Prince William and Prince Harry secretly visited Pinewood Studios in April 2016 to shoot cameos in "The Last Jedi," but it later emerged that the scenes had been cut from the film. It was rumored that the princes were too tall. William is 6'3". Harry is 6'1". Stormtroopers are typically required to be 5 foot 11.
The brothers, who are apparently huge Star Wars fans, attended the premiere of the film in December 2017.
Luckily for dissappointed fans (me included), a deleted scene from the film is now on YouTube and is believed to feature stormtrooper Prince William (far left in the scene) next to Prince Harry and actor Tom Hardy. The trio are shown in a lift with Finn (John Boyega), Rose (Kelly Marie Tran), and DJ (Benicio Del Toro). It's Tom Hardy's stormtrooper that does the talking.
The clip will reportedly feature as an outtake on the film's DVD, which is set to be released on April 9.