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