The behavior is reproducible if you have selected item(s) at the beginning of the list and one of them is focused. In this case, if you scroll down, so the selected item is out of view, pressing `Shift` or `Ctrl` scrolls to the focused selected item at the top preventing you from clicking on the last item.

The same issue can be reproduced in reverse - if you select an item at the bottom and scroll to the top so the selection is not in the view. In this case, pressing `Shift` or `Ctrl` will force scroll down to the focused selected item.

The issue is reproducible in both selection modes.

When the ListBox is focused for the first time via the keyboard, it should focus the first selected item. Currently it focuses the first item, regardless of selection.