WARNING: Major Spoilers ahead for Star Wars: The Last Jedi! Continue reading at your own risk...
When Disney bought Lucasfilm and began revamping the Star Wars franchise a few years ago, it got rid of all the previous comics and books that made up the extended universe. Everything that came before the acquisition, save for the six films, was no longer canon to the franchise. This includes the old "Dark Empire" comics.
Only the Star Wars comics being printed by Marvel actually count as canon, but it looks like Rian Johnson, writer and director of The Last Jedi, might have reached back into those old "Dark Empire" books to come up with one of the film's biggest twists.
This is where we dive into spoiler territory, just in case you still haven't seen The Last Jedi yet. Now is your chance to get away spoiler-free.
At the end of the film, Luke shows up on Crait, walking out in front of the Resistance base to take on Kylo Ren one-on-one. While the Jedi Master fought his former Padawan, Leia and the others had a chance to escape out of the back of the base. As they made their escape, it was revealed that Luke wasn't actually there at all. He was actually projecting a version of himself onto Crait, making everyone think it was actually his real body. Instead, Luke was still sitting by himself on Ahch-To.
As Reddit user bfett81 points out, Luke pulled off a similar technique in the "Dark Empire" comics.
In the image above, you can see Luke, Leia and Han returning from a dangerous mission. At the end of the scene, Luke reveals that he never actually left the planet Byss. Since he knew that Leia would never let him stay behind, he tricked the entire group into believing that he was with them the entire time.
This doesn't make the previous comics canon by any stretch of the imagination, but, for fans of the series, it is nice to know that the filmmakers are willing to dig back into the old stories to include some of its better content in the movies.