The coefficients $v_3^0$ (left) and $k$ (right) from fits of Eq. \eqref{eq:v3v2} to the $v_2\{2\}$--$v_3\{2\}$ correlation shown in Fig. \ref{fig:v2v3cor} for Pb--Pb (solid red markers) and Xe--Xe (open red markers) collisions as a function of the collision centrality. Xe--Xe points are slightly shifted horizontally. Measurements from the ATLAS Collaboration in Ref.  (black points) are shown for charged particles in the kinematic range $0.5 p_\mathrm{T} 2.0 \text{GeV}/c$ and $|\eta| 2.5$. Error bars (boxes) indicate statistical (systematic) uncertainties.