diff --git a/messageviewer/src/messagepartthemes/default/cachehtmlwriter.h b/messageviewer/src/messagepartthemes/default/cachehtmlwriter.h
deleted file mode 100644
--- a/messageviewer/src/messagepartthemes/default/cachehtmlwriter.h
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
-   Copyright (c) 2016 Sandro Knauß <sknauss@kde.org>
-
-   This library is free software; you can redistribute it and/or modify it
-   under the terms of the GNU Library General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or (at your
-   option) any later version.
-
-   This library is distributed in the hope that it will be useful, but WITHOUT
-   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
-   License for more details.
-
-   You should have received a copy of the GNU Library General Public License
-   along with this library; see the file COPYING.LIB.  If not, write to the
-   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301, USA.
-*/
-
-#ifndef MESSAGEVIEWER_CACHEHTMLWRITER_H
-#define MESSAGEVIEWER_CACHEHTMLWRITER_H
-
-#include "messageviewer_export.h"
-#include <MimeTreeParser/BufferedHtmlWriter>
-
-#include <QMap>
-
-namespace MessageViewer {
-
-/** @deprecated port to proper streaming API */
-class MESSAGEVIEWER_DEPRECATED CacheHtmlWriter : public MimeTreeParser::BufferedHtmlWriter
-{
-public:
-    explicit CacheHtmlWriter(MimeTreeParser::HtmlWriter *baseWriter = nullptr)
-        : mBaseWriter(baseWriter)
-    {
-        BufferedHtmlWriter::begin();
-    }
-    ~CacheHtmlWriter() = default;
-
-    void embedPart(const QByteArray &contentId, const QString &url) override
-    {
-        if (mBaseWriter)
-            mBaseWriter->embedPart(contentId, url);
-        else
-            embedParts.insert(contentId, url);
-    }
-
-    void extraHead(const QString &extra) override
-    {
-        if (mBaseWriter)
-            mBaseWriter->extraHead(extra);
-        else
-            head.append(extra);
-    }
-
-    QString html()
-    {
-        BufferedHtmlWriter::end();
-        return QString::fromUtf8(data());
-    }
-
-    QString head;
-    QMap<QByteArray, QString> embedParts;
-
-private:
-    MimeTreeParser::HtmlWriter *mBaseWriter = nullptr;
-};
-
-}
-
-#endif // MESSAGEVIEWER_CACHEHTMLWRITER_H
diff --git a/messageviewer/src/messagepartthemes/default/defaultrenderer.h b/messageviewer/src/messagepartthemes/default/defaultrenderer.h
--- a/messageviewer/src/messagepartthemes/default/defaultrenderer.h
+++ b/messageviewer/src/messagepartthemes/default/defaultrenderer.h
@@ -20,8 +20,6 @@
 #ifndef __MESSAGEVIEWER_DEFAULTRENDERER_H__
 #define __MESSAGEVIEWER_DEFAULTRENDERER_H__
 
-#include <MimeTreeParser/MessagePartRenderer>
-
 #include <QSharedPointer>
 
 namespace MimeTreeParser {
@@ -34,14 +32,12 @@
 namespace MessageViewer {
 class CSSHelperBase;
 
-class DefaultRenderer : public MimeTreeParser::Interface::MessagePartRenderer
+class DefaultRenderer
 {
 public:
     DefaultRenderer(const MimeTreeParser::MessagePartPtr &msgPart, CSSHelperBase *cssHelder, MimeTreeParser::HtmlWriter *writer);
     ~DefaultRenderer();
 
-    QString html() const override;
-
 private:
     MimeTreeParser::DefaultRendererPrivate *d;
 };
diff --git a/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp b/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp
--- a/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp
+++ b/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp
@@ -23,7 +23,6 @@
 
 #include "messageviewer_debug.h"
 
