When I connect my iPhone to my MacBook, Photos suggests to import "new objects". As both devices are synced against iCloud and always updated by the minute, it's pretty annoying. The logic thing to do, is to do as Photos suggest, but only resulting in a massive amount of duplicates. Just a few of them is in the heic-format. When I discovered this at some point I had accumulated thousands of duplicates in Photos, some files with up to 10 duplicates. On top of that, most duplicates had great differences in file sizes, and many with meta data in one/some of the files. **** of a job to clean up....
I actually did an import of all 7000+ suggested files into a new album in Photos, then deleted all of them, and thought that would solve the issue. Well, no, Photos still suggests importing 3200 files.
I don't think clean installing either my iPhone or MacBook or even both would solve it either, but if anyone has done this and thus solved the problem, please tell!