I got it to work, and it fixes my problem with the launcher resulting in an unknown file error on /usr/bin/compiz.
Go to Software & Updates via command line ubuntu-software & and selecting it from a list of apt applications.
Use Developer Options to enable xenial-proposed.
Then run command line: sudo apt-get install libgl1-mesa-dri/xenial-proposed
This installed it for me.
I got it to work, and it fixes my problem with the launcher resulting in an unknown file error on /usr/bin/compiz.
Go to Software & Updates via command line
ubuntu-software &
and selecting it from a list of apt applications.
Use Developer Options to enable xenial-proposed.
Then run command line: mesa-dri/ xenial- proposed
sudo apt-get install libgl1-
This installed it for me.