diff --git a/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp b/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp
index b7475e45..31b0f1a9 100644
--- a/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp
+++ b/messageviewer/src/messagepartthemes/default/defaultrenderer.cpp
@@ -1,911 +1,911 @@
 /*
    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.
 */
 
 #include "defaultrenderer.h"
 
 #include "defaultrenderer_p.h"
 
 #include "messageviewer_debug.h"
 
 #include "converthtmltoplaintext.h"
 #include "messagepartrendererbase.h"
 #include "messagepartrendererfactory.h"
 #include "htmlblock.h"
 
 #include "utils/iconnamecache.h"
 #include "utils/mimetype.h"
 #include "viewer/csshelperbase.h"
 #include "messagepartrenderermanager.h"
 
 #include <MimeTreeParser/BufferedHtmlWriter>
 #include <MimeTreeParser/MessagePart>
 #include <MimeTreeParser/ObjectTreeParser>
 #include <GrantleeTheme/QtResourceTemplateLoader>
 
 #include <QGpgME/Protocol>
 
 #include <MessageCore/StringUtil>
 
 #include <KEmailAddress>
 #include <KIconLoader>
 #include <KLocalizedString>
 
 #include <QApplication>
 #include <QUrl>
 
 #include <grantlee/context.h>
 #include <grantlee/engine.h>
 #include <grantlee/metatype.h>
 #include <grantlee/templateloader.h>
 #include <grantlee/template.h>
 
 using namespace MimeTreeParser;
 using namespace MessageViewer;
 
 Q_DECLARE_METATYPE(GpgME::DecryptionResult::Recipient)
 Q_DECLARE_METATYPE(const QGpgME::Protocol *)
 
 static const int SIG_FRAME_COL_UNDEF = 99;
 #define SIG_FRAME_COL_RED    -1
 #define SIG_FRAME_COL_YELLOW  0
 #define SIG_FRAME_COL_GREEN   1
 QString sigStatusToString(const QGpgME::Protocol *cryptProto, int status_code, GpgME::Signature::Summary summary, int &frameColor, bool &showKeyInfos)
 {
     // note: At the moment frameColor and showKeyInfos are
     //       used for CMS only but not for PGP signatures
     // pending(khz): Implement usage of these for PGP sigs as well.
     showKeyInfos = true;
     QString result;
     if (cryptProto) {
         if (cryptProto == QGpgME::openpgp()) {
             // process enum according to it's definition to be read in
             // GNU Privacy Guard CVS repository /gpgme/gpgme/gpgme.h
             switch (status_code) {
             case 0: // GPGME_SIG_STAT_NONE
                 result = i18n("Error: Signature not verified");
                 break;
             case 1: // GPGME_SIG_STAT_GOOD
                 result = i18n("Good signature");
                 break;
             case 2: // GPGME_SIG_STAT_BAD
                 result = i18n("Bad signature");
                 break;
             case 3: // GPGME_SIG_STAT_NOKEY
                 result = i18n("No public key to verify the signature");
                 break;
             case 4: // GPGME_SIG_STAT_NOSIG
                 result = i18n("No signature found");
                 break;
             case 5: // GPGME_SIG_STAT_ERROR
                 result = i18n("Error verifying the signature");
                 break;
             case 6: // GPGME_SIG_STAT_DIFF
                 result = i18n("Different results for signatures");
                 break;
             /* PENDING(khz) Verify exact meaning of the following values:
             case 7: // GPGME_SIG_STAT_GOOD_EXP
             return i18n("Signature certificate is expired");
             break;
             case 8: // GPGME_SIG_STAT_GOOD_EXPKEY
             return i18n("One of the certificate's keys is expired");
             break;
             */
             default:
                 result.clear();   // do *not* return a default text here !
                 break;
             }
         } else if (cryptProto == QGpgME::smime()) {
             // process status bits according to SigStatus_...
             // definitions in kdenetwork/libkdenetwork/cryptplug.h
 
