FWIW, the fix in focal-proposed looks good on my end as well.
I can confirm that the /etc/dhcp/dhclient-enter-hooks.d/resolved script now has the is-enabled check, and while I won't be able to test out resolvconf, I regard the updated conditional as equivalent to my previous known-good workaround (renaming the script to resolved.DISABLED, so it is not sourced by dhclient-script).
FWIW, the fix in focal-proposed looks good on my end as well.
I can confirm that the /etc/dhcp/ dhclient- enter-hooks. d/resolved script now has the is-enabled check, and while I won't be able to test out resolvconf, I regard the updated conditional as equivalent to my previous known-good workaround (renaming the script to resolved.DISABLED, so it is not sourced by dhclient-script).
Greatly appreciate the bug squash!