Comment 5 for bug 1024482

Just to add and clarify, this is not a lightdm issue. Your DE should be theming the root window cursor theme, not the DM.

I think you will find this does not occur in KDE as it is setting the theme when the KDE session is started, and with Gnome, I am guessing the theme is set with GDM hence why the issue occurs in Gnome with lightdm and not GDM.

Xfce being a lighter DE and usually started with GDM (prior to Gnome3), Xfce left the root window cursor theming to GDM.

So for setups outside of the above, you need you set the default cursor theme yourself as I described in the previous post.

So, to be clear, root window cursor theming is the job of the DE, not the DM. When using tools outside of the DE defaults, expect some things to not work as expected as the "3rd party" tools do not have the same integration as the DE defaults do.

Cheers.