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