In the rich text editor:
@CrystalChrissy
In a comment:
[CrystalChrissy](https://chowlings.com/user/CrystalChrissy)
For Names and Avatars:
In the rich text editor:
%CrystalChrissy
In a comment:
[![CrystalChrissy's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/CrystalChrissy) [CrystalChrissy](https://chowlings.com/user/CrystalChrissy)