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