The Computer Wore Menace Shoes - S12-E6
Trivia: Although Homer claims not to have a computer, he used one in the episode "King-Size Homer" when he was assigned to work at home due to his hyper-obesity. However, this was installed by (and likely remained the property of) Mr. Burns. In "El Viaje Misterioso de Nuestro Jomer", the "Space Coyote" instructed him to get more possessions, and reminded him that he did not even own a computer. On the other hand, during the meteor shower in "'Scuse Me While I Miss the Sky", Marge makes a reference to a screensaver, implying that they do own a computer ("This is even better than our screensaver. And I love our screensaver.").
The Computer Wore Menace Shoes - S12-E6
Trivia: In this episode, Homer has made a very popular website. You can actually visit the site at this URL: http://www.thesimpsons.com/mrx/.
Answer: I'm not sure if this is the one you're thinking of, but an episode of "Ray Bradbury Theatre," called "A Sound of Thunder," dealt with a similar matter: a group of hunters travel back in time to hunt dinosaurs, only to find things have changed when they get back because someone stepped on a butterfly.
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