geckoWebBrowser1.DomDocument.GetElementById("IdHere").SetAttribute("value", textBox1.Text);
geckoWebBrowser1.DomDocument.GetElementById("IdHere").SetAttribute("value", textBox2.Text);
GeckoHtmlElement SwagSubmitField =
(GeckoHtmlElement)geckoWebBrowser1.DomDocument.GetElementById("loginBtn");
SwagSubmitField.Click();
Ticker.Time(2);