[Chimera-users] Distance between centroids

Hello with candidate version 1.15, linux64, X11 I want to measure the distance between the centroids of two aromatic stacking rings. The usual way of measuring distances does not work (clicking as needed has no effect), contrary to what the manual says. And I should have done successfully that measurement in the past. Also between one of the centroids and a regular atom: same issue. Distance between regular atoms works correctly. thanks for advice francesco pietra