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