Comment 13 for bug 1719244

apt-cache policy mate-panel

mate-panel:
  Installed: 1.20.1-3ubuntu1
  Candidate: 1.20.1-3ubuntu1
  Version table:
 *** 1.20.1-3ubuntu1 500
        500 http://gb.archive.ubuntu.com/ubuntu bionic/universe amd64 Packages
        100 /var/lib/dpkg/status