Even though Debian Jessie is to the point where it is not complaining about dependencies, things are not working properly.  Start-up scripts are not functioning properly or randomly exploding.  The NetworkManager doesn’t start, virtual interfaces aren’t getting initialized.  If I run the same commands by hand after it boots everything works, so something is wrong with the startup.

     In addition the graphical greeter just gives me “Oops something went terribly wrong”.  I’m used to seeing this if I have gdm3 badly configured but I can’t find anything obviously wrong, and even removing and reinstalling gdm3, Xorg, Mate, anything I can think that is related, doesn’t fix it.

     I ran into this problem trying to upgrade Mint as well, and the eventual fix was just to do a fresh install.

     I am initiating a fresh install on Debian now as well.  Odd, I’ve upgraded Ubuntu in place successfully on three different boxes, but it seems to be the only Debian based distribution where this really works properly.