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