Taking this marvellous question as inspiration, I travel a lot by car, often in countries that require me to buy a vignettevignette to use the motorways. Moreover it is usually mandatory to stick the vignette inside the windshield of the car, to prevent re-use. However, these vignettes are designed to tear off in mosaic-sized pieces as soon as one attempts to remove them, this too probably to prevent re-use.
Since I am fed up of collecting vignettes from various countries and solar years, I would like to start removing all the unnecessary ones. Is there a smart and effective way to remove these tough stickers from the inside of my car wind-shield without damaging neither it nor the car?