Photobomb
From Tardis Wiki, the free Doctor Who reference
The Thirteenth Doctor photobombed the photograph taken of the newly crowned Queen Elizabeth II and her family on the balcony of Buckingham Palace on 2 June 1953. (COMIC: Where's the Doctor?)
Behind the scenes
Technically speaking, the Doctor has "photobombed" various historical photos before. However, the instance shown in Where's the Doctor? is the first time it had been identified as such in-universe.