HTMLDocument Confirm Method
Displays a confirmation box and waits for a response.
R←I Confirm [T [M [B]]]
I is an HTMLDocument instance. T is the title, a character vector. It defaults to "Confirm". M is the message, character vector or list. It defaults to "Continue?" B is a list of button captions. It defaults to 'Yes' 'No'. R is the button caption of the selected option, or an empty vector if Escape is pressed.