Stockholm’s Robin Carlsson is the anomaly. It set the blueprint for a style of “sad pop” that has become a genre of its own, with everyone from Lorde to Troye Sivan writing songs that can move the feet while prompting a tear at the same time. Robyn’s absence, which has included a long-term relationship break-up, the death from cancer of her close friend and musical mentor Christian Falk and years in therapy, has given her plenty more fuel.