Google AI invents its own cryptographic algorithm 10 years ago
TFA's title is a little clickbaity by adding "noone knows how it works" which apparently means that:
The researchers didn't perform an exhaustive analysis of the encryption methods devised by Alice and Bob, but for one specific training run they observed that it was both key- and plaintext-dependent. "However, it is not simply XOR. In particular, the output values are often floating-point values other than 0 and 1," they said.
Just saying...