Tab and arrow keys in the Lightbox component

[Mark Norton]

Anastasia Cheetham wrote:

> But the tab key currently doesn't move focus within the major areas 
> inside the tool e.g. in the case of the Gallery, between the 
> Collections list on the left and the photos on the right. We will need 
> to address this somehow.

Is this a browser function, or a matter of adding appropriate 
Javascript?  I'm not sure I'd expect the focus to step down into an 
iFrame from the browser window, unless the user selects an object in the 
frame.

- Mark Norton