In the rich text editor:
@DawnOfNight
In a comment:
[DawnOfNight](https://chowlings.com/user/DawnOfNight)
For Names and Avatars:
In the rich text editor:
%DawnOfNight
In a comment:
[](https://chowlings.com/user/DawnOfNight) [DawnOfNight](https://chowlings.com/user/DawnOfNight)