Screen flashes after iOS system prompt closes

When using Prime 31's StoreKit plugin I've noticed the screen briefly flashing with an image from a previously loaded scene. This seems to happen whenever one of the iOS system prompts is closed (ie. the login or purchase prompts). Prime 31 has said that this is an issue on Unity's end. Is there any way to fix this? I've tried using GL.Clear() but it didn't have any effect.