In a wooded cemetery in Munich, a white sticker with a puzzling QR code appeared on a gravestone late last year. Then, over the next few weeks, more and more stickers mysteriously appeared, until more than 1,

More than 1,000 stickers were put on gravestones and wooden crosses at three cemeteries in the German city, without any indication of where they came from or why. The 5×3.5-centimeter (1.95×1.2-inch) stickers are printed with a QR code,

More than 1,000 stickers have appeared on gravestones at three cemeteries in Munich, Germany, without any indication of where they came from or why, sparking a police investigation