In some contexts, it can be very useful to read directly the prior n-th item from the current ChromeVox range.

For example, within a Gmail chat, it might be useful to read the last message, the second to last message, etc while focus is within the chat entry text field.

Possible keys:
- alt-1: ChromeVox outputs the previous object, but does not set its range there
- alt-2: same as above, except for the previous previous object
- double pressing would move to the previous of that position
prev

It might be useful to extend this support somehow, the Gmail message view.