You are referring to this clause, correct?

"attaching a link associated with at least one of the activities of another user to at least one of the plurality of news items where the link enables a viewing user to participate in the same activity as the another user"

The github news feed includes notifications of comments, and there is a link that can be used to go to the comment page and also comment. As I'm reading clause, the link itself doesn't need to actually cause an action, and the link in that github news item "enables a viewing user to participate in the same activity as the another user."

Also, you can edit and make commits from the web interface, so this could fall under this as well.