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