Hey @trekkie,
Although I am not proficient with plex, having used the container over the weekend and knowing a bit about containers, I think it’s not related to Netdata.
Due to the tech, I am almost certain that it should just “play”, since the netdata environment doesn’t change from container engine to container engine.
That being said, an error line in the code you supplied mentions that it was not possible to read proc. Can you verify that the docker runtime that you use allows this volume mount? - /proc:/host/proc:ro
For example, in balena, although it’s docker-container, in order to give access to proc, you have to pass a label.