VCF files are a web standard since almost 30 years, since Outlook Express or even earlier.
From the wikipedia: vCard, also known as VCF, is a file format standard for electronic business cards. vCards can be attached to e-mail messages, sent via Multimedia Messaging Service, on the World Wide Web, instant messaging, NFC or through QR code. They can contain name and address information, phone numbers, e-mail addresses, URLs, logos, photographs, and audio clips.
https://en.wikipedia.org/wiki/VCard
Its a shame that Acymailing cant handle them.