Here's are the modification to the MinimalExample, never really worked with github, so this is the best i can do for now, sry :/

MainWindow.xaml.cs

using System.Windows;

namespace CefSharp.MinimalExample.Wpf
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            Browser.RequestHandler = new AuthHandler();
        }
    }

    public class AuthHandler : IRequestHandler
    {

        public bool OnBeforeBrowse(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, bool isRedirect)
        {
            return false;
        }

        public bool OnOpenUrlFromTab(IWebBrowser browserControl, IBrowser browser, IFrame frame, string targetUrl, WindowOpenDisposition targetDisposition, bool userGesture)
        {
            return false;
        }

        public bool OnCertificateError(IWebBrowser browserControl, IBrowser browser, CefErrorCode errorCode, string requestUrl, ISslInfo sslInfo, IRequestCallback callback)
        {
            return false;
        }

        public void OnPluginCrashed(IWebBrowser browserControl, IBrowser browser, string pluginPath)
        {
            return;
        }

        public CefReturnValue OnBeforeResourceLoad(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
        {
            return CefReturnValue.Continue;
        }

        public bool GetAuthCredentials(IWebBrowser browserControl, IBrowser browser, IFrame frame, bool isProxy, string host, int port, string realm, string scheme, IAuthCallback callback)
        {
            callback.Continue("***", "***");
            return true;
        }

        public void OnRenderProcessTerminated(IWebBrowser browserControl, IBrowser browser, CefTerminationStatus status)
        {
            return;
        }

        public bool OnQuotaRequest(IWebBrowser browserControl, IBrowser browser, string originUrl, long newSize, IRequestCallback callback)
        {
            return false;
        }

        public void OnResourceRedirect(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, ref string newUrl)
        {
            return;
        }

        public bool OnProtocolExecution(IWebBrowser browserControl, IBrowser browser, string url)
        {
            return false;
        }

        public void OnRenderViewReady(IWebBrowser browserControl, IBrowser browser)
        {
            return;
        }

        public bool OnResourceResponse(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, IResponse response)
        {
            return false;
        }

        public IResponseFilter GetResourceResponseFilter(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, IResponse response)
        {
            return null;
        }

        public void OnResourceLoadComplete(IWebBrowser browserControl, IBrowser browser, IFrame frame, IRequest request, IResponse response, UrlRequestStatus status, long receivedContentLength)
        {
            return;
        }
    }
}