Comment 3 for bug 1599599

Also, I think/hope this is the version of the package:

linux-image-extra-4.4.0-28-generic:
  Installed: 4.4.0-28.47
  Candidate: 4.4.0-28.47
  Version table:
 *** 4.4.0-28.47 500
        500 http://ca.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages
        100 /var/lib/dpkg/status