Top panel: Charged particle $v_{\rm n}$ integrated over the transverse momentum range $0.2< p_{\rm{T}} < 3.0$ GeV/$c$ as a function of centrality from Xe--Xe collisions. The various techniques are explained in the text. Only statistical uncertainties are visible (thin vertical lines). Bottom panel: Ratios of $v_{2}\{4\}$/$v_{2}\{2\}$ compared to some theoretical predictions. The hydrodynamic predictions use a shear viscosity over entropy ratio $\eta/s=0.047$ and initial conditions from the T$_{\rm{R}}$ENTo model . For $v_{2}\{2\}$, the ALICE measurements implement a $|\Delta\eta|>2.0$ gap which is not used in the models.