I am starting to explore building SPFX extension (with eventual goal to do a menu in the header for a site collection). I've followed the HelloWorld intro and deployed to my Dev tenant.
Is it documented anywhere yet how to make it scoped to a Site (Site Collection) as opposed to a Web (individual site)?
So based on my reading, it gets packaged and installed as an actual App. In the event I do scope it to a Site Collection, does it matter which site the App is loaded to to activate the CustomAction?
Meaning if I install it on a subsite, will the extension get applied to the root site?