The Mypaint developper Andrew Chadwick just created a ppa for Mypaint-testing.
Ppa URL : https://launchpad.net/~achadwick/+archive/mypaint-testing
This mean you ( Ubuntu or Ubuntu based distribution user ) can now follow Mypaint bleeding edge stuff or help playtest with only 3 line to paste in your terminal :
sudo add-apt-repository ppa:achadwick/mypaint-testing sudo apt-get update sudo apt-get install mypaint
Don't forget to also help developpers making Mypaint better with your bug reports and feedbacks : https://gna.org/bugs/?group=mypaint. Thanks !
( PS: If like me you compiled the master branch before and installed it to /usr/local/ you probably need to uninstall your previous Mypaint installation... I personally did it manually by deleting /usr/local/bin/mypaint and /usr/local/share/mypaint to keep things clean )