This is on the brink of bug/improvement, but I am marking it as a major bug as it caused some people a lot of confusion (they assumed a bug).

To reproduce.

• On front page, pick any (normal user) from Site pages > Participants list
• Select Users > (User's name) > Reports > Complete report
• The main content pane is completely empty.

Granted, there is no activity on the front page but it looks broken. It should print a message to say "no activity found" or such.