From - Sat Oct 10 11:57:00 2026
X-Mozilla-Status: 0001
X-Mozilla-Status2: 00000000
Date: Sat, 10 Oct 2026 11:57:00 +0200
Message-Id: <bug391717-missing-from@example.invalid>
To: PrimaryEmail1@test.invalid
Subject: Bug 391717 missing sender test
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8

Bug 391717 test message with no From header.