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