In the rich text editor:
@Unicorn-Panda
In a comment:
[Unicorn-Panda](https://www.worldofgaia.org/user/Unicorn-Panda)
For Names and Avatars:
In the rich text editor:
%Unicorn-Panda
In a comment:
[](https://www.worldofgaia.org/user/Unicorn-Panda) [Unicorn-Panda](https://www.worldofgaia.org/user/Unicorn-Panda)