             if (summary == GpgME::Signature::None) {
                 result = i18n("No status information available.");
                 frameColor = SIG_FRAME_COL_YELLOW;
                 showKeyInfos = false;
                 return result;
             }
 
             if (summary & GpgME::Signature::Valid) {
                 result = i18n("Good signature.");
                 // Note:
                 // Here we are work differently than KMail did before!
                 //
                 // The GOOD case ( == sig matching and the complete
                 // certificate chain was verified and is valid today )
                 // by definition does *not* show any key
                 // information but just states that things are OK.
                 //           (khz, according to LinuxTag 2002 meeting)
                 frameColor = SIG_FRAME_COL_GREEN;
                 showKeyInfos = false;
                 return result;
             }
 
             // we are still there?  OK, let's test the different cases:
 
             // we assume green, test for yellow or red (in this order!)
             frameColor = SIG_FRAME_COL_GREEN;
             QString result2;
             if (summary & GpgME::Signature::KeyExpired) {
                 // still is green!
                 result2 = i18n("One key has expired.");
             }
             if (summary & GpgME::Signature::SigExpired) {
                 // and still is green!
                 result2 += i18n("The signature has expired.");
             }
 
             // test for yellow:
             if (summary & GpgME::Signature::KeyMissing) {
                 result2 += i18n("Unable to verify: key missing.");
                 // if the signature certificate is missing
                 // we cannot show information on it
                 showKeyInfos = false;
                 frameColor = SIG_FRAME_COL_YELLOW;
             }
             if (summary & GpgME::Signature::CrlMissing) {
                 result2 += i18n("CRL not available.");
                 frameColor = SIG_FRAME_COL_YELLOW;
             }
             if (summary & GpgME::Signature::CrlTooOld) {
                 result2 += i18n("Available CRL is too old.");
                 frameColor = SIG_FRAME_COL_YELLOW;
             }
             if (summary & GpgME::Signature::BadPolicy) {
                 result2 += i18n("A policy was not met.");
                 frameColor = SIG_FRAME_COL_YELLOW;
             }
             if (summary & GpgME::Signature::SysError) {
                 result2 += i18n("A system error occurred.");
                 // if a system error occurred
                 // we cannot trust any information
                 // that was given back by the plug-in
                 showKeyInfos = false;
                 frameColor = SIG_FRAME_COL_YELLOW;
             }
 
             // test for red:
             if (summary & GpgME::Signature::KeyRevoked) {
                 // this is red!
                 result2 += i18n("One key has been revoked.");
                 frameColor = SIG_FRAME_COL_RED;
             }
             if (summary & GpgME::Signature::Red) {
                 if (result2.isEmpty()) {
                     // Note:
                     // Here we are work differently than KMail did before!
                     //
                     // The BAD case ( == sig *not* matching )
                     // by definition does *not* show any key
                     // information but just states that things are BAD.
                     //
                     // The reason for this: In this case ALL information
                     // might be falsificated, we can NOT trust the data
                     // in the body NOT the signature - so we don't show
                     // any key/signature information at all!
                     //         (khz, according to LinuxTag 2002 meeting)
                     showKeyInfos = false;
                 }
                 frameColor = SIG_FRAME_COL_RED;
             } else {
                 result.clear();
             }
 
             if (SIG_FRAME_COL_GREEN == frameColor) {
                 result = i18n("Good signature.");
             } else if (SIG_FRAME_COL_RED == frameColor) {
                 result = i18n("Bad signature.");
             } else {
                 result.clear();
             }
 
             if (!result2.isEmpty()) {
                 if (!result.isEmpty()) {
                     result.append(QLatin1String("<br />"));
                 }
                 result.append(result2);
             }
         }
         /*
         // add i18n support for 3rd party plug-ins here:
         else if ( cryptPlug->libName().contains( "yetanotherpluginname", Qt::CaseInsensitive )) {
 
