Jean-Baptiste, your efibootmgr -v output shows no fewer than 18 boot entries for Ubuntu. That didn't happen as a result of a single install of Ubuntu (.... I hope). I think Dimitri's suggestion is that you zero these out, either with efibootmgr or from the firmware UI, to see if the system is less confused then and able to boot after install.
Like Dimitri, I do not see any evidence here of an Ubuntu bug, or if there is a bug, what that bug would be. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1796260 Title: UEFI installation alongside BIOS installation: System BootOrder not found To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1796260/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs