JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
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.
Unfortunately, you cannot currently configure the lightbox embed code to automatically close/disappear after submission. As a workaround, you can try to set the Thank You page to a URL so whenever the form is submitted it will redirect to a different page. If the workaround will not work for you, we can escalate a feature request for you to our development team so they can take this feature into consideration. Please confirm. But I cannot guarantee that this feature will be implemented immediately.
Do let us know if you need further assistance.