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