Fill small window cracks with nail polish
A windshield can easily be chipped by small stones or debris. This mostly happens on highways when you are driving behind trucks. Their large treads can pick up rocks, and they spring out at high speed directly onto your windshield.
This will most likely cause a small chip. It’s essential to prevent it from becoming larger because chips tend to expand and become larger cracks. The quickest fix is to put some clear polish on it. It will be invisible when it dries up, and it will prevent the crack from expanding.