I found the thread on the changes made to the plex install from version 1.15.4.994 and beyond: Plex Media Server security changes for Synology users
Some feedback:
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I think the server could check if there’s been an upgrade recently “jumping” the versions boundary and show some help text.
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Even after restarting, I can see the Plex user listed as part of the “administrators” group, so I’m not sure the change has been “effective” (?) (And also, if Plex is still an admin, why was I getting the errors??)
