On Xubuntu, can you try downgrading the package xubuntu-default-settings from version 18.04.2 to version 18.04.1? Maybe it's related to what I'm seeing in bug #1752798
(you can find the older package here: https://launchpad.net/ubuntu/+source/xubuntu-default-settings/18.04.1/+build/13749132 )
On Xubuntu, can you try downgrading the package xubuntu- default- settings from version 18.04.2 to version 18.04.1? Maybe it's related to what I'm seeing in bug #1752798
(you can find the older package here: https:/ /launchpad. net/ubuntu/ +source/ xubuntu- default- settings/ 18.04.1/ +build/ 13749132 )