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