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