PPAs are not suppoerted by Ubuntu and may cause problems when upgrading the system. Please follow the advice given by oibaf and also apply the procedure to other PPAs if necessary.
>From https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers: === Upgrading to a newer Ubuntu === It is *strongly* suggested to remove all packages from this PPA before updating to a newer Ubuntu release. See the section "Revert to original drivers" later on. Then, after the upgrade, you can add again this PPA. === Revert to original drivers === To revert to standard Ubuntu drivers type the following in a prompt shell: $ sudo apt-get install ppa-purge $ sudo ppa-purge ppa:oibaf/graphics-drivers ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1809531 Title: upgrading issue To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1809531/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
