Public bug reported: The official documentation for 16.04 is incomplete. It's the page with the title "Add additional software repositories". I believe that for non-Canonical repositories (but not PPAs) the user has to add the repository's key. Without the key the command "sudo apt-get update" will give an error message and packages cannot be added from the repository. As an example, see the link below for the instructions for adding the Play Deb 2 repository to 16.04.
http://www.playdeb.net/updates/Ubuntu/16.04 If my bug is correct then the documentation needs to be corrected. ** Affects: ubuntu Importance: Undecided Status: New ** Tags: documentation -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1612631 Title: Incomplete documentation: adding additional repositories To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1612631/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs