(Could we prove that a cookie can actually contains personal data, let's say, if the same cookie is spread among enough websites and track everything you do ?)
For example, the proposal clarifies that no consent is needed for non-privacy intrusive cookies improving internet experience (e.g. to remember shopping cart history) or cookies used by a website to count the number of visitors.
[1] https://ec.europa.eu/digital-single-market/en/news/proposal-...
What kind of other solution do you think about ?
You could do something like an iFrame, with the parent site passing information to the frame. Here's an example: https://medium.com/building-contently/tracking-people-across...
Same question: this iFrame would be used to store information related to the user across websites, it kind of works like a cross-domain-cookie-replacement : could GDPR make these kind of tooling illegal ? Should we display a very specific popup to tell the user what those scripts really do ? And have an opt-out option ?