Warner Bros. released the trailer for the highly anticipated Joker sequel Tuesday evening—and within hours, YouTube issued a content warning. The warning, which was removed Wednesday afternoon, stated: “The following content may contain suicide or self-harm topics. Viewer discretion is advised.” Before they could watch the Joker: Folie à Deux trailer, users had to click a button saying they understood the warning. The warning may have been issued because of a scene in which Harley Quinn, played by Lady Gaga, mimed shooting herself in the head with a finger-gun, Variety reports. “We determined …