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