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:
  ____    ____  ____    ____   ____
 / __ \  / __/ / __ \  / __/  /  _/
/ /_/ / / _/  / /_/ / _\ \   _/ /  
\___\_\/___/  \____/ /___/  /___/