How to add global configuration settings for all new NGINX hosted websites when using Virtualmin

If you are deploying a lot of NGINX website using Virtualmin, and you need the same configuration value embedded in all new .CONF files, navigate to:

System Settings -> Features and Plugins -> Config (next to Nginx)

See this screenshot, where client_max_body_size 30M; is deployed with each new NGINX website launched.

Reference:
JamieCameron at https://www.virtualmin.com/node/59002