In the rich text editor:
@catpuppy0_o
In a comment:
[catpuppy0_o](https://chowlings.com/user/catpuppy0_o)
For Names and Avatars:
In the rich text editor:
%catpuppy0_o
In a comment:
[![catpuppy0_o's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/catpuppy0_o) [catpuppy0_o](https://chowlings.com/user/catpuppy0_o)