block contacts who opted out of all email from form
It would be really useful if you had the option to block contacts from submitting your forms when they already opted out of all email.
Currently what happens is that a message pops up saying "it looks like you already opted out of all email" but they can still submit the form.
In some cases this can be problematic, because some customers miss this message and are then wondering why they are not receiving marketing emails even though the submitted a form.
In those cases it would be a great addition to have the option to block contacts who opted out of all email from submitting the form in the first place.