texture.loadImage() extension method from UnityEngine.ImageConversion crashes app in unity 2017.3.1f1 but works fine in 2017.3.0b10

When I call loadImage method in IOS build made from unity 2017.3.1f1 my app crashes but it works fine in unity 2017.3.0b10. But in unity 2017.3.0b10 on switching scene, scene freezes and stretches but this issue is fixed in unity 2017.3.1f1. I will be grateful if someone could help me here!