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