Unless I'm missing something that will not fix the arrow navigation. It puts the cell in edit mode (highlighted text etc.), which effectively prevents you from (immediately) navigating with the arrow keys.
The goal at hand is to focus on the listbox so that the user can immediately start navigation (without discovering that the navigation starts off from a different line than the currently selected one).
Bringing the cell into edit mode would a) require the user to press Enter before being able to start navigation, and b) introduces edit mode even in cases where editing is not supposed to be allowed (and hence even visible as a concept for that control).
