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:
     __   _  __ ______  _____ ______
 __ / /  / |/ //_  __/ / ___//_  __/
/ // /  /    /  / /   / /__   / /   
\___/  /_/|_/  /_/    \___/  /_/