Block show the default VtigerCRM Confirmation box to let them decide something.
You could configure the text, the User see.
This configuration result into this in Frontend:

Enter your comment. Wiki syntax is allowed:
   __   _      __   ___   ____    ___ 
  / /  | | /| / /  / _ \ / __ \  / _ \
 / /__ | |/ |/ /  / , _// /_/ / / ___/
/____/ |__/|__/  /_/|_| \___\_\/_/