Thanks for the swift update, Chris. As you say, it looks like an issue with grub2. The end of support for this particular Lubuntu flavour had slipped my mind. Sigh.
Looking at the /boot/efi/EFI/ubuntu/grub.cfg I see #cat /boot/efi/EFI/ubuntu/grub.cfg search.fs_uuid xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx root lvmid/yyyyyy-yyyy-yyyy-yyyy-yyyy-yyyy-yyyyyy/zzzzzz-zzzz-zzzz-zzzz-zzzz-zzzz-zzzzzz set prefix=($root)'/grub' configfile $prefix/grub.cfg The various UUIDs are all correct for my setup (UEFI. Clear-text ESP. Encrypted partition containing LVM volumes, with separate volumes for boot, root, home, var...) The search.fs_uuid will fail if the key for the encrypted partition has not been given and the encrypted partition opened via cryptomount first, so it looks like update-grub is missing something it didn't before, which, I guess, has something to do with the transition from grub 2.02 to grub 2.04. Running update-grub does not fix the problem. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1927853 Title: Update to grub 2.04-1ubuntu44 breaks booting To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lubuntu-meta/+bug/1927853/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs