I’ve just updated my system for a spot of fun from 15.10 Vivid Vervet to 16.04 Xenial Xerus which is in Development at the moment. The upgrade went smoothly although it took a long time. I upgraded using:
sudo do-release-upgrade -d
This forces the release-upgrade tool to look for a suitable development version.
After the upgrade completed and I rebooted into the cinnamon desktop I was faced with the same problem I experienced when I installed Cinnamon Desktop on my Kubuntu 15.10 installation. That was every time I logged into my session a blank Abiword document opened. It turns out that this is due to a problem in an Abiword collaboration plugin in telepathy.
The way to fix this without removing Abiword is to remove the file /usr/share/dbus-1/services/org.freedesktop.Telepathy.Client.AbiCollab.service. To do this you must delete this as a superuser so type or paste the following into a terminal:
sudo rm /usr/share/dbus-1/services/org.freedesktop.Telepathy.Client.AbiCollab.service
The bug details and solution can be seen at https://bugs.launchpad.net/ubuntu/+source/abiword/+bug/1432271
I hope this helps it’s concerning that it is now in two versions. I hope this gets solved before the final release of 16.04 on the 21st of April next year.
This bug also affects older versions of Ubuntu too. I discovered this on my 15.10 desktop too.