https://support.chess.com/article/648-what-do-i-need-to-know-about-fair-play-on-chess-com
The site actively reports extensions and works hard on closing accounts that do not follow fair play guidelines.
https://www.chess.com/article/view/online-chess-cheating
https://www.chess.com/article/view/chesscom-update-may-2023#FairPlay
That said, discussions of cheating, potential cheating, or cheat detection are not allowed in the general forums. If you would like to discuss, join the following club:
https://www.chess.com/club/cheating-forum
Genuinely curious, and if they are, is it effective or of no use?
I searched chess.com extensions to see if there were any cool customizations or etc but I found a limitless supply of extensities showing best moves, moving for you, warning for blunders, or etc.
Does chess.com crack down on this?