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