-#include "cachehtmlwriter.h"
 #include "converthtmltoplaintext.h"
 #include "messagepartrendererbase.h"
 #include "messagepartrendererfactory.h"
@@ -56,14 +55,9 @@
 #include <grantlee/templateloader.h>
 #include <grantlee/template.h>
 
-#include <functional>
-
 using namespace MimeTreeParser;
 using namespace MessageViewer;
 
-typedef std::function<void(Grantlee::OutputStream *stream)> GrantleeCallback;
-Q_DECLARE_METATYPE(GrantleeCallback)
-
 Q_DECLARE_METATYPE(GpgME::DecryptionResult::Recipient)
 Q_DECLARE_METATYPE(const QGpgME::Protocol *)
 
@@ -315,11 +309,10 @@
 
 DefaultRendererPrivate::DefaultRendererPrivate(const MessagePart::Ptr &msgPart, CSSHelperBase *cssHelper, HtmlWriter *writer, const MessagePartRendererFactory *rendererFactory)
     : mMsgPart(msgPart)
-    , mOldWriter(writer)
     , mCSSHelper(cssHelper)
     , mRendererFactory(rendererFactory)
 {
-    mHtml = renderFactory(mMsgPart, nullptr);
+    renderFactory(mMsgPart, writer);
 }
 
 DefaultRendererPrivate::~DefaultRendererPrivate()
@@ -339,7 +332,7 @@
 void DefaultRendererPrivate::renderSubParts(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter)
 {
     foreach (const auto &m, msgPart->subParts())
-        htmlWriter->write(renderFactory(m, htmlWriter));
+        renderFactory(m, htmlWriter);
 }
 
 void DefaultRendererPrivate::render(const MessagePartList::Ptr &mp, HtmlWriter *htmlWriter)
@@ -850,61 +843,59 @@
     return false;
 }
 
-QString DefaultRendererPrivate::renderFactory(const MessagePart::Ptr &msgPart, HtmlWriter *_htmlWriter)
+void DefaultRendererPrivate::renderFactory(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter)
 {
-    auto htmlWriter = QSharedPointer<CacheHtmlWriter>(new CacheHtmlWriter(mOldWriter));
     const QString className = QString::fromUtf8(msgPart->metaObject()->className());
 
-    if (renderWithFactory(className, msgPart, htmlWriter.data()))
-        return htmlWriter->html();
+    if (renderWithFactory(className, msgPart, htmlWriter))
+        return;
 
     if (className == QStringLiteral("MimeTreeParser::MessagePartList")) {
         auto mp = msgPart.dynamicCast<MessagePartList>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::MimeMessagePart")) {
         auto mp = msgPart.dynamicCast<MimeMessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::EncapsulatedRfc822MessagePart")) {
         auto mp = msgPart.dynamicCast<EncapsulatedRfc822MessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::HtmlMessagePart")) {
         auto mp = msgPart.dynamicCast<HtmlMessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::SignedMessagePart")) {
         auto mp = msgPart.dynamicCast<SignedMessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::EncryptedMessagePart")) {
         auto mp = msgPart.dynamicCast<EncryptedMessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::AlternativeMessagePart")) {
         auto mp = msgPart.dynamicCast<AlternativeMessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::CertMessagePart")) {
         auto mp = msgPart.dynamicCast<CertMessagePart>();
         if (mp) {
-            render(mp, htmlWriter.data());
+            render(mp, htmlWriter);
         }
     } else if (auto mp = msgPart.dynamicCast<LegacyPluginMessagePart>()) {
-        return mp->formatOutput();
+        htmlWriter->write(mp->formatOutput());
     } else {
         qCWarning(MESSAGEVIEWER_LOG) << "We got a unkonwn classname, using default behaviour for "
                                << className;
     }
-    return htmlWriter->html();
 }
 
