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