Lubuntu to Ubuntu

I recently needed to change a machine from Lubuntu to Ubuntu after a test installation. The main thing was:

sudo apt-get install ubuntu-desktop

But that left the log-in looking wrong. I tried:

sudo dpkg-reconfigure lightdm

… but that didn’t work (at least, not on its own). The solution was to change the greeter-session from lightdm-gtk-greeter to unity-greeter. See:

Lightdm autologin problem on Lubuntu 12.10

And being fussy I also wanted to change the default splashscreen to Ubuntu:

Change the boot splash screen theme in Ubuntu/Lubuntu 12.10