Hello Kirk,
when you have a contact sheet open with just few photos (just enough to fit into one "page" of contact sheet window, without scrolling) and I press END key, the photos disappear until I scroll back up with HOME or mouse scroll. The photos also appear in the middle of the window upon moving the mouse cursor. This has been going for a long time, only in windows with few enough photos to fit on one page. See attached screenshots (pixellated on purpose), first is normal, second is after pressing END, third is after moving mouse cursor.
It is rare enough that I work with just that few photos in one folder, so it's not much of a problem (and it's only a display bug), just posting it here for your consideration.
OS X 10.12.6, PM 18895. No Windows computer here at the moment to test there.
