Upgrading from LMDE 6 to LMDE 7 fails #123

I tried to upgrade two machines from LMDE 6 to LMDE 7, and in both cases during package installation (if i recall correctly) the upgrade failed leaving a white-on-black text console screen, with some messages on the first machine and just with the cursor on the other.

I had to hard reboot. After reboot, I received the GRUB menu for the new LMDE 7, but trying to boot it would just hang with the logo in the center of the screen.

In both cases I had to boot from a live USB system and use Timeshift to revert the upgrade.

There were a few foreign packages present on the systems (Zoom, VPN, etc.). If needed, I may uninstall them and retry. But it takes a long time (4GB of packages to download). If the problem is with foreign packages, I would expect a more graceful failure anyway.