The mouseMove event is designed to move around the canvas itself, but I cannot detect when the mouse leaves the canvas.
Is it possible to detect when the mouse moves from the canvas?
Have you tried mouseout ?
mouseout
element.addEventListener ("mouseout", myFunction, false);
All mouse events that apply to html elements are listed here: http://www.w3schools.com/tags/ref_eventattributes.asp (scroll down to Mouse Events).