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