I thought some kids put a green plastic bag up a tree as a joke, but looking around, I found every tree had one. All the trees on Trafalgar Street have fairly (Christmas) lights, so these bags must store the ... whatever they store to make the lights work. You can see the power line hanging from the bag.
Quite inadvertently, I caught a glimpse of THE stained glass at the museum. This was also the very first shot on my new camera.