Install fails on ubunto 20.4

Install script fails with the following:

Installing NuttX dependencies
Reading package lists…
Building dependency tree…
Reading state information…
Package gcc-multilib is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Unable to locate package g+±multilib
E: Couldn’t find any package by regex ‘g+±multilib’
E: Package ‘gcc-multilib’ has no installation candidate

I posted about this a couple of weeks ago on Debian on RPI4 and BeagleBone Blue. It was recommened to use the supported Ubuntu release. I finally got around to changing OSs, unfortunately the exact same error continues. Any suggestions would be appreciated. Thank you.

It seems that this thread has the solution. At least it got through the setup, including Nuttx. Though the question if there is any degradation is not really answered.
Relogin or reboot computer before attempting to build NuttX targets · Issue #18180 · PX4/PX4-Autopilot · GitHub