What you are seeing here is a NESA window, it stands for Non Electro Static Formulation. They use a layer of stannic oxide, a thermistor, and a layer of vinyl. The window is electrically heated to prevent ice formation and also prevents shattering in the case of a bird strike. Some malfunction took place here. Some pilots would sometimes land with the power to the window still on and after a long taxi it would destroy windows in this fashion.
Airplane Windshield Cracking in Flight