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