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