In the rich text editor:
@Rokkusuta00
In a comment:
[Rokkusuta00](https://chowlings.com/user/Rokkusuta00)
For Names and Avatars:
In the rich text editor:
%Rokkusuta00
In a comment:
[](https://chowlings.com/user/Rokkusuta00) [Rokkusuta00](https://chowlings.com/user/Rokkusuta00)