DRESDEN, Germany — Just over 15,000 people gathered at the Elbe River bank on Sunday, some donned in sunnies and carrying sauce-laden brätwurst from pop-up food carts, though all took pause around 11:14:59 a.m. It wasn’t to take in the Altstadt baroque-style buildings that make up the city skyline, nor was it to bask in the bright, mid-morning sun hovering on the horizon. A new attraction had come to the capital city, and all eyes...