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