While Elon Musk busies himself rebranding Twitter to X, Mark Zuckerberg is getting to work on the jiu-jitsu mat ahead of a potential mega-fight against his billionaire social media rival. The Meta boss, 39, posted images to his own Instagram platform over the weekend showing off his new jiu-jitsu blue belt, as he was presented with a certificate by his colleagues. Zuck is in great shape and regularly shares workout images from his mixed martial arts training, leading to many jabbing Musk that he will have no chance if and when the pair finally meet to do battle. Writing on...