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