Lxplus ROOT installation not showing graphics from Python

When connecting to lxplus via:

ssh -Y etejedor@lxplus.cern.ch

If the ROOT installation on the lxplus node is used, when trying to open a window with ROOT graphics from Python:

>>> import ROOT

>>> c = ROOT.TCanvas("c")

no graphics are shown. The graphics do show if the ROOT installation on CVMFS (LCG 98) is used instead. When checking their versions with root --version, both the ROOT installation on the lxplus node and the one in LCG 98 report to be 6.22.00.

Mentioning ellert as the ROOT package manager for EPEL.