JRC3002

I have a 2019 S560. While recently merging into interstate traffic (under acceleration, merging left), I heard a pop and a crack instantly formed from the top middle of the windshield, horizontally across the drivers side. I did not see or hear a rock and there isn't any signs of something actually hitting the windshield. Has any one heard of unexplained (no event) windshield cracking on this or other Mercedes models? I have had windshields cracked by rocks, but this was different. It did not start small and grow it simply immediately appeared, in full size, simultaneous with the "pop" sound.