Billie Eilish performed her track ‘Happier Than Ever’ on the rooftop of the Hollywood Roosevelt Hotel for Jimmy Kimmel Live! last night (October 13) – you can watch her performance below.The song is the title track from Eilish’s second studio album, which came out back in July.Eilish, her brother and regular collaborator Finneas and their live drummer played ‘Happier Than Ever’ on the rooftop of the Roosevelt, with the trio delivering a powerful rendition of the track.You can watch Eilish’s