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