evidence: The battle between Mark Zuckerberg's Threads and Elon Musk's Twitter is heating up — Twitter is threatening to sue Meta for "systematic, willful, and unlawful misappropriation of Twitter's trade secrets and other intellectual property." [...] The legal threat is just the latest news in the ongoing feud between Zuckerberg and Musk. Last month, the billionaires took it as far as proposing a cage-fighting match.