Permissions on mesh desktop notifications

src/zeronetavahi

@@ -132,7 +132,7 @@ function detect_new_tox_users {
                     # get the nick of the user
                     toxuser="$(echo "$line" | awk -F ' ' '{print $1}')"
 
-                    notify-send $"$toxuser" $"has joined the mesh" --icon=dialog-information
+                    export DISPLAY=:0.0 && export XAUTHORITY=/home/$MESH_USERNAME/.Xauthority && sudo -u MESH_USERNAME /usr/bin/notify-send $"$toxuser" $"has joined the mesh" --icon=dialog-information
                 fi
             fi
         done < "$CURRENT_USERS_FILE"