In the rich text editor:
@N_A
In a comment:
[N_A](https://chowlings.com/user/N_A)
For Names and Avatars:
In the rich text editor:
%N_A
In a comment:
[![N_A's Avatar](https://chowlings.com/images/avatars/1437.png?v=1674320108)](https://chowlings.com/user/N_A) [N_A](https://chowlings.com/user/N_A)