Open a custom terms of use page before starting the chat

Content

Hello Everyone,

My business team wants users to accept terms of use content for the chat before a chat session should start. I was thinking of throwing a custom content modal window before starting chat Session.

Is there a way to achieve this ?

I was looking at this example, but not sure where to modify the code ? Should I create another widget ?:

http://jsfiddle.net/ma4Ld3v7/9/