Cheating issues

I think it's obvious that we have players with skillful cheating methods. Skillful I would define as 'not recognized by lichess as cheating'.
I would like that you share in this post your experiences regarding this matter, maybe even skillful method(s) if you know some. At the end maybe this could help lichess to develop better cheating recognition techniques.
Now I will not write my example because I already did it yesterday in the sarcastic post ' The honest player'.
Glad to see your comments.

And you think users lacking the relevant (meta) data see more than a well-trained AI?

„ Instead these systems are based more on probability. Big websites have millions of games to analyse - including games with confirmed GMs to learn from. A fraud detection algorithm can consider unlimited questions like:

If black has a 3 pawn lead but lots of unguarded pieces and down a knight, how likely are they to aggressively recapture instead of defend?
If black has been playing aggressively, how likely are they to play a very difficult to calculate defensive move?
When black has 15 available moves, 10 of which are pretty good, how long will it take for black to play a move?
Black has played 20 straight GM level moves and has a strong material lead. What are the odds that black will now play an amateur blunder? A "look I'm not cheating" move?
Is black suddenly playing like a GM whenever there's one really important move?
Does black suddenly play very well mid game if they are slightly behind? How likely is a human to do that?
Is black playing hard to calculate moves just as fast as easy to calculate recaptures?“

If Lichess doesn't recognize it, how can it be obvious?

As far as I know, Lichess' methods of detecting cheats are way better anything a normal player could hope for.

I think that Lichess can enforce some constraints to the player while in the game, for example, if you change tab / window / app during the game you will be cosidered as someone who left the game.
Cuase most cheaters use to Switch between apps or Browsers i guess maybe?!

Someone named syaaaaaaaaaaaaa tell me also he's using cheat on our game ... not fair ....

@matar770 how would Lichess obtain information that you switched tab or switced to an app? There is thing called privace which operating system try to protect. Lichess can get only information on what happen on that tab. And obviously can detect double logins but thats about it

Lichess does detect that you switched away from the tab or window, it just can't tell what you switched to.

But if your moves are consistently more accurate when you switch away than when you don't, it's an indicator of cheating.

It's more detecting that you're not focused on that tab anymore than detecting that you're doing something else (that just stands to reason). It's not an invasion of privacy for Lichess to detect when you are or are not engaged with their site whether it be through the standard 'has focus/blur' methods in scripts or native page visibility APIs which are part of most browsers. I usually have something on in the background in case I've become sure of a position or my opponent is running down the clock on purpose. Lichess doesn't care if you go to other tabs or applications as long as you don't come back with a nonsensical engine move. As stated before, they just know you're not focused on their page anymore, not what you're doing. I'm sure there are ways of just using an overlay on the page to achieve the same effect, and even programs to move the pieces for you. It doesn't matter. They have a lot of game data to go by, and yes, sometimes it could take several games to establish a pattern of abuse, but eventually, they will get caught. I'm not saying it catches every instance of cheating like someone looking up a move on their phone in one game ever and it is your privilege to contact Lichess if you think a false detection has occurred. There is also a report button to get a human on the case. I'm not sure what you want. Do you want Lichess to pay a bunch of money to some company to develop new heuristics as did to maybe detect it a little bit faster? Even they still rely on a human for the final decision.