final HtmlPage confirmPage = button.click();
form = confirmPage.getFormByName("loginform");
button = (HtmlElement) confirmPage.createElement("button");
button.setAttribute("type", "submit");
form.appendChild(button);
// button = form.getButtonByName("wp-submit");
final HtmlPage callbackPage = button.click();
final String callbackUrl = callbackPage.getUrl().toString();
logger.debug("callbackUrl : {}", callbackUrl);