One of the most difficult tasks for a window cleaner is to be dealing with dirty windows from broken eggs. Unfortunately, this problem is becoming more and more common, especially if the window cleaner is working at schools and colleges.
After many years of experiences we found a way how to remove it as soon as possible. First of all we need to soak the affected surface with hot water and washing up liquid and leave it for a while, then soak it again and finally scrape it off gently with razor blade. It should come off very easy.