Give the complete URL for the office Chat system that you use here. Once you have given this setting, then you can invoke the chat right from within TAD itself. This is a very simple way to communicate between your team members, especially when you are all collaborating together; as the chat window will pop up within TAD itself.

There is a menu item under the Help menu which opens this Office chat website. It would try to open the chat inside the internal browser given in TAD. Some modern chat systems unfortunately do not open in such embedded browsers. In such a case, you will need to use an external browser.