In the rich text editor:
@Riles
In a comment:
[Riles](https://chowlings.com/user/Riles)
For Names and Avatars:
In the rich text editor:
%Riles
In a comment:
[![Riles's Avatar](https://chowlings.com/images/avatars/1317.png?v=1646086677)](https://chowlings.com/user/Riles) [Riles](https://chowlings.com/user/Riles)