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