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