Don't forget the great free addon by
@Xon (excellent developer!)
Displays user activity below content. Supported content: Threads Conversations Reports NixFifty's Tickets NixFifty's Calendar It is recommended (but not required) that Redis Cache add-on be installed and configured as the cache provider...
xenforo.com
Best used with his Redis cache addon for better performance.
In the version history you will find a version for XF 2.1