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