In the rich text editor:
@Shima-kun
In a comment:
[Shima-kun](https://chowlings.com/user/Shima-kun)
For Names and Avatars:
In the rich text editor:
%Shima-kun
In a comment:
[](https://chowlings.com/user/Shima-kun) [Shima-kun](https://chowlings.com/user/Shima-kun)
