In Denmark, all traffic signals have red-yellow. For buses, the "S" corresponds to the red, the "-" corresponds to yellow, and "|" or "/" corresponds to green. They light up in the same phases.
Some signals don't have any visors, especially the new LED signals at intersections along the Strøget. Unfortunately I have only one photo at this time, but more similar ones are to be coming soon.
København Rådhus, central Copenhagen
København Hans Christensen Andersens Boulevard, central Copenhagen
København corner of Strøget and Radhusstræde