Alright WTF. I've got something stuck to my windshield that I can't get off. Another problem is, you can't see it unless I have the wipers on. I don't know if it's tree sap, oil, etc. When the wipers pass over it leaves these 'spots' all over. They look like dried raindrops kinda. They appear after the wipers pass over, then fade as they dry. You cannot see them when the window is dry - it fades into non-existance. I've tried amonia based window cleander, rubbing compound, even a razor-blade window scraper, it won't go away. I even replaced my wipers - no change. What is this crap and more importantly how the hell do I get it to go away.