In the rich text editor:
@1nka
In a comment:
[1nka](https://chowlings.com/user/1nka)
For Names and Avatars:
In the rich text editor:
%1nka
In a comment:
[![1nka's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/1nka) [1nka](https://chowlings.com/user/1nka)