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