MailboxTester required a usable SECRETS_KEY unconditionally, refusing an
unauthenticated relay's test-send on a fresh install with no key yet, even
though real sending never touches the cipher for that mailbox. Gated the
check on authenticates, same as the password-presence check beside it.
Comparison pass across MailboxTester and MailboxTransport turned up two more
of the same shape. MailboxTransport's delegate-cache fingerprint decrypted
$box->password unconditionally, even when unauthenticated and never going to
use it — a mailbox that once authenticated, stored a password, and later had
authenticates unchecked would crash real sending the moment SECRETS_KEY
became unusable. And MailboxTester had no guard against a stored port <1;
Symfony silently reinterprets that as port 25 rather than refusing it, so the
test button could reach whatever happens to listen there and report success
for a configuration MailboxTransport refuses outright.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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