What is this icon and what makes the top entry different from the bottom?

I see a side-by-side icon next to some items in DEVONThink and I don’t know what it means. These two items appear to be exactly the same as I preview them, but I don’t know what this icon means. Can anyone explain?

It means it’s a duplicate, as noted in Help > Documentation > Appendix > Iconology

Thank you

You’re welcome :slight_smile: