Drive should synchronise collections in synchronized folders

Collection sync is enabled with https://doc.nuxeo.com/x/GoAlAQ. Tested OK when direct sync of a collection.
But if I sync a Folder that as a Collection in it, it doesn't sync the collection. And it won't work either if I force the sync of the collection by clicking on the collection sync action itself (which shouldn't be here as the parent is already sync'ed).

Drive build: 2.0.0805