Since day one I own my scala (sept 20) I've noticed traces of some liquid poured and dried on my windscreen at the passenger side. Thought it would disappear by it self after few rainy days and several wipes. But no... Today I also realised there was once some kind of triangular sticker and it left its trace on the windscreen. Like a negative siluete or something, maybe when the car was stored under the sky and sun? 

Does someone know what it is and how do I clean / remove it? To me it looks like it's in the glass and impossible for removal. Could it be? 

I attached a photo I took this evening at my parking place. Near the light reflection you can spot a big Z  with numbers below, something like 09-2...

Thank you for your responses. 

Gary. 

If you can not clean it and remove so you do not see with household products you might have like vinegar, nail varnish remover or white spirits then have the dealership you got it from do it to your satisfaction.

It is some sort of transit location sticker, probably stuck on at a dockside compound.

 

I would be asking the supplying dealer to remove the gummy residue as car should have been prepared (which includes cleaning) before handover

 

If you dealer is long way away, to clean the glass take a cotton wool pad, and try white vinegar, or glass cleaner, or alcohol (vodka aledgedly also works), or paint brush cleaner.   If it goes slimy then few spots of washing up liquid to degrease it).   Don’t use some of these on paint

Try CRC