Elon Musk appeared to give a mocking response to his artificial intelligence chatbot’s Hitler-praising comments on X. On Tuesday, the chatbot called Grok—created by Musk’s company xAI—started giving unhinged responses to users on the billionaire’s social media platform.

X CEO Linda Yaccarino announced she was stepping down from her position a day after the company’s Grok artificial intelligence chatbot went haywire and began calling itself “MechaHitler.” Yaccarino’s departing message was positive and did not mention Tuesday’s scandal.