After I installed qtcreator-plugin-ubuntu (3.5.0+16.04.20160419-0ubuntu1) on ubuntu mate 16.04 LTS 64 bit, the mate desktop stopped loading. I could login using lightdm but lightdm background never went away.
If I switched to a terminal and logged in there, I could run startx and get desktop back.
When I uninstalled qtcreator-plugin-ubuntu and autoremoved its many dependencies, login to desktop worked fine.
Happened on two ubuntu mate 16.04 LTS 64bit installations.
Using
mate-desktop 1.12.1-1
mate-desktop-environment-core 1.12.0+1
Should I report this as a bug?