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