Adding private repos to the Plugin Manager for company use

I know this is now possible and remember seeing some info about this, but can’t seem to find it back. Any chance I could get a link to the page that explains how to do this?

It is here, at the end of the Extending section, just before the Exporting section:

Just ask if you want to see an example setup.


That’s the page I was thinking about but couldn’t find! Thanks!