I get the following error when I try to start gnome-control-center on Kubuntu 19.04:
$ gnome-control-center
(gnome-control-center:3239): Gtk-WARNING **: 16:12:56.364: Theme parsing error: gtk.css:68:35: The style property GtkButton:child-displacement-x is deprecated and shouldn't be used anymore. It will be removed in a future version
(gnome-control-center:3239): Gtk-WARNING **: 16:12:56.364: Theme parsing error: gtk.css:69:35: The style property GtkButton:child-displacement-y is deprecated and shouldn't be used anymore. It will be removed in a future version
**
ERROR:../shell/cc-shell-model.c:458:cc_shell_model_set_panel_visibility: assertion failed: (valid)
Aborted (core dumped)
Any idea on how to solve it?