I need to keep a purchase receipt for several years to ensure the extended warranty on my purchase. How should I store the receipt to make sure it lasts that long? I definitely need a physical receipt, so relying only on a digital copy (or a physical photocopy) is not an option.
It's printed on a thermal paper of some sort. They tend to go black or fade over time. I can can clarify which type if there are further checks I can do with no special equipment.