Hello Renan,
I am not really sure where you want that feature or how you want it to work, are you talking about tagging people in comments? what do you think should happen when a person is “mentioned”?
When you create a new “post” you can include people, but there is no inline lookup in the edit fields and this is not something I have in my todo.
I am always open for new ideas how to improve intrapages. a detailed description is always helpful
Yours Truly
Thomas