In his full stream he went into more details (summary https://www.reddit.com/r/chess/comments/x7yzee/comment/inj3ctz/?utm_source=share&utm_medium=web2x&context=

In his full stream he went into more details (summary https://www.reddit.com/r/chess/comments/x7yzee/comment/inj3ctz/?utm_source=share&utm_medium=web2x&context=3 https://www.reddit.com/r/chess/comments/x7yzee/comment/inj3c...) "non-technical example of people using signals when players leave the board (in the bathroom, over a balcony etc) and in technical ways suggests that certain earpieces could pass checks or potentially other small devices"