You right click on file(s) at Staged area and from context menu you choose "Stop tracking". Popup/Modal confirmation window appears with "Ok", "Cancel" and "Close" buttons.
1. When you click "Ok" nothing happens. Files in Staged and Unstaged areas are unchanged.
2. When you click "Cancel" file(s) moves to Unstaged area.
3. When you click "Close" file(s) moves to Unstaged area.

I consider functionality of :
"Ok" button (1.) should be to move files to Unstaged area.
"Cancel" button (2.) and "Close" button (3.) should be do nothing, cancel or close selection.

"Ok" has swapped functionality with "Cancel" and "Close".