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:
   __ __  ____  _____   __ __  ____ 
  / //_/ /_  / / ___/  / // / / __ \
 / ,<     / /_/ /__   / _  / / /_/ /
/_/|_|   /___/\___/  /_//_/  \____/