In the rich text editor:
@Viralon
In a comment:
[Viralon](https://chowlings.com/user/Viralon)
For Names and Avatars:
In the rich text editor:
%Viralon
In a comment:
[](https://chowlings.com/user/Viralon) [Viralon](https://chowlings.com/user/Viralon)