Ability to close a support session with a keystroke

Partner would like the ability to close a support session without having to take control of the mouse.

User Story:
There are instances when a partner needs to observe a customer in a session without disturbing them. When the product's focus is on the SC host client, any keystroke or mouse movement, of course, is sent directly to the customer. So in order to leave the session you have to "fight" the customer for control of the mouse to hit the exit button.

A keyboard shortcut comments would work well.