CefSharp 获取 C# 页面源代码

大家好，我想获取页面的源代码，但是 CeFSharp 在输出时为我打开了一个记事本，带有 html ... 告诉我如何修复它，以便仅在变量中输入数据。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using CefSharp;
using CefSharp.WinForms;
namespace Rate_Scanner
{
    public partial class FonbetForm : Form
    {
        ChromiumWebBrowser chrome;
        public FonbetForm()
        {
            InitializeComponent();
            InitializeChromeBrowser();
        }
        private void InitializeChromeBrowser()
        {
            CefSettings cefSettings = new CefSettings();
            Cef.Initialize(cefSettings);
            chrome = new ChromiumWebBrowser("https://www.youtube.com/watch?v=UOyYR72R7Ik");
            chrome.Dock = DockStyle.Fill;
            this.Controls.Add(chrome);
        }
        private string FonbetPage()
        {
            chrome.ViewSource();
            var html = "";
            chrome.GetSourceAsync().ContinueWith(taskHtml =>
            {
                 html = taskHtml.Result;
            });
            return html;
        }
        private void button1_Click(object sender, EventArgs e)
        {
            FonbetPage();
        }
    }
}