
(The QR code spec requires a border at least 4*box_size thick but we can't just set border=16 because that results in a QR code more than 255px tall and I'm not yet ready to use fullimage() as a backend for it)
(The QR code spec requires a border at least 4*box_size thick but we can't just set border=16 because that results in a QR code more than 255px tall and I'm not yet ready to use fullimage() as a backend for it)