This is not Mac specific. My PMS was running on Windows for a couple of years. Now I switched to Centos7 and the bug/feature still exists.
When a friend is watching a show or a movie it (sometimes) it gets marked as viewed (in the XML viewCount and lastViewed is set).
I'd rather not like this to happen in my library.
I know that this "feature" is disabled when the PMS owner does not have a PlexPass (like me). Then the watched flag can only be set by the owner and not by any shared friend.
Is there a way to forbid PMS this? Couldn't find anything under the friends sharing options or the library settings.
Thank you very much
CCarpo