More information is in Opinion 04/2012 on Cookie Consent Exemption of the Article 29 Working Party of the European Commission about Cookie Consent, which elaborates about the topic:
(The ยง29 WP is now replaced by the European Data Protection Board, but that seems not to have issued any more current Guidelines or Opinions on that matter. Maybe they are waiting for a forthcoming ePrivacy Regulation. Also: IANAL.)
https://ec.europa.eu/justice/article-29/documentation/opinio...
(The ยง29 WP is now replaced by the European Data Protection Board, but that seems not to have issued any more current Guidelines or Opinions on that matter. Maybe they are waiting for a forthcoming ePrivacy Regulation. Also: IANAL.)