 DefaultRenderer::DefaultRenderer(const MimeTreeParser::MessagePart::Ptr &msgPart, CSSHelperBase *cssHelper, MimeTreeParser::HtmlWriter *writer)
@@ -916,8 +907,3 @@
 {
     delete d;
 }
-
-QString DefaultRenderer::html() const
-{
-    return d->mHtml;
-}
diff --git a/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h b/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h
--- a/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h
+++ b/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h
@@ -46,7 +46,7 @@
 
     Interface::ObjectTreeSource *source() const;
 
-    void renderSubParts(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter);
+    void renderSubParts(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter) override;
 
     void render(const MessagePartList::Ptr &mp, HtmlWriter *htmlWriter);
     void render(const MimeMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
@@ -59,12 +59,9 @@
     void render(const AlternativeMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     void render(const CertMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     bool renderWithFactory(const QString &className, const MessagePart::Ptr &msgPart, HtmlWriter *writer) override;
-    QString renderFactory(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter);
+    void renderFactory(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter);
 
-    QString mHtml;
     MessagePart::Ptr mMsgPart;
-    HtmlWriter *mOldWriter = nullptr;
-
     CSSHelperBase *mCSSHelper = nullptr;
     const MessageViewer::MessagePartRendererFactory *mRendererFactory = nullptr;
 };
diff --git a/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h b/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h
--- a/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h
+++ b/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h
@@ -54,6 +54,7 @@
 
     virtual CSSHelperBase* cssHelper() const = 0;
     virtual bool renderWithFactory(const QString &className, const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *writer) = 0;
+    virtual void renderSubParts(const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter) = 0;
 };
 
 class MESSAGEVIEWER_EXPORT MessagePartRendererBase
diff --git a/messageviewer/src/messagepartthemes/default/messagepartrenderermanager.h b/messageviewer/src/messagepartthemes/default/messagepartrenderermanager.h
--- a/messageviewer/src/messagepartthemes/default/messagepartrenderermanager.h
+++ b/messageviewer/src/messagepartthemes/default/messagepartrenderermanager.h
@@ -20,17 +20,24 @@
 #ifndef MESSAGEPARTRENDERERMANAGER_H
 #define MESSAGEPARTRENDERERMANAGER_H
 
-#include <QObject>
 #include "messageviewer_export.h"
+
 #include <grantlee/template.h>
 
+#include <QMetaType>
+#include <QObject>
+
+#include <functional>
+
 namespace GrantleeTheme {
 class Engine;
 }
 
 namespace MessageViewer {
 class GlobalContext;
 
+typedef std::function<void(Grantlee::OutputStream *stream)> GrantleeCallback;
+
 class MESSAGEVIEWER_EXPORT MessagePartRendererManager : public QObject
 {
     Q_OBJECT
@@ -48,4 +55,6 @@
 };
 }
 
+Q_DECLARE_METATYPE(MessageViewer::GrantleeCallback)
+
 #endif // MESSAGEPARTRENDERERMANAGER_H
diff --git a/messageviewer/src/messagepartthemes/default/plugins/textmessagepartrenderer.cpp b/messageviewer/src/messagepartthemes/default/plugins/textmessagepartrenderer.cpp
--- a/messageviewer/src/messagepartthemes/default/plugins/textmessagepartrenderer.cpp
+++ b/messageviewer/src/messagepartthemes/default/plugins/textmessagepartrenderer.cpp
@@ -54,16 +54,11 @@
     Grantlee::Template t;
     Grantlee::Context c = MessagePartRendererManager::self()->createContext();
     c.insert(QStringLiteral("block"), msgPart.data());
-
+    c.insert(QStringLiteral("content"), QVariant::fromValue<GrantleeCallback>([mp, htmlWriter, context](Grantlee::OutputStream*) {
+        context->renderSubParts(mp, htmlWriter);
+    }));
     t = MessagePartRendererManager::self()->loadByName(QStringLiteral(":/textmessagepart.html"));
 
