In the rich text editor:
@Poppln
In a comment:
[Poppln](https://chowlings.com/user/Poppln)
For Names and Avatars:
In the rich text editor:
%Poppln
In a comment:
[![Poppln's Avatar](https://chowlings.com/images/avatars/341.jpeg?v=1644063280)](https://chowlings.com/user/Poppln) [Poppln](https://chowlings.com/user/Poppln)