In the rich text editor:
@beetleparty
In a comment:
[beetleparty](https://chowlings.com/user/beetleparty)
For Names and Avatars:
In the rich text editor:
%beetleparty
In a comment:
[](https://chowlings.com/user/beetleparty) [beetleparty](https://chowlings.com/user/beetleparty)