Article continues below advertisementCould Britney Spears be warming up her vocals for a comeback?The pop star, 43, belted out an unidentifiable track in a chaotic video on Monday, August 4.Article continues below advertisementBritney Spears Is Singing AgainSource: @britneyspears/InstagramBritney Spears belted out a song from her room.Spears strutted around her room in a sheer white slip dress that was falling off her shoulders as she belted out a song. The lyrics of the tune could not be deciphered, but the singer flexed her vocal prowess by riffing notes.