In April last year, as billions across the globe became extras in Covid’s pestiferous opening act, a 30-year-old actor in California unwittingly carved out an additional role for herself. Ana Coto’s 10-second TikTok clip of herself gliding blithely (and backwardly) along a suburban street to J.Lo’s Jenny from the Block has been viewed more than 16m times. Over the northern summer trend piecespopped up, noting a spike in sales and even a global roller-skate shortage.