I partially reproduced the issue in 42.3. First I successfully hibernated by using the action buttons. On recover, then I intentionally logged in console as root, tried to hibernate again and it failed with no prompts or messages (desktop computer). <30>1 2018-03-01T13:55:40.458562+01:00 Telcontar xinetd 2312 - - START: nntp from=127.0.0.1 <30>1 2018-03-01T13:55:40.458915+01:00 Telcontar xinetd 2312 - - START: nntp from=127.0.0.1 <86>1 2018-03-01T13:55:40.720430+01:00 Telcontar login - - - pam_unix(login:session): session opened for user root by LOGIN(uid=0) <30>1 2018-03-01T13:55:40.742800+01:00 Telcontar systemd 1 - - Created slice User Slice of root. <30>1 2018-03-01T13:55:40.778105+01:00 Telcontar systemd 1 - - Starting User Manager for UID 0... <30>1 2018-03-01T13:55:40.780826+01:00 Telcontar systemd 1 - - Started Session 1235 of user root. <38>1 2018-03-01T13:55:40.781388+01:00 Telcontar systemd-logind 1753 - - New session 1235 of user root. <86>1 2018-03-01T13:55:40.789160+01:00 Telcontar systemd - - - pam_unix(systemd-user:session): session opened for user root by (uid=0) <30>1 2018-03-01T13:55:40.867403+01:00 Telcontar systemd 1 - - Started User Manager for UID 0. <30>1 2018-03-01T13:55:40.930737+01:00 Telcontar console-kit-daemon 5074 - - (process:22717): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed <85>1 2018-03-01T13:55:40.947803+01:00 Telcontar login - - - ROOT LOGIN ON tty1 Logged as root in console, then ctrl-alt-f7 <30>1 2018-03-01T13:55:41.515839+01:00 Telcontar xinetd 2312 - - EXIT: nntp status=0 duration=914(sec) <30>1 2018-03-01T13:55:41.533116+01:00 Telcontar xinetd 2312 - - EXIT: nntp status=0 duration=914(sec) <30>1 2018-03-01T13:55:42.959235+01:00 Telcontar console-kit-daemon 5074 - - (process:22774): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed <86>1 2018-03-01T13:56:01.232952+01:00 Telcontar cron 22824 - - pam_unix(crond:session): session opened for user news by (uid=0) <30>1 2018-03-01T13:56:01.259186+01:00 Telcontar systemd 1 - - Created slice User Slice of news. <30>1 2018-03-01T13:56:01.314026+01:00 Telcontar systemd 1 - - Starting User Manager for UID 9... <30>1 2018-03-01T13:56:01.316793+01:00 Telcontar systemd 1 - - Started Session 1236 of user news. <86>1 2018-03-01T13:56:01.318738+01:00 Telcontar systemd - - - pam_unix(systemd-user:session): session opened for user news by (uid=0) <30>1 2018-03-01T13:56:01.424978+01:00 Telcontar systemd 1 - - Started User Manager for UID 9. <86>1 2018-03-01T13:56:14.282389+01:00 Telcontar CRON 22824 - - pam_unix(crond:session): session closed for user news <30>1 2018-03-01T13:56:16.741122+01:00 Telcontar systemd 1 - - Stopping User Manager for UID 9... <86>1 2018-03-01T13:56:16.787246+01:00 Telcontar systemd - - - pam_unix(systemd-user:session): session closed for user news <30>1 2018-03-01T13:56:16.787897+01:00 Telcontar systemd 1 - - Stopped User Manager for UID 9. <30>1 2018-03-01T13:56:16.788877+01:00 Telcontar systemd 1 - - Removed slice User Slice of news. Request hibernation from action buttons <28>1 2018-03-01T13:56:29.532249+01:00 Telcontar systemd-sleep 21829 - - system-sleep terminated by signal ALRM. <30>1 2018-03-01T13:56:29.535824+01:00 Telcontar systemd 1 - - Started Hibernate. <30>1 2018-03-01T13:56:29.536033+01:00 Telcontar systemd 1 - - sleep.target: Unit not needed anymore. Stopping. <30>1 2018-03-01T13:56:29.536207+01:00 Telcontar systemd 1 - - Stopped target Sleep. <30>1 2018-03-01T13:56:29.536376+01:00 Telcontar systemd 1 - - Reached target Hibernate. <38>1 2018-03-01T13:56:29.537128+01:00 Telcontar systemd-logind 1753 - - Operation 'sleep' finished. <30>1 2018-03-01T13:56:29.537715+01:00 Telcontar systemd 1 - - hibernate.target: Unit is bound to inactive unit systemd-hibernate.service. Stopping, too. <30>1 2018-03-01T13:56:29.537895+01:00 Telcontar systemd 1 - - Stopped target Hibernate. <86>1 2018-03-01T13:56:36.665811+01:00 Telcontar unix2_chkpwd - - - gkr-pam: unlocked login keyring <22>1 2018-03-01T13:57:33.311035+01:00 Telcontar dovecot - - - imap-login: Login: user=<cer>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, mpid=23019, TLS, session=<3ws2Z1lm5qJ/AAAB> <86>1 2018-03-01T14:00:01.288602+01:00 Telcontar cron 23313 - - pam_unix(crond:session): session opened for user root by (uid=0) After a while with blank screen, I enter password on screensaver. I see no prompt or message saying why hibernation failed. Instead, I routinely hibernate by command line as root, to avoid such XFCE problems: #!/bin/bash date --rfc-3339=seconds systemctl hibernate sleep 3 xscreensaver-command -lock