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