protected override async void OnStartup(object sender, StartupEventArgs e) { var startupTasks = GetAllInstances(typeof(StartupTask)) .Cast <ExportedDelegate>() .Select(exportedDelegate => (StartupTask)exportedDelegate.CreateDelegate(typeof(StartupTask))); startupTasks.Apply(s => s()); base.OnStartup(sender, e); await NatHelper.DiscoverAsync(); ThemeManager.AddAppTheme("CobaltLight", new Uri("pack://application:,,,/Themes/CobaltLight.xaml")); ThemeManager.AddAppTheme("CobaltDark", new Uri("pack://application:,,,/Themes/CobaltDark.xaml")); ThemeManager.ChangeAppStyle(Application.Current, ThemeManager.Accents.First(a => a.Name == "Blue"), ThemeManager.GetAppTheme("CobaltLight")); }