Testing the ppa:kubuntu-ppa/backports-landing. Muon broke after the update. I suspected it was related to the issue discover notifier issue, but now that the notifier issue is fixed, the Muon install issue remains. Confirmed on 2 different machines upgraded from 15.10. Message from sudo apt install muon: muon : Depends: libmuon (= 4:5.4.3-0ubuntu1~ubuntu15.10~ppa1) but it is not going to be installed. E: Unable to correct problems, you have held broken packages. However, sudo dpkg --configure -a, along with autoremove and clean did not fix the issue. Current active sources from /etc/apt/sources.list: deb http://us.archive.ubuntu.com/ubuntu/ wily main restricted deb-src http://us.archive.ubuntu.com/ubuntu/ wily main restricted deb-src http://us.archive.ubuntu.com/ubuntu/ wily-updates main restricted deb http://us.archive.ubuntu.com/ubuntu/ wily-updates main restricted deb http://us.archive.ubuntu.com/ubuntu/ wily multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ wily multiverse deb http://us.archive.ubuntu.com/ubuntu/ wily-updates multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ wily-updates multiverse deb http://us.archive.ubuntu.com/ubuntu/ wily-backports main restricted universe multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ wily-backports main restricted universe multiverse deb http://security.ubuntu.com/ubuntu wily-security main restricted deb-src http://security.ubuntu.com/ubuntu wily-security main restricted deb http://security.ubuntu.com/ubuntu wily-security universe deb-src http://security.ubuntu.com/ubuntu wily-security universe deb http://security.ubuntu.com/ubuntu wily-security multiverse deb-src http://security.ubuntu.com/ubuntu wily-security multiverse
What can we do to help? This should be reported downstream to the repository owners.