The issue and reproduction steps:
1. Deploy Social Office. Ensure that your user has the role "Social Office User".
2. Deploy a documents and media portlet on welcome page
3. Upload 4 documents with that portlet
4. Open your dashboard. There should be an announcements portlet and an activity portlet
5. You can see an activity "... uploaded 4 new documents" in the activity portlet
6. Create a new announcement
7. Mark this announcement as read
8. Reload the page
9. Problem: The activity is not visible anymore. If you mark the announcement as unread, the activity will be visible again.