is one piece episode 882 filler?

Sengoku continues his memories about what happened at Marineford two years ago. Luffy and the escaped prisoners join the Whitebeard Pirates and battles against the Marines.

To the shock of everyone, Luffy unintentionally uses Supreme King Haki, knocking out everyone in the vicinity. He rescues Ace and they prepare to escape, but Ace is unfortunately killed by Akainu.

Whitebeard would also lose his life in this war. Back to present day, many of the monarchs around the world gather at Mary Geoise for the Levely.