Setting default player - TV isn't a choice



I have the Alexa skill installed and it can open Plex. However, when I try to set the default player, it only lists Chrome web and Firefox web. My Samsung smart TV with the Plex app installed and running isn't listed as a choice.

I'm running Plex on a Mac Mini, MacOS 10.12. Alexa is an Echo Dot.


Could this be the issue?