Maybe related to the following bug report for Xubuntu 17.10 from November 2017 ?
"Mouse acceleration/sensitivity adjustment has no effect" https://bugs.launchpad.net/ubuntu/+source/xfce4-settings/+bug/1729762
Since I don't use Xubuntu 17.10 however, I can't tell.
Maybe related to the following bug report for Xubuntu 17.10 from November 2017 ?
"Mouse acceleration/ sensitivity adjustment has no effect" /bugs.launchpad .net/ubuntu/ +source/ xfce4-settings/ +bug/1729762
https:/
Since I don't use Xubuntu 17.10 however, I can't tell.