We create emails with a QR code. The QR code output is set to png. It looks good and works fine, but in some email (web)clients or when our customers answer this email, there is a mysterious bin file in the attachments , e.g. att1784fe98-0023-41f8-bf5f-6bdfd8afc45a.bin - but only when there is a QR code in the email.
Two questions: 1. Why? Just so I can explain it. 2. Is there any way to get rid of the “bin” attachment?