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