SPOILERS BELOW!

I’ve been seeing a theory flying around that White Diamond is blind, and uses her pearl to see throughout. Now, I’ve been believing that our pearl was once, in the past, White Diamond’s pearl for a very long time. If the theory that White Diamond was seeing out of her pearl’s eyes for sight, then that could mean that White Diamond could see out of OUR Pearl’s eyes. She would have seen EVERYTHING. Thats why White didn’t seem so fazed when Steven appeared in front of her. Because she already knew.