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