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