In the rich text editor:
@K0D9
In a comment:
[K0D9](https://chowlings.com/user/K0D9)
For Names and Avatars:
In the rich text editor:
%K0D9
In a comment:
[![K0D9's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/K0D9) [K0D9](https://chowlings.com/user/K0D9)