Thanks… This links to the fire-app-builder, which is the basis of my current app that’s not working on 4k Gen 2 (everything is fine except the AMZNMediaPlayer is crashing when attempting to play a video. I’ve submitted a topic here for that I get error with only Firestick 4K (Gen 2) - #2 by Levon). It almost seems like the upgrade in the Fire OS version broke the fire-app-builder because my app works everywhere else.
I guess I could look at building a generic android tv app to see if it works.
Thanks for responding.