@Alby something wrong with Alby hub? My umbrel is fully operational but Alby Hub isn’t. No outbound transactions. Invoices can’t be created. That’s for Alby Go, Browser Extension as well as on umbrel.
I discovered a perfect usecase for blink vouchers which is tipping housekeeping at check out of a hotel. Since you usually don‘t meet the guys in person you have to use something that is not cash (fiat), doesn’t require them to leave their QR-Code somewhere somehow which might get them into trouble and is still disposable. (Giftcards/Boltcards wouldn’t therefore be a good alternative). A small disposable piece of paper is ideal.