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