Recently I played with the current #4 in the rating list, zisezhuya, who appears to be quite a strong player but using a peculiarity of the move confirmation to cheat when the game goes wrong for him. He proposes to abandon, but if you disagree, he lets time go off and (attention!) you can't expel the opponent - every time you try it, he starts placing some tiles without move confirmation.
I checked it, and during last three days since our game he used this cheat three times - when his opponents were getting better board or KT6 in 2019 edition:
https://boardgamearena.com/gamereview?table=264122774
https://boardgamearena.com/gamereview?table=264155743
https://boardgamearena.com/gamereview?table=264252484
This is a clear cheating approach in CoB, which everybody can use and get much much better results.
I checked it, and during last three days since our game he used this cheat three times - when his opponents were getting better board or KT6 in 2019 edition:
https://boardgamearena.com/gamereview?table=264122774
https://boardgamearena.com/gamereview?table=264155743
https://boardgamearena.com/gamereview?table=264252484
This is a clear cheating approach in CoB, which everybody can use and get much much better results.