Antonio Brown is going way too far with his most recent Twitter antics ... sharing an insensitive image making fun of mental disability on Monday -- and people are pissed.
AB has had zero filter on social media lately ... firing tweets with seemingly no care about the repercussions, including tasteless jokes about Tom Brady's marriage issues with Gisele Bündchen.
34-year-old Brown randomly decided to post the offensive picture just minutes ago ... showing a distorted image of the Arizona Cardinals logo and a modification of the team name that featured the R word.