Guess what Baruto's painted in the Hokage's monuments Head stones
it's One Piece Straw Hat Pirates' jolly roger,
a reference to competing Weekly Shōnen Jump manga One Piece by Eiichiro Oda. In return, the cover art of One Piece's chapter 766 references Naruto, and in the week's author comments section, Oda thanks Kishimoto for being his friend and rival.
The other authors for the Weekly Shōnen Jump series say their farewell words to Kishimoto for finishing his work in their weekly comments.