         }
         */
     }
     return result;
 }
 
 /** Checks whether @p str contains external references. To be precise,
     we only check whether @p str contains 'xxx="http[s]:' where xxx is
     not href. Obfuscated external references are ignored on purpose.
 */
 
 bool containsExternalReferences(const QString &str, const QString &extraHead)
 {
     const bool hasBaseInHeader = extraHead.contains(QStringLiteral(
                                                         "<base href=\""), Qt::CaseInsensitive);
     if (hasBaseInHeader && (str.contains(QStringLiteral("href=\"/"), Qt::CaseInsensitive)
                             || str.contains(QStringLiteral("<img src=\"/"), Qt::CaseInsensitive))) {
         return true;
     }
     int httpPos = str.indexOf(QLatin1String("\"http:"), Qt::CaseInsensitive);
     int httpsPos = str.indexOf(QLatin1String("\"https:"), Qt::CaseInsensitive);
 
     while (httpPos >= 0 || httpsPos >= 0) {
         // pos = index of next occurrence of "http: or "https: whichever comes first
         int pos = (httpPos < httpsPos)
                   ? ((httpPos >= 0) ? httpPos : httpsPos)
                   : ((httpsPos >= 0) ? httpsPos : httpPos);
         // look backwards for "href"
         if (pos > 5) {
             int hrefPos = str.lastIndexOf(QLatin1String("href"), pos - 5, Qt::CaseInsensitive);
             // if no 'href' is found or the distance between 'href' and '"http[s]:'
             // is larger than 7 (7 is the distance in 'href = "http[s]:') then
             // we assume that we have found an external reference
             if ((hrefPos == -1) || (pos - hrefPos > 7)) {
                 // HTML messages created by KMail itself for now contain the following:
                 // <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
                 // Make sure not to show an external references warning for this string
                 int dtdPos = str.indexOf(QLatin1String(
                                              "http://www.w3.org/TR/html4/loose.dtd"), pos + 1);
                 if (dtdPos != (pos + 1)) {
                     return true;
                 }
             }
         }
         // find next occurrence of "http: or "https:
         if (pos == httpPos) {
             httpPos = str.indexOf(QLatin1String("\"http:"), httpPos + 6, Qt::CaseInsensitive);
         } else {
             httpsPos = str.indexOf(QLatin1String("\"https:"), httpsPos + 7, Qt::CaseInsensitive);
         }
     }
     return false;
 }
 
 // FIXME this used to go through the full webkit parser to extract the body and head blocks
 // until we have that back, at least attempt to fix some of the damage
 // yes, "parsing" HTML with regexps is very very wrong, but it's still better than not filtering
 // this at all...
 QString processHtml(const QString &htmlSource, QString &extraHead)
 {
     auto s = htmlSource.trimmed();
     s = s.replace(QRegExp(QStringLiteral("^<!DOCTYPE[^>]*>"), Qt::CaseInsensitive), QString()).trimmed();
     s = s.replace(QRegExp(QStringLiteral("^<html[^>]*>"), Qt::CaseInsensitive), QString()).trimmed();
 
     // head
     s = s.replace(QRegExp(QStringLiteral("^<head/>"), Qt::CaseInsensitive), QString()).trimmed();
     if (s.startsWith(QLatin1String("<head>", Qt::CaseInsensitive))) {
         const auto idx = s.indexOf(QLatin1String("</head>"), Qt::CaseInsensitive);
         if (idx < 0) {
             return htmlSource;
         }
         extraHead = s.mid(6, idx - 6);
         s = s.mid(idx + 7).trimmed();
     }
 
     // body
     s = s.replace(QRegExp(QStringLiteral("<body[^>]*>"), Qt::CaseInsensitive), QString()).trimmed();
     s = s.replace(QRegExp(QStringLiteral("</html>$"), Qt::CaseInsensitive), QString()).trimmed();
     s = s.replace(QRegExp(QStringLiteral("</body>$"), Qt::CaseInsensitive), QString()).trimmed();
     return s;
 }
 
