After creating a new photos library and trying to make it a system library with "Use as System photo library" I get an infinitely spinning mouse pointer on my MacBook Air M1 with macOS Ventura. How to solve this issue?
MacBook Air (M1, 2020)
I did the same few versions of macOS ago... if you have iCloud turned on for your photos, then the system library will have to be uploaded so it appears on all your devices - which is how it's meant to work.
If you have a lot of photos in your newly created system library then they will all get uploaded to iCloud.
...depending on your upload bandwidth this can take days... yes that's right... days.
Where is the library stored? If on an external that must be formatted Mac OS X Extended, Journaled or apfs.
„Use as System photo library“ causing endless spinning pointer
