The contribution of the linear and nonlinear flow modes of $v_4$ extracted via multiparticle correlations (solid red and blue points) and using the ESE (open red and blue points), as well as the unbiased $v_4\{2,|\Delta\eta|>1.0\}$ (black points), as a function of centrality in Pb--Pb collisions. Error bars (boxes) indicate statistical (systematic) uncertainties.