Santa lights the Square at Ghirardelli Square on Friday, November 27, the day after Thanksgiving, with the grand lighting of the 46-foot Christmas tree at 4:45pm. The San Francisco Boys Chorus performs, then Santa and his elf lead a sing-along. It's free and all ages, so get there before 4:45pm for a good viewing spot Santa and Elf visits also run 4:00-7:00 PM on Fridays December 4, 11, and 18. F…