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