MOSCOW (AP) — Many Russians responded with jokes and skepticism when the team of imprisoned opposition leader Alexei Navalny urged people to shine cellphone flashlights in residential courtyards as a display of unity. After two weekends of nationwide demonstrations, the new protest format looked to some like a retreat. But Russian authorities moved vigorously to extinguish the illuminated protests planned for Sunday. Officials accused Navalny’s allies of acting on NATO’s instructions, broadcasters warned that flashlight rallies had featured in major uprisings elsewhere, and state news agencies claimed a terrorist group was plotting attacks at protests. Such methods represent a change of tactics for the authorities who once tried to weaken Navalny’s influence by erasing him.