How can I prevent Backspace from navigating back in javascript?

Question

This works in IE, but I cannot get it to work in Opera or Firefox. I want to prevent Backspace from navigating away if and only if the current focus is the SELECT dropdown.

Answer 1

That's trickier than I would have thought. Depending on the reason you are preventing the user from backspacing away from the page, something like this might work for you: