Here's the installation log from the day the regression happened (I think).

Start-Date: 2018-04-19  09:16:47
Commandline: apt full-upgrade
Requested-By: dan (1000)
Install: libisc169:amd64 (1:9.11.3+dfsg-1ubuntu1, automatic), libisc-export169:amd64 (1:9.11.3+dfsg-1ubuntu1, automatic), libsysmetrics1:amd64 (1.0.8, automatic), libdns-export1100:amd64 (1:9.11.3+dfsg-1ubuntu1, automatic), gnome-initial-setup:amd64 (3.28.0-2ubuntu3, automatic), libdns1100:amd64 (1:9.11.3+dfsg-1ubuntu1, automatic), ubuntu-report:amd64 (1.0.8, automatic)
Upgrade: ubuntu-settings:amd64 (18.04.4, 18.04.5), libgoa-backend-1.0-1:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), libgjs-dev:amd64 (1.52.1-1, 1.52.1-1ubuntu1), gnome-calendar:amd64 (3.28.1-1ubuntu1, 3.28.1-1ubuntu2), netplan.io:amd64 (0.34.1, 0.35), libibus-1.0-dev:amd64 (1.5.17-3ubuntu3, 1.5.17-3ubuntu4), libisccfg160:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), networkd-dispatcher:amd64 (1.7-0ubuntu1, 1.7-0ubuntu2), gir1.2-mutter-2:amd64 (3.28.0-2, 3.28.1-1), libgoa-1.0-0b:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), update-notifier-common:amd64 (3.190, 3.191), libgoa-1.0-common:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), libgjs0g:amd64 (1.52.1-1, 1.52.1-1ubuntu1), libirs160:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), bind9-host:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), dnsutils:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), ubuntu-standard:amd64 (1.416, 1.417), ubuntu-desktop:amd64 (1.416, 1.417), libmutter-2-0:amd64 (3.28.0-2, 3.28.1-1), libgoa-1.0-dev:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), gjs:amd64 (1.52.1-1, 1.52.1-1ubuntu1), libkeyutils-dev:amd64 (1.5.9-9.2ubuntu1, 1.5.9-9.2ubuntu2), isc-dhcp-common:amd64 (4.3.5-3ubuntu6, 4.3.5-3ubuntu7), command-not-found-data:amd64 (18.04.2, 18.04.3), gnumeric-doc:amd64 (1.12.35-1, 1.12.35-1.1), ibus-gtk:amd64 (1.5.17-3ubuntu3, 1.5.17-3ubuntu4), ibus-gtk3:amd64 (1.5.17-3ubuntu3, 1.5.17-3ubuntu4), gnumeric-common:amd64 (1.12.35-1, 1.12.35-1.1), mutter-common:amd64 (3.28.0-2, 3.28.1-1), nplan:amd64 (0.34.1, 0.35), ubuntu-minimal:amd64 (1.416, 1.417), python3-distupgrade:amd64 (1:18.04.16, 1:18.04.17), python3-commandnotfound:amd64 (18.04.2, 18.04.3), ubuntu-release-upgrader-core:amd64 (1:18.04.16, 1:18.04.17), libgoa-backend-1.0-dev:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), liblwres160:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), libkeyutils1:amd64 (1.5.9-9.2ubuntu1, 1.5.9-9.2ubuntu2), gnome-shell-common:amd64 (3.28.0-0ubuntu5, 3.28.1-0ubuntu1), gir1.2-goa-1.0:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), gnome-online-accounts:amd64 (3.28.0-0ubuntu1, 3.28.0-0ubuntu2), ibus:amd64 (1.5.17-3ubuntu3, 1.5.17-3ubuntu4), thermald:amd64 (1.7.0-3, 1.7.0-5), ubuntu-release-upgrader-gtk:amd64 (1:18.04.16, 1:18.04.17), mythes-en-us:amd64 (1:6.0.3-2, 1:6.0.3-3), libibus-1.0-5:amd64 (1.5.17-3ubuntu3, 1.5.17-3ubuntu4), gir1.2-ibus-1.0:amd64 (1.5.17-3ubuntu3, 1.5.17-3ubuntu4), command-not-found:amd64 (18.04.2, 18.04.3), libisccc160:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), gnome-shell:amd64 (3.28.0-0ubuntu5, 3.28.1-0ubuntu1), libbind9-160:amd64 (1:9.11.2.P1-1ubuntu5, 1:9.11.3+dfsg-1ubuntu1), ubuntu-web-launchers:amd64 (18.04.4, 18.04.5), gnumeric:amd64 (1.12.35-1, 1.12.35-1.1), libmutter-2-dev:amd64 (3.28.0-2, 3.28.1-1), isc-dhcp-client:amd64 (4.3.5-3ubuntu6, 4.3.5-3ubuntu7), update-notifier:amd64 (3.190, 3.191), mutter:amd64 (3.28.0-2, 3.28.1-1)
Remove: gnome-shell-dbgsym:amd64 (3.28.0-0ubuntu5), libmutter-2-0-dbgsym:amd64 (3.28.0-2), mutter-dbgsym:amd64 (3.28.0-2)
End-Date: 2018-04-19  09:17:30

Start-Date: 2018-04-19  09:17:59
Commandline: apt autoremove
Requested-By: dan (1000)
Remove: libdns-export169:amd64 (1:9.11.2.P1-1ubuntu5), libisc166:amd64 (1:9.11.2.P1-1ubuntu5), libisc-export166:amd64 (1:9.11.2.P1-1ubuntu5), libdns169:amd64 (1:9.11.2.P1-1ubuntu5)
End-Date: 2018-04-19  09:18:00