Beta plugins not available for all sites

I’ve really enjoyed some of the beta plugins! I’m curious why they aren’t available for all of my domains.

Specifically, I have a domain www.signallantern.com ( signal.netlify.app ) that doesn’t show up in the drop down when trying to enable beta plugins for sites.

Hi @jrelgin,

The build image of your Site needs to be Ubuntu 16.04 (Xenial) to use Build plugins.
You can set this in the Site settings, under “Build & Deploy” > “Build image selection”.