 DefaultRendererPrivate::DefaultRendererPrivate(const MessagePart::Ptr &msgPart, CSSHelperBase *cssHelper, HtmlWriter *writer, const MessagePartRendererFactory *rendererFactory)
     : mMsgPart(msgPart)
     , mCSSHelper(cssHelper)
     , mRendererFactory(rendererFactory)
 {
     renderFactory(mMsgPart, writer);
 }
 
 DefaultRendererPrivate::~DefaultRendererPrivate()
 {
 }
 
 CSSHelperBase *DefaultRendererPrivate::cssHelper() const
 {
     return mCSSHelper;
 }
 
 Interface::ObjectTreeSource *DefaultRendererPrivate::source() const
 {
     return mMsgPart->source();
 }
 
 void DefaultRendererPrivate::renderSubParts(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter)
 {
     foreach (const auto &m, msgPart->subParts()) {
         renderFactory(m, htmlWriter);
     }
 }
 
 void DefaultRendererPrivate::render(const MessagePartList::Ptr &mp, HtmlWriter *htmlWriter)
 {
     HTMLBlock::Ptr rBlock;
     HTMLBlock::Ptr aBlock;
 
     if (mp->isRoot()) {
         rBlock = HTMLBlock::Ptr(new RootBlock(htmlWriter));
     }
 
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
 
     renderSubParts(mp, htmlWriter);
 }
 
 void DefaultRendererPrivate::render(const MimeMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     HTMLBlock::Ptr aBlock;
     HTMLBlock::Ptr rBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
 
     if (mp->isRoot()) {
         rBlock = HTMLBlock::Ptr(new RootBlock(htmlWriter));
     }
 
     renderSubParts(mp, htmlWriter);
 }
 
 void DefaultRendererPrivate::render(const EncapsulatedRfc822MessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     if (!mp->hasSubParts()) {
         return;
     }
     Grantlee::Template t = MessagePartRendererManager::self()->loadByName(QStringLiteral(":/encapsulatedrfc822messagepart.html"));
     Grantlee::Context c = MessagePartRendererManager::self()->createContext();
     QObject block;
 
     c.insert(QStringLiteral("block"), &block);
     block.setProperty("link",
                       mp->nodeHelper()->asHREF(mp->mMessage.data(), QStringLiteral("body")));
 
     c.insert(QStringLiteral("msgHeader"), mp->source()->createMessageHeader(mp->mMessage.data()));
     c.insert(QStringLiteral("content"), QVariant::fromValue<GrantleeCallback>([this, mp, htmlWriter](Grantlee::OutputStream *) {
         renderSubParts(mp, htmlWriter);
     }));
 
     HTMLBlock::Ptr aBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
 }
 
 void DefaultRendererPrivate::render(const HtmlMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     Grantlee::Template t = MessageViewer::MessagePartRendererManager::self()->loadByName(QStringLiteral(
                                                                                              ":/htmlmessagepart.html"));
     Grantlee::Context c = MessageViewer::MessagePartRendererManager::self()->createContext();
     QObject block;
 
     c.insert(QStringLiteral("block"), &block);
 
     auto preferredMode = mp->source()->preferredMode();
     bool isHtmlPreferred = (preferredMode == Util::Html) || (preferredMode == Util::MultipartHtml);
     const bool isPrinting = mp->source()->isPrinting();
     block.setProperty("htmlMail", isHtmlPreferred);
     block.setProperty("loadExternal", mp->source()->htmlLoadExternal());
     block.setProperty("isPrinting", isPrinting);
     {
         QString extraHead;
         //laurent: FIXME port to async method webengine
         QString bodyText = processHtml(mp->mBodyHTML, extraHead);
 
         if (isHtmlPreferred) {
             mp->nodeHelper()->setNodeDisplayedEmbedded(mp->content(), true);
             htmlWriter->extraHead(extraHead);
         }
 
         block.setProperty("containsExternalReferences",
                           containsExternalReferences(bodyText, extraHead));
         c.insert(QStringLiteral("content"), bodyText);
     }
 
