I want to integrate Marketo form with my existing website on yii framework. My code works on all the browsers except Firefox.

Excerpt from my code:

    $('#button').click(function () {
    var formData = {
        'Email': $('#UserInfo_email').val(),
        'FirstName': $('#UserInfo_first_name').val(),
        'LastName': $('#UserInfo_last_name').val(),
        };
    MktoForms2.loadForm('//app-ab23.marketo.com', mcId, formId, function (form) {
        var myForm = MktoForms2.allForms()[0];
        myForm.addHiddenFields(formData);
        myForm.onSuccess(function (values, followUpUrl) {
            return false;
        });
        myForm.submit();
    });
});

I get error on Firefox only with message

  
Loading failed for the <script> with source “http://app-ab23.marketo.com/index.php/form/getForm?munchkinId=1111&form=1111&url=http%3A%2F%2Fblox.dev%2Fwizard%2Fmap&callback=jQuery110207175825035737486_1503656391790&_=1503656391791”.

other browsers do the job correctly

note: munchkinId and formId are changed for posting here.