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