My Nissan camper van is parked on my drive very close to some shrubbery. It has reflective privacy glass on the rear 4 side windows and a pair of Goldcrest regularly display against their own reflections. As they can’t see inside the vehicle I can sit there with them just a few inches from my nose and watch their antics. Unfortunately it’s almost impossible to photograph through the glass as it is very dark and disrupts the AF and the birds are too twitchy and fast to MF accurately. However they were so animated in their displays to allow me to approach from outside the camper and get a some shots, again not easy for AF due to their rapid movements.
This one was taken through the glass so just a record shot
I have now hung some cloth from the top of the window to avoid the conflict!