In the rich text editor:
@18mystxcs
In a comment:
[18mystxcs](https://chowlings.com/user/18mystxcs)
For Names and Avatars:
In the rich text editor:
%18mystxcs
In a comment:
[](https://chowlings.com/user/18mystxcs) [18mystxcs](https://chowlings.com/user/18mystxcs)