Using third-party apps to remove duplicate photos might damage your Photos for macOS library
Apple recommends that you avoid using certain third-party apps that can damage your photo library on your Mac.
Some third-party apps for your Mac that claim to clean, shrink, de-clutter, or remove duplicates from Photos can instead damage your photo library or delete pictures and related data.
You can avoid damage to your library by organizing and managing your pictures from within Photos.
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