In the rich text editor:
@dirt_
In a comment:
[dirt_](https://chowlings.com/user/dirt_)
For Names and Avatars:
In the rich text editor:
%dirt_
In a comment:
[![dirt_'s Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/dirt_) [dirt_](https://chowlings.com/user/dirt_)