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