Strange syslog data after late-night system freeze

While running a batch dig-x script, my Lenovo T420 laptop running Etiona froze. Upon restart in
the morning, there was next to nothing recorded in /var/log/syslog:
Starting with the last of the frozen session's log:
... Oct 22 20:02:37 george-ThinkPad-T420 systemd[1]: Started Run anacron jobs.
Oct 22 20:02:37 george-ThinkPad-T420 anacron[7851]: Anacron 2.3 started on 2021-10-22
Oct 22 20:02:37 george-ThinkPad-T420 anacron[7851]: Normal exit (0 jobs run)
Oct 22 20:17:01 george-ThinkPad-T420 CRON[7939]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Oct 22 20:32:00 george-ThinkPad-T420 wpa_supplicant[830]: [redacted]: WPA: Group rekeying completed with [redacted] [GTK=CCMP]
Oct 22 20:32:16 george-ThinkPad-T420 mate-screensaver-dialog: pam_ecryptfs: seteuid error
Oct 22 20:57:56 george-ThinkPad-T420 dbus-daemon[823]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service' requested by ':1.776' (uid=1000 pid=8109 comm="/usr/lib/abrowser/abrowser " label="unconfined")
Oct 22 20:57:56 george-ThinkPad-T420 systemd[1]: Starting Hostname Service...
Oct 22 20:57:56 george-ThinkPad-T420 dbus-daemon[823]: [system] Successfully activated service 'org.freedesktop.hostname1'
Oct 22 20:57:56 george-ThinkPad-T420 systemd[1]: Started Hostname Service.
Oct 22 20:59:17 george-ThinkPad-T420 dbus-daemon[823]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service' requested by ':1.781' (uid=1000 pid=8109 comm="/usr/lib/abrowser/abrowser " label="unconfined")
Oct 22 20:59:17 george-ThinkPad-T420 systemd[1]: Starting Hostname Service...
Oct 22 20:59:18 george-ThinkPad-T420 dbus-daemon[823]: [system] Successfully activated service 'org.freedesktop.hostname1'
Oct 22 20:59:18 george-ThinkPad-T420 systemd[1]: Started Hostname Service.
Oct 22 21:01:04 george-ThinkPad-T420 dbus-daemon[823]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service' requested by ':1.796' (uid=1000 pid=8109 comm="/usr/lib/abrowser/abrowser " label="unconfined")
Oct 22 21:01:04 george-ThinkPad-T420 systemd[1]: Starting Hostname Service...
Oct 22 21:01:04 george-ThinkPad-T420 dbus-daemon[823]: [system] Successfully activated service 'org.freedesktop.hostname1'
Oct 22 21:01:04 george-ThinkPad-T420 systemd[1]: Started Hostname Service.
Oct 22 21:01:26 george-ThinkPad-T420 systemd[1]: Started Run anacron jobs.
Oct 22 21:01:26 george-ThinkPad-T420 anacron[8742]: Anacron 2.3 started on 2021-10-22
Oct 22 21:01:26 george-ThinkPad-T420 anacron[8742]: Normal exit (0 jobs run)
Oct 22 21:01:42 george-ThinkPad-T420 dbus-daemon[823]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service' requested by ':1.799' (uid=1000 pid=8109 comm="/usr/lib/abrowser/abrowser " label="unconfined")
Oct 22 21:01:42 george-ThinkPad-T420 systemd[1]: Starting Hostname Service...
Oct 22 21:01:43 george-ThinkPad-T420 dbus-daemon[823]: [system] Successfully activated service 'org.freedesktop.hostname1'
Oct 22 21:01:43 george-ThinkPad-T420 systemd[1]: Started Hostname Service.
Oct 22 21:06:58 george-ThinkPad-T420 systemd[1]: Starting Daily apt download activities...
Oct 22 21:06:59 george-ThinkPad-T420 systemd[1]: Started Daily apt download activities.
Oct 22 21:17:01 george-ThinkPad-T420 CRON[8929]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Oct 22 21:32:00 george-ThinkPad-T420 wpa_supplicant[830]: [redacted]: WPA: Group rekeying completed with [redacted] [GTK=CCMP]

Several peculiarities appear in the above syslog:
wpa_supplicant[830]: [redacted]: WPA: Group rekeying completed with [redacted] [GTK=CCMP] <== repeated 11 times.<== Nine times in today's normal startup log.
dbus-daemon[823]: [system] Activating via systemd: ... <== repeated ten times, in pairs with the line below: | Hostname =
dbus-daemon[823]: [system] Successfully activated service ... <== repeated ten times, in pairs with the above: | org.freedesktop.hostname1 <== Just three times today.
notify-osd[3442]: dnd_is_screensaver_active(): Got error "The name org.gnome.ScreenSaver was not provided by any .service files" <== repeated four times.<== None today.
systemd-resolved[800]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP. <== repeated four times.<== just twice today.

Continuing with all of the following morning's startup log:
Oct 23 08:07:38 george-ThinkPad-T420 rsyslogd: [origin software="rsyslogd" swVersion="8.32.0" x-pid="799" x-info="http://www.rsyslog.com"] rsyslogd was HUPed
Oct 23 08:07:38 george-ThinkPad-T420 anacron[795]: Job `cron.daily' terminated
Oct 23 08:07:38 george-ThinkPad-T420 anacron[795]: Normal exit (1 job run)
Oct 23 08:09:49 george-ThinkPad-T420 gvfsd-metadata[1410]: g_udev_device_has_property: assertion 'G_UDEV_IS_DEVICE (device)' failed