Lumira 2.0 Designer - Esri base map URL?

I have a story in Discovery that uses the Esri base map in a vizualisation.

When I open it in Designer, the URL in properties for the Map component is empty.

Does anyone know what the URL is for the Esri base maps used in Discovery, so I can manually enter it? Presumably we don't lose the ability to use the free base maps in Designer applications?

I also don't seem to be able to find a 2.0 Designer guide, does such a thing exist?