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