In the rich text editor:
@Rhiow
In a comment:
[Rhiow](https://painted-relics.com/user/Rhiow)
For Names and Avatars:
In the rich text editor:
%Rhiow
In a comment:
[](https://painted-relics.com/user/Rhiow) [Rhiow](https://painted-relics.com/user/Rhiow)