In 1995, the EU created a uniform format for an EU visa taking the form of a sticker to be affixed to the travel document of non-EU nationals under visa obligation.
Council Regulation (EC) No 333/2002 of 18 February 2002 for a uniform format for forms for affixing the visa issued by Member States to persons holding travel documents not recognised by the Member State.
Greece do not recognised the Republic of Macedonia until 2018, therefore a Macedonian cannot use his/her passport issued by the Republic of Macedonia to enter Greece.