new CrashReportWindow(report).ShowDialog(mainWindow);
-                if (reshide) mainWindow.Hide();
+                await mainWindow.ShowDialogAndRestoreVisibilityAsync(new CrashReportWindow(report));
             }
             catch { /* must not prevent normal startup */ }
         }

src/UniGetUI.Avalonia/Infrastructure/AvaloniaBootstrapper.cs

@@ -91,14 +91,14 @@ await Dispatcher.UIThread.InvokeAsync(
     private static async Task ShowIntegrityViolationDialogAsync()
     {
         if (MainWindow.Instance is not { } owner) return;
-        await new IntegrityViolationDialog().ShowDialog(owner);
+        await owner.ShowDialogAndRestoreVisibilityAsync(new IntegrityViolationDialog());
     }
 
     private static async Task ShowMissingDependencyDialogAsync(
         ManagerDependency dep, int current, int total)
     {
         if (MainWindow.Instance is not { } owner) return;
-        await new MissingDependencyDialog(dep, current, total).ShowDialog(owner);
+        await owner.ShowDialogAndRestoreVisibilityAsync(new MissingDependencyDialog(dep, current, total));
     }
 
     private static Task InitializeSharedServicesAsync()

src/UniGetUI.Avalonia/Views/MainWindow.axaml.cs

@@ -829,6 +829,11 @@ private void SaveGeometryNow()
     {
         try
         {
+            // Width/Height stay NaN until the window has been laid out, which never happens on a
+            // daemon launch the user has not opened yet. Saving then would persist a 0x0 size.
+            if (double.IsNaN(Width) || double.IsNaN(Height))
+                return;
+
             int state = WindowState == WindowState.Maximized ? 1 : 0;
             string geometry = $"v2,{Position.X},{Position.Y},{(int)Width},{(int)Height},{state}";
             Settings.SetValue(Settings.K.WindowGeometry, geometry);
@@ -1556,6 +1561,25 @@ public async Task ShowManageIgnoredUpdatesAsync()
         await ShowImmersiveDialogAsync(dialog);
     }
 
+    // Immersive dialogs are hosted inside this window, so they are unreachable — and never complete —
+    // while it is off screen (daemon launch). Bring it up for the dialog and put it back after.
+    public async Task ShowDialogAndRestoreVisibilityAsync(ImmersiveDialog dialog)
+    {
+        bool reshide = !IsVisible;
+        if (reshide)
+            Show();
+
+        try
+        {
+            await dialog.ShowDialog(this);
+        }
+        finally
+        {
+            if (reshide)
+                Hide();
+        }
+    }
+
     public async Task ShowImmersiveDialogAsync(ImmersiveDialog dialog)
     {
         var completion = new TaskCompletionSource(TaskCreationOptions.RunContinuationsAsynchronously);