The Mastodon site is shown on a smart phone in Oakland, Calif., on Friday, Nov. 11, 2022. Sites like Mastodon and even Tumblr are emerging as new (or renewed) alternatives to Twitter. (Barbara Ortutay/AP) Twitter has been a bit of a mess since billionaire Tesla CEO Elon Musk took the helm, cutting the company’s workforce in half, upending the platform’s verification system, sparring with users over jokes and acknowledging that “dumb things” might happen as he reshapes one of the world’s most high-profile information ecosystems. On Thursday, amid an exodus of senior executives responsible for data privacy, cybersecurity and complying...