App.xaml.cs

using System;
using System.Windows;

namespace ColorCodeWebViewApp
{
    public partial class App : Application
    {
        protected override void OnStartup(StartupEventArgs e)
        {
            AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
            DispatcherUnhandledException += new System.Windows.Threading.DispatcherUnhandledExceptionEventHandler(App_DispatcherUnhandledException);

            base.OnStartup(e);
        }

        void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
        {
            MessageBox.Show((e.ExceptionObject as Exception).Message, "Unhandled Domain Exception");
        }

        void App_DispatcherUnhandledException(object sender, System.Windows.Threading.DispatcherUnhandledExceptionEventArgs e)
        {
            MessageBox.Show(e.Exception.Message, "Unhandled Dispatcher Exception");
            e.Handled = true;
        }
    }
}