The Brief: "Extra" is a slang term meaning that someone's personality or behavior is over-the-top or excessive.

DEEP DIVE
“Extra” is a slang term meaning that someone’s personality, style, or behavior is over-the-top or excessive. Someone who can be extra-organized, extra-glamorous, or extra-fierce, may also be generally “extra.”
The term is often associated with being a diva and celebrities including Rihanna, Jeffree Star, DJ Khaled, and Cardi B.
Some examples of people being extra:
Blue Ivy is a whole MOOD. pic.twitter.com/MVqj2IwwgG
— β¨ππ (@mayathemuse) July 26, 2018