PHOTOBOMB is validvalid

to appear suddenly in a photo as it is being taken [v PHOTOBOMBED, PHOTOBOMBING, PHOTOBOMBS] : PHOTOBOMBER [n]

108,892 of 196,601 in NWL2023·also valid in CSW24

to place oneself in the background of a photograph deliberately and without the knowledge of the photographer or subject [v -ED, -ING, -S]