(lightdm-gtk-greeter:2401): Gtk-CRITICAL **: gtk_container_foreach: assertion 'GTK_IS_CONTAINER (container)' failed

(lightdm-gtk-greeter:2401): Gtk-CRITICAL **: gtk_container_foreach: assertion 'GTK_IS_CONTAINER (container)' failed

(lightdm-gtk-greeter:2401): Gtk-CRITICAL **: gtk_container_foreach: assertion 'GTK_IS_CONTAINER (container)' failed

** (lightdm-gtk-greeter:2401): WARNING **: Failed to load user background: Impossible d'ouvrir le fichier « /home/phoenix/Dropbox/IMG_0792.jpg » : Permission non accordée