Left, top: $p_{\rm T}$-differential cross section of electrons from heavy-flavour hadron decays in pp collisions at $\sqrt{s} =$ 13 TeV measured at midrapidity with different detectors and data sets. Left, bottom: Ratios of the different measurements in the overlapping \pt intervals. Right: $p_{\rm{T}}$-differential cross section compared with Fixed Order with Next-to-Leading-Log resummation (FONLL)~ and General-mass-variable-flavour-number-Scheme (GM-VFNS)~ predictions and its ratios with respect to FONLL and GM-VFNS central values in the two lower panels. Vertical bars and boxes denote statistical and systematical uncertainties, respectively.