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