In the rich text editor:
@T0N618
In a comment:
[T0N618](https://chowlings.com/user/T0N618)
For Names and Avatars:
In the rich text editor:
%T0N618
In a comment:
[](https://chowlings.com/user/T0N618) [T0N618](https://chowlings.com/user/T0N618)