package has invalid Support Legacyheader

[Leo]

Having recently upgraded 20.10 -> 21.04 it is no longer possible to install the nvidia drivers. Running: ubuntu-drivers devices
Outputs:
WARNING:root:_pkg_get_support nvidia-driver-390: package has invalid Support Legacyheader, cannot determine support level
== /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 ==
modalias : pci:v000010DEd00001184sv00001458sd00003603bc03sc00i00
vendor : NVIDIA Corporation
model : GK104 [GeForce GTX 770]
driver : nvidia-driver-460 - distro non-free recommended
driver : nvidia-driver-450-server - distro non-free
driver : nvidia-driver-465 - distro non-free
driver : nvidia-driver-460-server - distro non-free
driver : nvidia-driver-390 - distro non-free
driver : nvidia-driver-418-server - distro non-free
driver : xserver-xorg-video-nouveau - distro free builtin

Running: ubuntu-drivers install nvidia-driver-460
Outputs:
WARNING:root:_pkg_get_support nvidia-driver-390: package has invalid Support Legacyheader, cannot determine support level
No drivers found for installation.

I've tried:
apt-get remove --purge "nvidia*" libnvidia-ifr1-460
and then re-doing the ubuntu-drivers commands. But that doesn't make a difference.

ProblemType: Bug
DistroRelease: Ubuntu 21.04
Package: ubuntu-drivers-common 1:0.9.0~0.21.04.1
ProcVersionSignature: Ubuntu 5.11.0-24.25-generic 5.11.22
Uname: Linux 5.11.0-24-generic x86_64
ApportVersion: 2.20.11-0ubuntu65.1
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: XFCE
Date: Wed Jul 7 11:01:07 2021
InstallationDate: Installed on 2017-05-13 (1515 days ago)
InstallationMedia: Xubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
SourcePackage: ubuntu-drivers-common
UpgradeStatus: Upgraded to hirsute on 2021-07-04 (2 days ago)

[Leo (linux-fractal)]

So the Support Legacyheader was a red herring.

Debugging the ubuntu-drivers python showed that
ubuntu-drivers install
calls the following:
apt-get install -o DPkg::options::=--force-confnew -y nvidia-driver-460 linux-modules-nvidia-460-generic

when run manually this gives the output:
Preparing to unpack .../libnvidia-gl-460_460.84-0ubuntu0.21.04.1_amd64.deb ...
diversion of /usr/lib/x86_64-linux-gnu/libGL.so.1 to /usr/lib/x86_64-linux-gnu/libGL.so.1.distrib by nvidia-340
dpkg-divert: error: mismatch on package
  when removing 'diversion of /usr/lib/x86_64-linux-gnu/libGL.so.1 by libnvidia-gl-460'
  found 'diversion of /usr/lib/x86_64-linux-gnu/libGL.so.1 to /usr/lib/x86_64-linux-gnu/libGL.so.1.distrib by nvidia-340'
dpkg: error processing archive /var/cache/apt/archives/libnvidia-gl-460_460.84-0ubuntu0.21.04.1_amd64.deb (--unpack):
 new libnvidia-gl-460:amd64 package pre-installation script subprocess returned error exit status 2
Selecting previously unselected package libnvidia-ifr1-460:amd64.
Preparing to unpack .../libnvidia-ifr1-460_460.84-0ubuntu0.21.04.1_amd64.deb ...
Unpacking libnvidia-ifr1-460:amd64 (460.84-0ubuntu0.21.04.1) ...
Selecting previously unselected package linux-modules-nvidia-460-generic.
Preparing to unpack .../linux-modules-nvidia-460-generic_5.11.0-24.25_amd64.deb ...
Unpacking linux-modules-nvidia-460-generic (5.11.0-24.25) ...
Selecting previously unselected package nvidia-driver-460.
Preparing to unpack .../nvidia-driver-460_460.84-0ubuntu0.21.04.1_amd64.deb ...
Unpacking nvidia-driver-460 (460.84-0ubuntu0.21.04.1) ...
Errors were encountered while processing:
 /var/cache/apt/archives/libnvidia-gl-460_460.84-0ubuntu0.21.04.1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

So perhaps something did get cleaned up correctly in the upgrade? Searching for this error led me to: https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-390/+bug/1768050 where the suggested fix for running dpkg-divert --remove, resulted in ubuntu-drivers install running successfully.

Not sure why this output didn't show up when I initially call ubuntu-drivers from the cmd line. Perhaps because the GUI had already called it and now apt was unhappy there was no output, just a non-zero return code?