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