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