The death of Shanks foreshadowed.
1) COLORSPREAD OF CHAPTER 874
Shanks is wearing a skull-shaped Khakis which is the 1st death flag on Shanks. If you remember the death of Ace, it was foreshadowed by a card game where Luffy has picked the skull card and lost the game. But there was also a Spade of Ace card in his hand and the face what will do in that scene.
2) CHAPTER 875 COVER PAGE
Bartolomeo is burning up the Jolly Roger of Shanks. As you saw that, when Whitebeard died, his flag was burnt back in Foodvalten by Brownbeard. So the same situaion has occured by Bartolomeo’s flag-burning for calling him for a fight. But that’s either not gonna happen or Shanks just doesn’t want to move his little finger to knock Bartolomeo out.