My mistake, stderr *is* getting a constant repeat of these error messages in version 1.8.20-1ubuntu1 , I didn't wait long enough. The same six warning messages, every 60-120 seconds.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager-applet in Ubuntu. https://bugs.launchpad.net/bugs/1799213 Title: Gtk-CRITICAL gtk_widget_destroy: assertion 'GTK_IS_WIDGET (widget)' failed Status in network-manager-applet package in Ubuntu: Incomplete Bug description: Ubuntu 18.10, network-manager-gnome 1.8.18-2 Every three minutes or less, the applet writes to stderr these messages: (nm-applet:3677): Gtk-CRITICAL **: 08:09:47.640: gtk_widget_destroy: assertion 'GTK_IS_WIDGET (widget)' failed (nm-applet:3677): Gtk-CRITICAL **: 08:09:47.640: gtk_widget_destroy: assertion 'GTK_IS_WIDGET (widget)' failed (nm-applet:3677): Gtk-WARNING **: 08:09:47.668: Can't set a parent on widget which has a parent (nm-applet:3677): Gtk-CRITICAL **: 08:10:50.616: gtk_widget_destroy: assertion 'GTK_IS_WIDGET (widget)' failed (nm-applet:3677): Gtk-CRITICAL **: 08:10:50.616: gtk_widget_destroy: assertion 'GTK_IS_WIDGET (widget)' failed (nm-applet:3677): Gtk-WARNING **: 08:10:50.639: Can't set a parent on widget which has a parent Steps to reproduce: - install network-manager-gnome, add the nm-applet to the panel - wait Expected outcome: - not filling up error logs Seen outcome: - filling up error logs ProblemType: Bug DistroRelease: Ubuntu 18.10 Package: network-manager-gnome 1.8.18-2ubuntu2 ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12 Uname: Linux 4.18.0-10-generic x86_64 NonfreeKernelModules: nvidia_modeset nvidia ApportVersion: 2.20.10-0ubuntu13 Architecture: amd64 CurrentDesktop: XFCE Date: Mon Oct 22 08:08:37 2018 IfupdownConfig: # interfaces(5) file used by ifup(8) and ifdown(8) auto lo iface lo inet loopback InstallationDate: Installed on 2016-06-05 (869 days ago) InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) IpRoute: default via 192.168.1.1 dev enp5s0 proto dhcp metric 100 169.254.0.0/16 dev enp5s0 scope link metric 1000 192.168.1.0/24 dev enp5s0 proto kernel scope link src 192.168.1.111 metric 100 NetworkManager.state: [main] NetworkingEnabled=true WirelessEnabled=true WWANEnabled=false SourcePackage: network-manager-applet UpgradeStatus: Upgraded to cosmic on 2018-10-21 (0 days ago) modified.conffile..etc.default.apport: [modified] mtime.conffile..etc.default.apport: 2018-03-20T22:16:27.108498 nmcli-con: NAME UUID TYPE TIMESTAMP TIMESTAMP-REAL AUTOCONNECT AUTOCONNECT-PRIORITY READONLY DBUS-PATH ACTIVE DEVICE STATE ACTIVE-PATH SLAVE FILENAME Wired connection 1 ac8e86d9-6cff-3015-828a-e5fdbd9f5b0b ethernet 1540209985 Mon 22 Oct 2018 08:06:25 AM EDT yes -999 no /org/freedesktop/NetworkManager/Settings/1 yes enp5s0 activated /org/freedesktop/NetworkManager/ActiveConnection/1 -- /etc/NetworkManager/system-connections/Wired connection 1 nmcli-dev: DEVICE TYPE STATE DBUS-PATH CONNECTION CON-UUID CON-PATH enp5s0 ethernet connected /org/freedesktop/NetworkManager/Devices/2 Wired connection 1 ac8e86d9-6cff-3015-828a-e5fdbd9f5b0b /org/freedesktop/NetworkManager/ActiveConnection/1 wlp3s0 wifi disconnected /org/freedesktop/NetworkManager/Devices/3 -- -- -- lo loopback unmanaged /org/freedesktop/NetworkManager/Devices/1 -- -- -- nmcli-nm: RUNNING VERSION STATE STARTUP CONNECTIVITY NETWORKING WIFI-HW WIFI WWAN-HW WWAN running 1.12.4 connected started full enabled enabled enabled enabled disabled To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager-applet/+bug/1799213/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp