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