-    QString content;
-    foreach (const auto &_m, mp->subParts()) {
-        DefaultRenderer::Ptr renderer = mp->source()->messagePartTheme(_m);
-        content += renderer->html();
-    }
-    c.insert(QStringLiteral("content"), content);
-
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
     return true;
diff --git a/messageviewer/src/messagepartthemes/default/templates/textmessagepart.html b/messageviewer/src/messagepartthemes/default/templates/textmessagepart.html
--- a/messageviewer/src/messagepartthemes/default/templates/textmessagepart.html
+++ b/messageviewer/src/messagepartthemes/default/templates/textmessagepart.html
@@ -19,12 +19,12 @@
         </tr>
         <tr class="textAtmB">
             <td>
-                {{content|safe}}
+                {% callback content %}
             </td>
         </tr>
     </table>
 {% else %}
-    {{content|safe}}
+    {% callback content %}
 {% endif %}
 {% if block.isAttachment %}
 </div>
diff --git a/messageviewer/src/messagepartthemes/grantlee/grantleeextension.h b/messageviewer/src/messagepartthemes/grantlee/grantleeextension.h
--- a/messageviewer/src/messagepartthemes/grantlee/grantleeextension.h
+++ b/messageviewer/src/messagepartthemes/grantlee/grantleeextension.h
@@ -25,8 +25,12 @@
 
 #include <QObject>
 
+#include <functional>
+
 namespace MessageViewer {
 
+typedef std::function<void(Grantlee::OutputStream *stream)> GrantleeCallback;
+
 class CallbackTag : public Grantlee::Node
 {
     Q_OBJECT
@@ -57,4 +61,6 @@
 
 }
 
+Q_DECLARE_METATYPE(MessageViewer::GrantleeCallback)
+
 #endif // MESSAGEVIEWER_GRANTLEEEXTENSION_H
diff --git a/messageviewer/src/messagepartthemes/grantlee/grantleeextension.cpp b/messageviewer/src/messagepartthemes/grantlee/grantleeextension.cpp
--- a/messageviewer/src/messagepartthemes/grantlee/grantleeextension.cpp
+++ b/messageviewer/src/messagepartthemes/grantlee/grantleeextension.cpp
@@ -24,13 +24,8 @@
 
 #include <QDebug>
 
-#include <functional>
-
 using namespace MessageViewer;
 
-typedef std::function<void(Grantlee::OutputStream *stream)> GrantleeCallback;
-Q_DECLARE_METATYPE(GrantleeCallback)
-
 CallbackTag::CallbackTag(const QString &name, QObject* parent)
     : Grantlee::Node(parent)
     , m_name(name)
diff --git a/messageviewer/src/viewer/objecttreeemptysource.h b/messageviewer/src/viewer/objecttreeemptysource.h
--- a/messageviewer/src/viewer/objecttreeemptysource.h
+++ b/messageviewer/src/viewer/objecttreeemptysource.h
@@ -51,8 +51,7 @@
     bool showEmoticons() const override;
     bool showExpandQuotesMark() const override;
     const MimeTreeParser::BodyPartFormatterBaseFactory *bodyPartFormatterFactory() override;
-    MimeTreeParser::Interface::MessagePartRendererPtr messagePartTheme(
-        MimeTreeParser::MessagePartPtr msgPart) override;
+    void render(const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter) override;
     bool isPrinting() const override;
 private:
     EmptySourcePrivate *const d;
diff --git a/messageviewer/src/viewer/objecttreeemptysource.cpp b/messageviewer/src/viewer/objecttreeemptysource.cpp
--- a/messageviewer/src/viewer/objecttreeemptysource.cpp
+++ b/messageviewer/src/viewer/objecttreeemptysource.cpp
@@ -141,9 +141,7 @@
     return false;
 }
 
