Taylor Swift appears to have dropped a hint at who she’s backing for US president – and it looks like it could be Kamala Harris.

Speculation began after the pop megastar posted a collection of pictures on her Instagram page on Tuesday from her three performances on consecutive nights in Warsaw during her Eras tour.

On the seventh slide – a picture of her onstage playing guitar – there is a silhouette of what looks like Harris, the Democratic Party’s nominee, also onstage, waving…