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