-MimeTreeParser::Interface::MessagePartRendererPtr EmptySource::messagePartTheme(
-    MimeTreeParser::MessagePartPtr msgPart)
+void EmptySource::render(const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter)
 {
-    return MimeTreeParser::Interface::MessagePartRenderer::Ptr(
-        new DefaultRenderer(msgPart, cssHelper(), htmlWriter()));
+    DefaultRenderer(msgPart, cssHelper(), htmlWriter);
 }
diff --git a/messageviewer/src/viewer/objecttreeviewersource.h b/messageviewer/src/viewer/objecttreeviewersource.h
--- a/messageviewer/src/viewer/objecttreeviewersource.h
+++ b/messageviewer/src/viewer/objecttreeviewersource.h
@@ -48,8 +48,7 @@
     bool showEmoticons() const override;
     bool showExpandQuotesMark() const override;
     const MimeTreeParser::BodyPartFormatterBaseFactory *bodyPartFormatterFactory() override;
-    MimeTreeParser::Interface::MessagePartRendererPtr messagePartTheme(
-        MimeTreeParser::MessagePartPtr msgPart) override;
+    void render(const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter) override;
     bool isPrinting() const override;
 private:
     ViewerPrivate *mViewer = nullptr;
diff --git a/messageviewer/src/viewer/objecttreeviewersource.cpp b/messageviewer/src/viewer/objecttreeviewersource.cpp
--- a/messageviewer/src/viewer/objecttreeviewersource.cpp
+++ b/messageviewer/src/viewer/objecttreeviewersource.cpp
@@ -129,9 +129,7 @@
     return mViewer->mPrinting;
 }
 
-MimeTreeParser::Interface::MessagePartRendererPtr MailViewerSource::messagePartTheme(
-    MimeTreeParser::MessagePartPtr msgPart)
+void MailViewerSource::render(const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter)
 {
-    return MimeTreeParser::Interface::MessagePartRenderer::Ptr(
-        new DefaultRenderer(msgPart, mViewer->cssHelper(), mViewer->htmlWriter()));
+    DefaultRenderer(msgPart, mViewer->cssHelper(), htmlWriter);
 }
diff --git a/mimetreeparser/autotests/setupenv.h b/mimetreeparser/autotests/setupenv.h
--- a/mimetreeparser/autotests/setupenv.h
+++ b/mimetreeparser/autotests/setupenv.h
@@ -26,7 +26,6 @@
 #include <MimeTreeParser/BodyPartFormatter>
 #include <MimeTreeParser/BodyPartFormatterBaseFactory>
 #include <MimeTreeParser/MessagePart>
-#include <MimeTreeParser/MessagePartRenderer>
 #include <MimeTreeParser/ObjectTreeSource>
 
 namespace MimeTreeParser {
@@ -149,10 +148,10 @@
         return QString(); //do nothing
     }
 
-    Interface::MessagePartRenderer::Ptr messagePartTheme(MessagePart::Ptr msgPart) override
+    void render(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter) override
     {
         Q_UNUSED(msgPart);
-        return Interface::MessagePartRenderer::Ptr();
+        Q_UNUSED(htmlWriter);
     }
 
