Pour info, pour MAJ manuellement : Manually updating Plex Media Server on MyCloud NAS
Par contre effectivement, l’acces au dossier systeme de plex semble impossible
Manually Installing Plugins
When running on the My Cloud Home, the Plex Media Server data directory is not user-accessible. One consequence of this is that it is not possible to manually install plugins on the device, sorry.
https://support.plex.tv/articles/115003310834-western-digital-my-cloud-home/