Created attachment 110366 [details] Screenshot of installer crash I tried to install KDE Neon on a ThinkPad T450 while I had no internet connection. The install failed at the very end, unable to install the grub efi package. I was doing this on a plane at 30000 ft, so there was no opportunity to get online. The error I got was "The 'grub-efi-amd64-signed' package failed to install into /target/. Without the GRUB boot loader, the installed system will not boot.'. (see attached screenshot) It's right too, I was left with an un-bootable system :) I attempted this multiple times and the same error occurred. Once I got an internet connection, I ran the installer again on the same machine from the same media, and it worked fine. This is likely because a package hasn't been staged on the ISO, so requires a net connection to install.
Sorry about the aeroplane-mode install failure. We have our best looking engineers on it.
*** This bug has been marked as a duplicate of bug 380470 ***