Stay offline, Avengers directors warn fans

This image released by Marvel Studios shows, front row from left, Danai Gurira, Chadwick Boseman, Chris Evans, Scarlet Johansson and Sebastian Stan in a scene from "Avengers: Infinity War," premiering on April 27. Image: Chuck Zlotnick/Marvel Studios via APAhead of the Avengers: Infinity War world premiere in Los Angeles on...