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