Yeah, this tool does not appear to be very good, especially compared to established alternatives. It initially groups files that have the "same extension and s

Yeah, this tool does not appear to be very good, especially compared to established alternatives. It initially groups files that have the "same extension and same size", so you're out of luck if you have two copies named foo.jpg and foo.jpeg. Then, it cheats by computing a crc32 (!) of the beginning, middle, and end bytes of the file and groups together files that have the same crc32. So, it'll mostly work, but miss a lot of duplicates, and potentially flag different files as duplicates.