Field notes from troubleshooting the WhaTap observability stack: symptoms, reproductions, root causes and fixes.https://wiki.yogawiranda.my.id/enThu, 01 Oct 2026 01:35:43 GMThttps://wiki.yogawiranda.my.id/posts/debugging/notihub-smtp-auth/https://wiki.yogawiranda.my.id/posts/debugging/notihub-smtp-auth/A Java mail client ignored mail.smtp.auth=false and failed with 'AUTH LOGIN failed' on a relay that required no authentication. Reproducing it with MailDev, and why blank credentials are not the same as no credentials.Tue, 29 Sep 2026 00:00:00 GMTdebuggingsmtpjavajavamailmaildevroot-cause