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