This bug happened to me a number of times as well, on a fresh install of Ubuntu 18.04.1 on a Clevo W230ST (Intel Haswell, nvidia Optimus); it never happened after a lock screen but only after a suspend/resume; the nvidia proprietary drivers 396 are installed but not loaded, as I am using the Intel integrated graphics; the nouveau module is blacklisted. I attach the relevant syslog.
** Attachment added: "logfile" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1785964/+attachment/5191335/+files/log.txt -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1785964 Title: Unable to unlock the desktop session: systemd-logind: got pause for 13:69 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1785964/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp