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Lubuntu 18.04.5 was the last Lubuntu to use the LXDE desktop, and supported upgrades can only be performed via re-install, ie. release notes of 18.10 & later contain text like the following (found in https://lubuntu.me/focal-2-released/) "Note, due to the extensive changes required for the shift in desktop environments, the Lubuntu team does not support upgrading from 18.04 or below to any greater release. Doing so will result in a broken system. If you are on 18.04 or below and would like to upgrade, please do a fresh install." The package `lubuntu-core` doesn't exist in any release past-18.04 as it was specific to LXDE. ie. $ rmadison lubuntu-core lubuntu-core | 0.38 | precise/universe | amd64, armel, armhf, i386, powerpc lubuntu-core | 0.55 | trusty/universe | amd64, armhf, i386, powerpc lubuntu-core | 0.65 | xenial/universe | amd64, armhf, i386, powerpc lubuntu-core | 0.65.3 | xenial-updates/universe | amd64, armhf, i386, powerpc lubuntu-core | 0.94 | bionic/universe | amd64, armhf, i386 lubuntu-core | 0.94.1 | bionic-updates/universe | amd64, armhf, i386 Lubuntu 18.04 LTS was the end-of-the-road for the `lubuntu-core`(LXDE; https://packages.ubuntu.com/bionic-updates/lubuntu-core) package. It should have been removed, and your system made a Ubuntu system if you intended upgrade; as the Lubuntu system requires re-install as per documentation. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1930648 Title: lubuntu 18.04.5 cannot partially upgrade To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1930648/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
