The problem
I installed some software on Ubuntu, which I had not realised was very back level. It prompted and said
The following packages will be REMOVED:
fuse3 gnome-remote-desktop gnome-shell-extension-desktop-icons-ng gvfs-fuse nautilus
ntfs-3g shfs ubuntu-desktop-minimal ubuntu-session xdg-desktop-portal xdg-desktop-portal-gnome xdg-desktop-portal-gtk
Do you want to continue? [Y/n]
I blindly replied y – as I always do.
The next IPL failed to start, and left me in a command window with strange messages.
The cure
I rebooted, and selected a kernel with recovery mode.
This displayed a menu with
resume Resume normal boot
...
network Enable networking
root Drop into root shell mode
...
I selected network. This gave a window with
Continuing will remount your / filesystem in read/write mode. Do you wish to continue?
I clicked on <yes> .
Some status messages were displayed at the bottom of the screen, and it returned to the original menu.
At the menu I selected root. This gave me a command window with access to the network.
The magic command to restore Gnome was
sudo apt install gnome-desktop
This installed various packages.
I then issued
sudo shutdown now -r
and my Ubuntu came up as if nothing had happened.
Lessons learned
After I had recovered my Ubuntu, I remember doing this recovery before. Unfortunately I had written the recovery instructions in a file under my userid, but I could not find them during recovery. The wise thing to do is print off the instructions and keep a copy in my desk – or blog them as I’ve just done.
ColinPaice 