Cracked window rock guard

Arrived at our destination today to discover a starburst-type fracture about the size of a quarter in the smoked rock guard over the big front window of our 2013 Flying Cloud. What is the best course of action for this mishap? Do people leave it as is? Is there some sort of repair, similar to windshield repairs that should be done? Do these things tend to spread, as they will do in an automobile windshield?

Thanks for your advice.