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