In the rich text editor:
@Glo
In a comment:
[Glo](https://cometcrashers.org/user/Glo)
For Names and Avatars:
In the rich text editor:
%Glo
In a comment:
[](https://cometcrashers.org/user/Glo) [Glo](https://cometcrashers.org/user/Glo)