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