Twitter on Wednesday unveiled – and then almost immediately scrapped – a new grey “official” label for some high-profile accounts as Elon Musk struggles to revamp the highly influential platform following his $44-billion buyout. “I just killed it,” Musk tweeted only hours after the new tag was added to government accounts as well as those of big companies and major media outlets. “Please note that Twitter will do lots of dumb things in coming months. We will keep what works & change what doesn’t,” the world’s richest man added to explain the U-turn. The sudden change of heart will invite furth…