I've just started getting an issue with LR Classic where it thinks there are 2 copies of each file on my memory card. I've just spent a madeningly frustating hour on the phone to Adobe Support and didn't get anywhere.
My workflow is to create a new catalogue for each project. Insert the CF card fresh from my camera and import the images directy from memory card to an external USB drive. The images have not previously been imported to this or any other catalogue. Mac finder shows only one copy of each file on the memory card as does Capture One.
I know I can click the 'do not import suspected duplicates button' but it's still annoying nonetheless.