Player Version#: 1.9.0
The new Plex Player 1.9.0 for MacOS appears to not be able to open a window for a non-admin account.
Happens under MacOS 10.15.4. The previous versions did not have this problem. When running under the admin/install account all works correctly (opens a window, connects to server, etc.). When run under a non-admin account the app starts (slowly!), can be quit, but does not display a window.
Reboot does not fix. The app requests no OS access privileges.