My guess would be that xfce4-power-manager still tries to hibernate the system, but that operation is not permitted. What do the following two commands return?
$ xfce4-power-manager --dump $ xfconf-query -c xfce4-power-manager -lv ** No longer affects: xubuntu-default-settings (Ubuntu) -- You received this bug notification because you are a member of Xubuntu Developers, which is subscribed to xubuntu-default-settings in Ubuntu. Matching subscriptions: xubuntu-default-settings https://bugs.launchpad.net/bugs/1768038 Title: Inactivity sleep mode on battery fails To manage notifications about this bug go to: https://bugs.launchpad.net/xfce4-power-manager/+bug/1768038/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~xubuntu-dev Post to : xubuntu-dev@lists.launchpad.net Unsubscribe : https://launchpad.net/~xubuntu-dev More help : https://help.launchpad.net/ListHelp