ActivityStreams protocol spec question

I am confused about something in the activity streams specification
in the Activity Vocabulary doc a Collection.Current can be a PagedCollection or a Link
Activity Vocabulary (

However their example 75 (at link above) current has the “summary” element which is not avalable to something of type “Link” (see below). Am I misunderstanding that current is not an Object or Link but Object AND Link? What do other implementations do with summary in this case?

     "current": {
        "type": "Link",
        "summary": "Most Recent Items",
        "href": ""

This is already mentioned in an issue on the tracker, but it is never addressed. I think you can best assume it is erronous, and belongs to Object.

Update: Changes are staged

Didn’t know about the github issue tracker for activitystreams. Thank you!!