Relative acceptance correction factor $R$ as a function of $m_{\rm ee}$ and $p_{\rm {T,ee}}$ (left panel) and as a function of $m_{\rm ee}$ integrated over $p_{\rm {T,ee}}$ (right panel) in the 10% most central Pb$-$Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV. Statistical uncertainties are represented by vertical bars.