Damn that was fast, had my brand new premium top on for about a week and while I was at work a bird sh!t on my rear window. I got home and hosed it off and the damn sh!t was acid etched into the plastic. Not sure what toxic crap the bird was eating but I sure glad I did not get it in my eye lol.
I tried Plexus and Novus. This etched into the window just like you would have taken a branding iron to it. Like I said I have no idea what the heck the bird ate but it was acidic as could be.
Berries are in season right now, birds love them and as you've noticed, it makes their effluent lethal. It does nasty things to clearcoat if you leave it on there, I dread to think what it does to plastic.
Hold my beer and watch this.......
I worked at a GMC dealer about 15 years ago. A bird crapped on the good of a new Sierra Z71, I sprayed it off with a hose and the paint peeled off with the crap. Bare metal was all that was left. The poop couldn't have been there more than half a day.