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