If you have time, could you try starting from Ubuntu 17.10, then upgrade to 18.04 and see if you can reproduce the issue? You're welcome to use a virtual machine to make testing easier.
** Tags added: bionic -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-software in Ubuntu. https://bugs.launchpad.net/bugs/1756098 Title: Potential cache upgrade issue in 3.28 results in unable to install flatpakref due to remote already existing To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1756098/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
