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