German police detained a suspected Taylor Swift stalker before the US superstar kicked off the German leg of her record-breaking Eras Tour in the western city of Gelsenkirchen on Wednesday evening. The man had made threats against the singer, a police spokeswoman said early on Thursday, without providing further details. Overall, the concert on Wednesday was a peaceful event attended by some 60,000 visitors, the statement said. A police operation involving a separate incident caused delays as fans were leaving the venue after the concert, police said. A 70-year-old man had called the police fo…