I experience very similar situation. 1. I have only one active Gnome Shell extension: "Disable Gestures" which gives me a desirable feature - to disable all multi-finger touch screen gestures. I just disabled it to see if that will resolve the issue. 2. Indeed, I found that sometimes clicking on app windows is affected, but the shell panel - not. 3. I have not tried Xorg sessions while this occurs. I will on next occasion. $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 18.04.1 LTS Release: 18.04 Codename: bionic $ uname -a Linux teabreak-3 4.15.0-33-generic #36-Ubuntu SMP Wed Aug 15 16:00:05 UTC 2018 x86_64 x86_64 x86_64 GNU/Linu From /var/log/syslog: Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #1 0x564764c1e828 i resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fba380b5de0 @ 71) Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #2 0x564764c1e7a8 i resource:///org/gnome/shell/ui/components/polkitAgent.js:342 (0x7fb9f2e6c340 @ 59) Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #3 0x564764c1e700 i resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fba380b5de0 @ 71) Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #4 0x564764c1e640 i self-hosted:916 (0x7fba380f12b8 @ 367) Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: == Stack trace for context 0x564764791330 == Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #0 0x564764c1e7a8 i resource:///org/gnome/shell/ui/components/polkitAgent.js:343 (0x7fb9f2e6c340 @ 84) Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #1 0x564764c1e700 i resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fba380b5de0 @ 71) Aug 30 17:53:31 ubuntu18 org.gnome.Shell.desktop[1166]: #2 0x564764c1e640 i self-hosted:916 (0x7fba380f12b8 @ 367) Aug 30 17:53:31 ubuntu18 gnome-shell[1166]: Object St.Bin (0x5647680732a0), has been already deallocated - impossible to access to it. This might be caused by the fact that the object has been destroyed from C code using something such as destroy(), dispose(), or remove() vfuncs Aug 30 17:53:31 ubuntu18 gnome-shell[1166]: Object St.Bin (0x5647680732a0), has been already deallocated - impossible to access to it. This might be caused by the fact that the object has been destroyed from C code using something such as destroy(), dispose(), or remove() vfuncs Aug 30 17:54:40 ubuntu18 vnstatd[894]: Error: Unable to create database backup "/var/lib/vnstat/.enp2s0". Aug 30 17:54:40 ubuntu18 vnstatd[894]: Error: Unable to create database backup "/var/lib/vnstat/.wlx503eaa5fe4b0". Aug 30 17:59:40 ubuntu18 vnstatd[894]: Error: Unable to create database backup "/var/lib/vnstat/.enp2s0". Aug 30 17:59:40 ubuntu18 vnstatd[894]: Error: Unable to create database backup "/var/lib/vnstat/.wlx503eaa5fe4b0". Aug 30 17:59:47 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating service name='org.gnome.ControlCenter.SearchProvider' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating service name='org.gnome.Nautilus' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating service name='org.gnome.Calculator.SearchProvider' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating service name='org.gnome.Calendar' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating service name='org.gnome.Gnote' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating service name='org.gnome.seahorse.Application' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating via systemd: service name='org.gnome.Terminal' unit='gnome-terminal-server.service' requested by ':1.33' (uid=1000 pid=1166 comm="/usr/bin/gnome-shell " label="unconfined") Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.Calculator.SearchProvider' Aug 30 17:59:48 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.ControlCenter.SearchProvider' Aug 30 17:59:48 ubuntu18 systemd[955]: Starting GNOME Terminal Server... Aug 30 17:59:51 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.Terminal' Aug 30 17:59:51 ubuntu18 systemd[955]: Started GNOME Terminal Server. Aug 30 17:59:51 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.seahorse.Application' Aug 30 17:59:51 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.Gnote' Aug 30 17:59:51 ubuntu18 gnome-shell[1166]: Received error from DBus search provider gnote.desktop: Gio.DBusError: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface 'org.gnome.Shell.SearchProvider2' on object at path /org/gnome/Gnote/SearchProvider Aug 30 17:59:52 ubuntu18 gnome-shell[1166]: message repeated 2 times: [ Received error from DBus search provider gnote.desktop: Gio.DBusError: GDBus.Error:org.freedesktop.DBus.Error.UnknownMethod: No such interface 'org.gnome.Shell.SearchProvider2' on object at path /org/gnome/Gnote/SearchProvider] Aug 30 