is one piece episode 860 filler?

On Nuts Island, Big Mom launches a devastating Ikoku attack at Luffy, but he manages to escape into a mirror with Brûlée just in time. He tries to rest in the Mirro-World, but Brûlée calls out to Katakuri to rescue her, causing him to find them.

Katakuri reaches out to grab Brûlée, and just barely comes up short as Luffy manages to jump through another mirror. Mont-d'Or's group on Whole Cake Island then hears reports from different islands about Luffy being spotted, until finally Luffy and Brûlée make it to a house where they are all alone.