This bug was fixed in the package ubuntu-mate-artwork - 16.10.6
--------------- ubuntu-mate-artwork (16.10.6) yakkety; urgency=medium
* Update Ubuntu MATE themes to support GTK 3.20. (LP: #1593048)
-- Martin Wimpress <email address hidden> Wed, 17 Aug 2016 13:10:02 +0100
This bug was fixed in the package ubuntu-mate-artwork - 16.10.6
---------------
ubuntu-mate-artwork (16.10.6) yakkety; urgency=medium
* Update Ubuntu MATE themes to support GTK 3.20. (LP: #1593048)
-- Martin Wimpress <email address hidden> Wed, 17 Aug 2016 13:10:02 +0100