What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
Thank you for contacting us.
When you get the embed code in Lightbox format you "X" button is not present in the form but you are referring to the form being closed when the clicking outside the pop up box and you want to disable this you can replace this http://cdn.jotfor.ms/static/feedback2.js?3.2.923 in your embed code to this http://cdn.jotfor.ms/static/feedback.js?3.2.923
That uses the old version of Jotform's js. If this is not what you are trying to achieve please explain further so we can give and provide appropriate answer to your question.