17:59:53 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Activating via systemd: service name='org.gtk.GLib.PACRunner' unit='glib-pacrunner.service' requested by ':1.105' (uid=1000 pid=16730 comm="gnome-calculator --solve gn " label="unconfined") Aug 30 17:59:53 ubuntu18 systemd[955]: Starting GLib proxy auto-configuration service... Aug 30 17:59:53 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gtk.GLib.PACRunner' Aug 30 17:59:53 ubuntu18 systemd[955]: Started GLib proxy auto-configuration service. Aug 30 17:59:55 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.Nautilus' Aug 30 17:59:59 ubuntu18 dbus-daemon[1016]: [session uid=1000 pid=1016] Successfully activated service 'org.gnome.Calendar' Aug 30 18:00:00 ubuntu18 nautilus[16701]: invalid uninstantiatable type '(null)' in cast to 'GObject' Aug 30 18:00:00 ubuntu18 nautilus[16701]: g_object_notify: assertion 'G_IS_OBJECT (object)' failed Aug 30 18:00:00 ubuntu18 nautilus[16701]: invalid uninstantiatable type '(null)' in cast to 'GObject' Aug 30 18:00:00 ubuntu18 nautilus[16701]: g_object_notify: assertion 'G_IS_OBJECT (object)' failed Aug 30 18:00:00 ubuntu18 nautilus[16701]: invalid unclassed pointer in cast to 'GObject' Aug 30 18:00:00 ubuntu18 nautilus[16701]: g_object_notify: assertion 'G_IS_OBJECT (object)' failed Aug 30 18:00:01 ubuntu18 CRON[17082]: (smmsp) CMD (test -x /etc/init.d/sendmail && test -x /usr/share/sendmail/sendmail && test -x /usr/lib/sm.bin/sendmail && /usr/share/sendmail/sendmail cron-msp) Aug 30 18:00:19 ubuntu18 dhclient[1020]: DHCPREQUEST of 192.168.1.119 on wlx503eaa5fe4b0 to 192.168.1.254 port 67 (xid=0x30a753f1) Aug 30 18:00:19 ubuntu18 dhclient[1020]: DHCPACK of 192.168.1.119 from 192.168.1.254 Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1719] dhcp4 (wlx503eaa5fe4b0): address 192.168.1.119 Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1720] dhcp4 (wlx503eaa5fe4b0): plen 24 (255.255.255.0) Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1720] dhcp4 (wlx503eaa5fe4b0): gateway 192.168.1.254 Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1720] dhcp4 (wlx503eaa5fe4b0): lease time 7200 Aug 30 18:00:19 ubuntu18 dbus-daemon[762]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service' requested by ':1.12' (uid=0 pid=775 comm="/usr/sbin/NetworkManager --no-daemon " label="unconfined") Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1720] dhcp4 (wlx503eaa5fe4b0): hostname 'ubuntu18' Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1720] dhcp4 (wlx503eaa5fe4b0): nameserver '192.168.1.254' Aug 30 18:00:19 ubuntu18 NetworkManager[775]: [1535623219.1720] dhcp4 (wlx503eaa5fe4b0): state changed bound -> bound Aug 30 18:00:19 ubuntu18 systemd[1]: Starting Network Manager Script Dispatcher Service... Aug 30 18:00:19 ubuntu18 dbus-daemon[762]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Aug 30 18:00:19 ubuntu18 systemd[1]: Started Network Manager Script Dispatcher Service. Aug 30 18:00:19 ubuntu18 nm-dispatcher: req:1 'dhcp4-change' [wlx503eaa5fe4b0]: new request (1 scripts) Aug 30 18:00:19 ubuntu18 nm-dispatcher: req:1 'dhcp4-change' [wlx503eaa5fe4b0]: start running ordered scripts... Aug 30 18:00:19 ubuntu18 dhclient[1020]: bound to 192.168.1.119 -- renewal in 2866 seconds. Aug 30 18:00:21 ubuntu18 gnome-shell[1166]: Received error from DBus search provider org.gnome.Software.desktop: Gio.IOErrorEnum: Timeout was reached Aug 30 18:00:24 ubuntu18 PackageKit: resolve transaction /2467_deddacaa from uid 1000 finished with success after 3597ms Aug 30 18:00:24 ubuntu18 gnome-software[1778]: State change on system/snap/Snap Store/desktop/gnome-calculator/* from available to installed is not OK Aug 30 18:00:31 ubuntu18 PackageKit: resolve transaction /2468_cbaaccda from uid 1000 finished with success after 522ms Aug 30 18:00:41 ubuntu18 org.gnome.Shell.desktop[1166]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x5c00007 (Shell Exte) Aug 30 18:01:01 ubuntu18 org.gnome.Shell.desktop[1166]: Window manager warning: Received a NET_CURRENT_DESKTOP message from a broken (outdated) client who sent a 0 timestamp Aug 30 18:01:01 ubuntu18 org.gnome.Shell.desktop[1166]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x4200001 (Slice & Gr) Aug 30 18:01:40 ubuntu18 gnome-shell[1166]: Object .Gjs_AppIndicatorIconActor__1 (0x564766bc4180), has been already finalized. Impossible to set any property to it. Aug 30 18:01:40 ubuntu18 org.gnome.Shell.desktop[1166]: == Stack trace for context 0x564764791330 == Aug 30 18:01:40 ubuntu18 org.gnome.Shell.desktop[1166]: #0 0x7ffc052944c0 I resource:///org/gnome/gjs/modules/_legacy.js:83 (0x7fba380b5de0 @ 87) Aug 30 18:01:40 ubuntu18 org.gnome.Shell.desktop[1166]: #1 0x564764c1ea78 i /