public static void Main()
var html = @"https://www.TechnologyCrowds.com/";
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;
HtmlWeb web = new HtmlWeb();
var htmlDoc = web.Load(html);
var favicon = (dynamic)null;
var el = htmlDoc.DocumentNode.SelectSingleNode("/html/head/link[@rel='icon' and @href]");
favicon = el.Attributes["href"].Value;
Console.WriteLine(Convert.ToString(favicon));