Comment 108 for bug 1335492

Thanks Yanpas, your remark helped me a lot! Viewing the thread on https://bugzilla.xfce.org/show_bug.cgi?id=11266 I found the remark that led to a solution that seems to work for me.

As suggested there I:
- added the PPA (sudo add-apt-repository ppa:xubuntu-dev/xfce-4.12)
- sudo apt-get update
- Opened up Synaptic and searched for xfdesktop
- Marked xfdesktop for update (dependencies selected automatically) and clicked APPLY
- As a result, Synaptic updated xfdesktop to version 4.12.2
- Exit Synaptic
- Removed Xubuntu Developers ppa ((sudo add-apt-repository --remove ppa:xubuntu-dev/xfce-4.12) to keep everything else as a "stable" version.

Did this on multiple boxes (32 and 64 bit) and it seems to solve the problem!

Thanks to all developers for solving this annoying bug!