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