EnvyUpdate/EnvyUpdate/App.xaml.cs

using Microsoft.Toolkit.Uwp.Notifications;
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;
using Windows.Foundation.Collections;
using Wpf.Ui.Markup;

namespace EnvyUpdate
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        protected override void OnStartup(StartupEventArgs e)
        {
            // Listen to notification activation
            ToastNotificationManagerCompat.OnActivated += ToastNotificationManagerCompat_OnActivated;
        }

        private void ToastNotificationManagerCompat_OnActivated(ToastNotificationActivatedEventArgsCompat e)
        {
            // Need to dispatch to UI thread if performing UI operations
            Application.Current.Dispatcher.Invoke(delegate
            {
                Util.ShowMain();
            });
        }
    }
}