var newCaptchaInput = document.createElement('input');
newCaptchaInput.setAttribute('type', 'hidden');
newCaptchaInput.setAttribute('id', 'wlCaptchaToken');
newCaptchaInput.setAttribute('name', 'wlCaptchaToken');
document.getElementById('nl_register_form').appendChild(newCaptchaInput);
newCaptchaInput = null;
var xhrForm = new XMLHttpRequest();
xhrForm.onload = function () {
        document.getElementById("wlCaptchaToken").value = xhrForm.response;
};
xhrForm.open("GET", "https://booking.seevilla.at/websLINE-ABM/WlCaptcha/GetToken");
xhrForm.setRequestHeader("Cache-Control", "no-cache");
xhrForm.send();