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