Hello and thank you for reaching out to The Community. We do apologize, but at this time we do not have the ability to edit the Thank You message from our pop up sign-up forms. This is however a feature request, so you are not the only one looking for this addition to our platform. I will be submitting this feedback to our Product Team to ensure they know that our customers are still looking for this change. If there is anything else we can assist with please do not hesitate to ask!