#1 First they filmed him driving down the street from a car next to him and the rear-view mirror is there because laws and safety. Then they filmed him from the back seat while not actually driving and using cgi/green screen. For this they had to take out the mirror so you wouldn't see the camera dude. You can also notice that the steering wheel doesn't match up to his driving. All this is very common.
In ‘Harry Potter and the Prisoner of Azkaban,’ both Daniel Radcliffe and Emma Watson can be seen wearing battery packs on their backs as they try to sneak to Hagrid’s Hut to save Buckbeak.
#1 First they filmed him driving down the street from a car next to him and the rear-view mirror is there because laws and safety. Then they filmed him from the back seat while not actually driving and using cgi/green screen. For this they had to take out the mirror so you wouldn't see the camera dude. You can also notice that the steering wheel doesn't match up to his driving. All this is very common.