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