Date: Thu, 27 Apr 2017 22:16:23 +0200 From: To: Subject: hidden alternative attachment Message-Id: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="------alternative" --------alternative Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable This is the plain text part --------alternative Content-Type: multipart/mixed; boundary="------mixed" --------mixed Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit

This is the HTML part

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