Article continues below advertisementKate Middleton debuted a new hair color, and social media users aren't impressed.The royal, 43, stepped out on Thursday, September 4, with fresh blonde locks while visiting the Natural History Museum's newly renovated gardens in London.Middleton's previously-brown hair appeared to have highlights in it, leading several to believe she could be wearing a wig.Article continues below advertisementKate Middleton's New HairSource: MEGAKate Middleton's hair was previously brunette."That's a wig...