Browser Extension that warns you when you stop following correct opening lines

It can't qualify as cheating - or can it? 
I think such a tool could be present a great learning opportunity as you'd get instant feedback on your mistakes.
At the same time, I recognize that when we take that ability up to some depth of the game, that same feedback might give useful information, in terms of helping decide next mvoes, so I'm torn on this matter.
Can anyone give some opinions on this? And, would one be allowed to monetize, by
Chess.com standards?
Thanks

Even if it's only up to the Book Moves?

You are permitted to use databases (including book openings) in daily games. You cannot use an engine or pre-calculated endgame tablebases, obvs.

I believe use of browser extensions are explicitly prohibited... I'd have to look up the actual wording.

Update: Confirmed! "You may use Opening Explorer or other books in Daily chess only (not in Online / Live play)." No exception is granted for the use of browser extensions (even in daily games).

Cheating since it gives you an evaluation of the position. Like if I were playing a sharp opening and the extension told me my opponent has deviated from theory, I would know to invest some time to punish my opponent

As mentioned, this isn't something that would be allowed outside a daily game. In Daily, it would not be allowed if there were any engine evaluations.

This is also not an appropriate place for discussions about site rules

Well I guess that settles it lol
Thanks for the input guys

On a related note, it feels somewhat wrong the website tells you the opening when you are playing live games, like it even tells you if your opponent fell for the lasker trap in the albin countergambit or if you executed the fried liver in the italian. It isn't as dramatic as an extension that just gives you book moves, but it hasn't always sit right with me you can just see what opening variation you are playing above the moves while in a game (the lasker trap one is the most extreme example as far as I know, outright calling it a trap, which you would then see in game).