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