JS ERROR: TypeError: this._workspaceIsolation is undefined

[Jerry Quinn]

From syslog:

Apr 4 01:04:02 cerberus gnome-shell[4263]: JS ERROR: TypeError: monitor is null#012_reposition@resource:///org/gnome/shell/ui/boxpointer.js:508:13#012wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22#012_allocate@resource:///org/gnome/shell/ui/boxpointer.js:235:13#012wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22#012_init/<@resource:///org/gnome/shell/ui/layout.js:210:17#012_updateRegions@resource:///org/gnome/shell/ui/layout.js:989:9#012wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
Apr 4 01:04:02 cerberus gnome-shell[4263]: JS WARNING: [/<email address hidden>/docking.js 1778]: reference to undefined property "_workspaceIsolation"
Apr 4 01:04:02 cerberus gnome-shell[4263]: JS ERROR: TypeError: this._workspaceIsolation is undefined#012DockManager<._deleteDocks@/<email address hidden>/docking.js:1778:9#012wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22#012DockManager<._toggle@/<email address hidden>/docking.js:1662:9#012wrapper@resource:///org/gnome/gjs/modules/_legacy.js:82:22
Apr 4 01:04:02 cerberus gnome-shell[4263]: [AppIndicatorSupport-DEBUG] Registering StatusNotifierItem :1.70/org/ayatana/NotificationItem/classicmenu_indicator
Apr 4 01:04:02 cerberus gnome-shell[4263]: [AppIndicatorSupport-DEBUG] Registering StatusNotifierItem :1.105/org/ayatana/NotificationItem/software_update_available
Apr 4 01:04:02 cerberus gnome-shell[4263]: [AppIndicatorSupport-DEBUG] Registering StatusNotifierItem :1.105/org/ayatana/NotificationItem/livepatch
Apr 4 01:04:02 cerberus gnome-shell[4263]: [AppIndicatorSupport-DEBUG] Registering StatusNotifierItem :1.69/org/ayatana/NotificationItem/org_gnome_Pomodoro

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gnome-shell 3.28.4-0ubuntu18.04.3
ProcVersionSignature: Ubuntu 4.15.0-94.95-generic 4.15.18
Uname: Linux 4.15.0-94-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.14
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sat Apr 4 01:10:22 2020
DisplayManager: gdm3
GsettingsChanges:
 b'org.gnome.shell' b'enabled-extensions' b"['<email address hidden>', '<email address hidden>', '<email address hidden>', '<email address hidden>']"
 b'org.gnome.shell' b'command-history' redacted by apport
 b'org.gnome.shell' b'favorite-apps' redacted by apport
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
 b'org.gnome.desktop.interface' b'clock-show-date' b'true'
InstallationDate: Installed on 2016-05-30 (1404 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to bionic on 2018-09-17 (565 days ago)