IPad Pro - Where's the button to initiate a Chat when doing a Remote Desktop

I just installed Team Viewer Remote Control on my iPad Pro 12".

When connected to another computer, there are icons in the bottom right hand part of the screen that allow me to control some Team Viewer functions.

I cannot figure out however how to open a Chat Window so I can't chat with the person on the other side.

What am I missing?

Where's the button so I can send a text chat message?