It’s automatically created as soon as a QR-Code is saved.
The image embeds the standard URL, which includes the QR-Code key, a parameter that should not be changed. In fact, modifying the key will also change the QR code image and the value stored in the logs key column.
Enhanced
It can be created manually by clicking a dedicated button on the QR-Code Editing page, or automatically via the image display shortcode.
The image embeds a complex URL (i.e. not easily readable by humans) and, unlike the standard image, it can be regenerated without changing the QR-Code key.
It is particularly useful when you need to update the QR code image frequently and/or to prevent users from easily sharing the QR-Code URL with others (e.g. when using content hiding).
Tip
Read here if you need to change frequently the QR code image.