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