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