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