After copying Ubuntu 21.04 to a new drive (it is an Ubuntu-only system), I need to repair the boot but not sure how to do so. It boots to Grub, then goes to initramfs but it can go to the Grub command line by pressing c. Can it be repaired from the Grub command line? I see many other posts here and elsewhere about this very issue but nothing I tried seemed to work.
Trying to boot to the live DVD, it gives many errors (Failed to start Snap Daemon
and Failed to start Holds Snappy daemon refresh
among others) then eventually goes to a blank screen with only the cursor.