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