We just got back from Rome via Frankfurt to the US and we detaxed in Rome since our layover time in Frankfurt was under 2 hours. I had looked up and you can detax in your first airport in Europe as long as you don’t spend more days in Europe and have a connecting flight out of Europe
Thank you very much! I'm hoping I can do it in Nice and not Frankfurt, since they have those same kiosks that are in Paris. Makes it super convenient!