     bool isPrinting() const override
diff --git a/mimetreeparser/src/CMakeLists.txt b/mimetreeparser/src/CMakeLists.txt
--- a/mimetreeparser/src/CMakeLists.txt
+++ b/mimetreeparser/src/CMakeLists.txt
@@ -23,7 +23,6 @@
     interfaces/objecttreesource.cpp
     interfaces/bodypart.cpp
     interfaces/htmlwriter.cpp
-    interfaces/messagepartrenderer.cpp
     job/qgpgmejobexecutor.cpp
     utils/util.cpp
     viewer/attachmentstrategy.cpp
@@ -78,7 +77,6 @@
     BodyPartFormatter
     BodyPart
     HtmlWriter
-    MessagePartRenderer
     ObjectTreeSource
     REQUIRED_HEADERS MimeTreeParser_interfaces_HEADERS
     PREFIX MimeTreeParser
diff --git a/mimetreeparser/src/interfaces/messagepartrenderer.h b/mimetreeparser/src/interfaces/messagepartrenderer.h
deleted file mode 100644
--- a/mimetreeparser/src/interfaces/messagepartrenderer.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
-  Copyright (C) 2016 Sandro Knauß <sknauss@kde.org>
-
-  This program is free software; you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
-  (at your option) any later version.
-
-  This program is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License along
-  with this program; if not, write to the Free Software Foundation, Inc.,
-  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
-*/
-
-#ifndef __MIMETREEPARSER_MESSAGEPARTRENDERER_IF_H__
-#define __MIMETREEPARSER_MESSAGEPARTRENDERER_IF_H__
-
-#include "mimetreeparser_export.h"
-
-#include <QSharedPointer>
-
-namespace MimeTreeParser {
-namespace Interface {
-/**
-* Interface for rendering messageparts to html.
-* @author Andras Mantia <sknauss@kde.org>
-*/
-class MIMETREEPARSER_EXPORT MessagePartRenderer
-{
-public:
-    typedef QSharedPointer<MessagePartRenderer> Ptr;
-
-    virtual ~MessagePartRenderer();
-
-    virtual QString html() const = 0;
-};
-}
-}
-#endif
diff --git a/mimetreeparser/src/interfaces/messagepartrenderer.cpp b/mimetreeparser/src/interfaces/messagepartrenderer.cpp
deleted file mode 100644
--- a/mimetreeparser/src/interfaces/messagepartrenderer.cpp
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
-  Copyright (C) 2016 Sandro Knauß <sknauss@kde.org>
-
-  This program is free software; you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
-  (at your option) any later version.
-
-  This program is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License along
-  with this program; if not, write to the Free Software Foundation, Inc.,
-  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
-*/
-
-#include "messagepartrenderer.h"
-
-MimeTreeParser::Interface::MessagePartRenderer::~MessagePartRenderer()
-{
-}
diff --git a/mimetreeparser/src/interfaces/objecttreesource.h b/mimetreeparser/src/interfaces/objecttreesource.h
--- a/mimetreeparser/src/interfaces/objecttreesource.h
+++ b/mimetreeparser/src/interfaces/objecttreesource.h
@@ -34,10 +34,6 @@
 class BodyPartFormatterBaseFactory;
 class MessagePart;
 typedef QSharedPointer<MessagePart> MessagePartPtr;
-namespace Interface {
-class MessagePartRenderer;
-typedef QSharedPointer<MessagePartRenderer> MessagePartRendererPtr;
-}
 }
 
 namespace MimeTreeParser {
@@ -93,7 +89,7 @@
 
     virtual const BodyPartFormatterBaseFactory *bodyPartFormatterFactory() = 0;
 
-    virtual MessagePartRendererPtr messagePartTheme(MessagePartPtr msgPart) = 0;
+    virtual void render(const MessagePartPtr &msgPart, HtmlWriter *htmlWriter) = 0;
 
     virtual bool isPrinting() const = 0;
 
diff --git a/mimetreeparser/src/viewer/objecttreeparser.cpp b/mimetreeparser/src/viewer/objecttreeparser.cpp
--- a/mimetreeparser/src/viewer/objecttreeparser.cpp
+++ b/mimetreeparser/src/viewer/objecttreeparser.cpp
@@ -47,7 +47,6 @@
 #include "bodyformatter/utils.h"
 #include "interfaces/bodypartformatter.h"
 #include "interfaces/htmlwriter.h"
-#include "interfaces/messagepartrenderer.h"
 #include "utils/util.h"
 
 #include <KMime/Headers>
@@ -184,10 +183,7 @@
         }
 
         if (htmlWriter()) {
-            const auto renderer = mSource->messagePartTheme(mParsedPart);
-            if (renderer) {
-                htmlWriter()->write(renderer->html());
-            }
+            mSource->render(mParsedPart, htmlWriter());
         }
     }
 }