The ability to use up and down arrow keys on a combo box menu

[zrksyd]

When a combo box widget is active, the use of up and down arrows to go through each option would be convenient.

[ScanMountGoat]

It should be relatively simple to check for arrow keys from the response. The problem is knowing what the next and previous elements are. Not all the comboboxes work on lists, so there isn't always an easy way to convert the selected item to a selected index. I'm not sure how involved the refactoring will need to be to make this work.