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