Hello, I have the photos app set to reference a library on a storage drive instead of locally (bought the 128 gig macbook air...) to save space on my actual mac. But when I check the storage tab in about my mac, locally photos is still using 20 gigs of space. Does anyone know how to get rid of that? Thoughts? Update: hmm, when i unplug my drive it says the 20 gigs is actually system files. Maybe this is some kind of glitch with how macos sierra categorizes space.