In attempting to add the sane-release repository, I got a 404 error and subsequently a "... disabled by default." message. Did I do something wrong?
$ sudo add-apt-repository https://launchpad.net/~sane-project/+archive/ubuntu/sane-release Hit:1 http://us.archive.ubuntu.com/ubuntu bionic InRelease Get:2 http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB] Get:3 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB] Ign:4 https://launchpad.net/~sane-project/+archive/ubuntu/sane-release bionic InRelease Err:5 https://launchpad.net/~sane-project/+archive/ubuntu/sane-release bionic Release 404 Not Found [IP: 91.189.89.222 443] Get:6 http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB] Get:7 http://security.ubuntu.com/ubuntu bionic-security/main amd64 DEP-11 Metadata [48.5 kB] Get:8 http://security.ubuntu.com/ubuntu bionic-security/universe amd64 DEP-11 Metadata [60.3 kB] Get:9 http://us.archive.ubuntu.com/ubuntu bionic-updates/main i386 Packages [1,288 kB] Get:10 http://security.ubuntu.com/ubuntu bionic-security/multiverse amd64 DEP-11 Metadata [2,464 B] Get:11 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages [2,070 kB] Get:12 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 DEP-11 Metadata [294 kB] Get:13 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 Packages [1,735 kB] Get:14 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe i386 Packages [1,567 kB] Get:15 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 DEP-11 Metadata [290 kB] Get:16 http://us.archive.ubuntu.com/ubuntu bionic-updates/multiverse amd64 DEP-11 Metadata [2,468 B] Get:17 http://us.archive.ubuntu.com/ubuntu bionic-backports/universe amd64 DEP-11 Metadata [9,288 B] Reading package lists... Done E: The repository 'https://launchpad.net/~sane-project/+archive/ubuntu/sane-release bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. $ cat /usr/lib/os-release NAME="Ubuntu" VERSION="18.04.5 LTS (Bionic Beaver)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 18.04.5 LTS" VERSION_ID="18.04" HOME_URL="https://www.ubuntu.com/"; SUPPORT_URL="https://help.ubuntu.com/"; BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"; PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"; VERSION_CODENAME=bionic UBUNTU_CODENAME=bionic
