I just tested primal with many black QR Codes. It read them all correctly. So, I don't know what the problem is.
Ugh. Standards. Maybe the safer option would be to don't do inverted QRs if it's badly supported?
Primal app couldn't scan any, and some other clients only with difficulty. nostr:nprofile1qqsdv8emcke7k3qqaldwv956tstu40ejg663gdsaayuuujs6pknw7jspp4mhxue69uhkummn9ekx7mqpr3mhxue69uhkummnw3ezucnfw33k76twv4ezuum0vd5kzmqpzfmhxue69uhhqatjwpkx2urpvuhx2uc86mqq0