Style guide: combo box

Combo box comments:

1. Grammar error here: "As focus moves inside the dropdown list, the edit 
field is not updated until. "  ... until what?
2. Should F4 also be supported? Some users know that instead of Alt+down 
to open it
3. Tab key is listed twice and says different things
4. Space is not usually supported for selection in a combo box, because 
combo boxes are not generally used for multiple selection (because they 
can usually only show 1 result). Is this an intentional break from 
tradition? If so, perhaps it should describe this and say how the multiple 
selection is displayed in the single field.
5. For up and down arrow, it does not describe the 2 different behaviors 
depending on whether the combo is currently open or closed
6. We are missing a description for listbox. I suggest combo box should 
say something like "In addition, support the behavior of a single select 
listbox when the combo is open"
7. Do they cycle? In other words if you arrow past the beginning or end of 
the list does it stay there or wrap around? This could be part of the 
definition of listbox and then borrowed by pointing to that.
8. As mentioned earlier, incremental find as you type is not mentioned for 
the listbox. This could also be part of the definition of listbox and then 
borrowed by pointing to that.
9. Pageup/pagedown/home/end are missing from the defintion. These could 
also be part of the definition of listbox and then borrowed by pointing to 
that.

- Aaron