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