E–L_z decoherence of ex situ GC groups due to evolving MW potentials and dynamical friction: normalized total energy as a function of the normalized z-component of the angular momentum at z = 0, colour-coded according to their associations with satellites from the same five MW galaxies shown in Figure 7. The captions provide information on the mass ratio between the satellite galaxy and the MW at the time of the merger (left panel), the redshift (middle panel), and the merger time (right panel).