Installed 3.4.2-0ubuntu0.16.04.4 3.4.2-0ubuntu0.18.04.4 and 3.4.2-1ubuntu0.19.10.3 without issues.
Ran them through the test and they all no more expose the behavior to report "domain is utf8 flagged:".
Info for others that re-test this, you have to re-start the spamassassin service to pick up the new code.
Installed 3.4.2-0ubuntu0. 16.04.4 3.4.2-0ubuntu0. 18.04.4 and 3.4.2-1ubuntu0. 19.10.3 without issues.
Ran them through the test and they all no more expose the behavior to report "domain is utf8 flagged:".
Info for others that re-test this, you have to re-start the spamassassin service to pick up the new code.
Setting verification-done