In the rich text editor:
@PEN_TAGRAM
In a comment:
[PEN_TAGRAM](https://chowlings.com/user/PEN_TAGRAM)
For Names and Avatars:
In the rich text editor:
%PEN_TAGRAM
In a comment:
[](https://chowlings.com/user/PEN_TAGRAM) [PEN_TAGRAM](https://chowlings.com/user/PEN_TAGRAM)