This bug was fixed in the package gnome-shell-extension-ubuntu-dock - 63ubuntu1.18.10.2
--------------- gnome-shell-extension-ubuntu-dock (63ubuntu1.18.10.2) cosmic; urgency=medium
[ Andrea Azzarone ] * theming: Ensure _trackingWindows contains valid windows (LP: #1769383)
-- Marco Trevisan (Treviño) <email address hidden> Tue, 15 Jan 2019 22:35:34 +0100
This bug was fixed in the package gnome-shell- extension- ubuntu- dock - 63ubuntu1.18.10.2
--------------- extension- ubuntu- dock (63ubuntu1.18.10.2) cosmic; urgency=medium
gnome-shell-
[ Andrea Azzarone ]
* theming: Ensure _trackingWindows contains valid windows (LP: #1769383)
-- Marco Trevisan (Treviño) <email address hidden> Tue, 15 Jan 2019 22:35:34 +0100