You double set CefSettings. You must first configure. Configure is once in project and it should be before first call InitializeComponent() in your application.
public debug()
{
Configure();
InitializeComponent();
CreateNewBrowser();
}
public void Configure()
{
CefSettings cfsettings = new CefSettings();
cfsettings.CefCommandLineArgs.Add("proxy-server", "200.29.191.149:3128");
cfsettings.UserAgent = "My/Custom/User-Agent-AndStuff";
Cef.Initialize(cfsettings);
}
public void CreateNewBrowser()
{
browser = new ChromiumWebBrowser("https://whatismyipaddress.com/");
this.Controls.Add(browser);
browser.Dock = DockStyle.Fill;
}