I've managed to disable mouse acceleration in 17.04 with the following command:
xinput --set-prop 8 'libinput Accel Profile Enabled' 0, 1
However! As soon as I restart the computer, the setting is no longer in effect. How do I make it permanent?
Solved by adding the line at the end of ~/.profile
Open a terminal (ctrl+alt+t)
Use your text editor of choice to edit '~/.profile'
$ nano ~/.profile
Add the following line at the bottom of the text file.
xinput --set-prop 8 'libinput Accel Profile Enabled' 0, 1
8 is the id of the mouse I want the settings applied to. In your case, this number can be something else. You can list your devices with xinput -list to figure out what yours is.
Save the changes, and the command should be executed every time you log on to your desktop.