Force Plex Apps / Devices to connect via "Custom certificate domain" / "Custom server access URLs" instead of the Public IP of the Server

[SwiftPanda16]

Plex reverts to *.plexdirect even though a custom domain is connected

Disable remote access and it will stop using the *.plex.direct address. As long as your domain is filled in to the “Custom Server access URLs” setting, everything will use that address, including remote access.