UTF encoding shown in not parsed when displaying messages

[iandunn]

I’m getting email threads split out with this at the start: ⁠⁠⁠⁠=?UTF-8?Q?Re=3A_=231074=3A_Re=3A_⁠⁠⁠⁠

Reported at https://wordpress.slack.com/archives/meta-wordcamp/p1469476302000091

Delivered-To: email@mydomain.com
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Mon, 25 Jul 2016 15:30:32 -0700 (PDT)
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Mon, 25 Jul 2016 15:30:32 -0700 (PDT)
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for email@mydomain.com
(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
Mon, 25 Jul 2016 15:30:32 -0700 (PDT)
Received-SPF: pass (google.com: domain of singapore@wordcamp.org designates 66.155.40.24 as permitted sender) client-ip=66.155.40.24;
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of singapore@wordcamp.org designates 66.155.40.24 as permitted sender) smtp.mailfrom=singapore@wordcamp.org;
dmarc=pass (p=NONE dis=NONE) header.from=wordcamp.org
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by marx.multipattern.com with esmtpa (Exim 4.87)
(envelope-from singapore@wordcamp.org)
id 1bRoOK-00010L-Vx; Mon, 25 Jul 2016 22:30:29 +0000
Date: Mon, 25 Jul 2016 22:30:29 +0000
To: receiver@hisdomain.com, email@mydomain.com
From: WordCamp Singapore 2016 singapore@wordcamp.org
Subject: =?UTF-8?Q?Re:_#1068:Re:Speaking_at_WordCamp_SG=E2=80=94_please_let_us?=
=?UTF-8?Q?know_how_long_your_talk_will_be!?=
Message-ID: 71e5c38284af389816a9ec3df2567c66@wordcamp.org
X-Mailer: PHPMailer 5.2.14 (https://github.com/PHPMailer/PHPMailer)
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