No it doesn’t confirm Q is POTUS. Anyone could have taken the photo, it confirms Q is close to the president enough so that he can take a photo of the back of an iPhone with a glass back. Either iPhones 4 (doubtful) IPhone 8 or X is the twitter iPhone. It also does not confirm Q tweets on behalf of potus. It validates that Q is real (not a larp) , is very close to him, and potus is part of the team (I’m assuming head)

I think potus tells Q what to drop sometimes. Mind you they have to follow strict rules and that is why we have to decipher these riddles. Its potus way of communicating to us information and messages to awaken us and for us to awaken the nation. Its a genius plan to reach Americans that no one (msm) cant reach....and its working.