evidence: The feud gained renewed widespread attention a week ago when Meta CEO Zuckerberg launched Threads, an app that’s been called a "Twitter killer" by techies, and saw the platform reach 10 million users in the first seven hours. Musk bought Twitter last year for $44 billion. [...] Public bickering between Musk and Zuckerberg first began after Musk’s company SpaceX failed to launch a Facebook satellite that was intended to be used to beam internet access to developing nations in 2016. [...] Fast forward a few years, and the feud heats up. In January, Musk tweeted that Meta-owned Instagram makes people depressed, and in May said that WhatsApp — which Facebook purchased in 2014 — "cannot be trusted."