Hello,
With 8.2.3, the Landing Page Designer allows me to create a Landing Page with a form, export in HTML, publish it on my domain name.
The page and forms works well and a NEW submitted form record & contact are created in the CRM.
After submitting the form, the message displayed on the screen is as followed:

Where and How can we customize the message OR redirect to a Thank YOU page ?
PS : the version field when creating this POST has only 8.0 as an option.