This is not a Bug report but a "likely confusion" report.
When exiting the face manager one gets:
save changes.jpg
The big text "Save changes" is contrary to the small text "Do you really want to exit without saving...."
The YES button refers to this second text.
I suggest changing "Save Changes" to "Discard Changes"
That's not a bug. I'll move this into the better suited board (https://www.photools.com/community/index.php/board,14.0.html).
I've changed the headline to the dialog to Faces Modified!, which works better.