     {
         ConvertHtmlToPlainText convert;
         convert.setHtmlString(mp->mBodyHTML);
         QString plaintext = convert.generatePlainText();
         plaintext.replace(QLatin1Char('\n'), QStringLiteral("<br>"));
         c.insert(QStringLiteral("plaintext"), plaintext);
     }
     mp->source()->setHtmlMode(Util::Html, QList<Util::HtmlMode>() << Util::Html);
 
     HTMLBlock::Ptr aBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
 }
 
 void DefaultRendererPrivate::renderEncrypted(const EncryptedMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     KMime::Content *node = mp->content();
     const auto metaData = *mp->partMetaData();
 
     Grantlee::Template t = MessageViewer::MessagePartRendererManager::self()->loadByName(QStringLiteral(
                                                                                              ":/encryptedmessagepart.html"));
     Grantlee::Context c = MessageViewer::MessagePartRendererManager::self()->createContext();
     QObject block;
 
     if (node || mp->hasSubParts()) {
         c.insert(QStringLiteral("content"), QVariant::fromValue<GrantleeCallback>([this, mp, htmlWriter](Grantlee::OutputStream *) {
             HTMLBlock::Ptr rBlock;
             if (mp->content() && mp->isRoot()) {
                 rBlock = HTMLBlock::Ptr(new RootBlock(htmlWriter));
             }
             renderSubParts(mp, htmlWriter);
         }));
     } else if (!metaData.inProgress) {
         c.insert(QStringLiteral("content"), QVariant::fromValue<GrantleeCallback>([this, mp, htmlWriter](Grantlee::OutputStream *) {
-            renderWithFactory(QStringLiteral("MimeTreeParser::MessagePart"), mp, htmlWriter);
+            renderWithFactory<MimeTreeParser::MessagePart>(mp, htmlWriter);
         }));
     }
 
     c.insert(QStringLiteral("cryptoProto"), QVariant::fromValue(mp->mCryptoProto));
     if (mp->mDecryptRecipients.size() > 0) {
         c.insert(QStringLiteral("decryptedRecipients"),
                  QVariant::fromValue(mp->mDecryptRecipients));
     }
     c.insert(QStringLiteral("block"), &block);
 
     block.setProperty("inProgress", metaData.inProgress);
     block.setProperty("isDecrypted", mp->decryptMessage());
     block.setProperty("isDecryptable", metaData.isDecryptable);
     block.setProperty("decryptIcon",
                       QUrl::fromLocalFile(IconNameCache::instance()->iconPath(QStringLiteral(
                                                                                   "document-decrypt"),
                                                                               KIconLoader::Small)).url());
     block.setProperty("errorText", metaData.errorText);
     block.setProperty("noSecKey", mp->mNoSecKey);
 
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
 }
 
 void DefaultRendererPrivate::renderSigned(const SignedMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     KMime::Content *node = mp->content();
     const auto metaData = *mp->partMetaData();
     auto cryptoProto = mp->mCryptoProto;
 
     const bool isSMIME = cryptoProto && (cryptoProto == QGpgME::smime());
 
     Grantlee::Template t = MessageViewer::MessagePartRendererManager::self()->loadByName(QStringLiteral(
                                                                                              ":/signedmessagepart.html"));
     Grantlee::Context c = MessageViewer::MessagePartRendererManager::self()->createContext();
     QObject block;
 
     if (node) {
         c.insert(QStringLiteral("content"), QVariant::fromValue<GrantleeCallback>([this, mp, htmlWriter](Grantlee::OutputStream *) {
             HTMLBlock::Ptr rBlock;
             if (mp->isRoot()) {
                 rBlock = HTMLBlock::Ptr(new RootBlock(htmlWriter));
             }
             renderSubParts(mp, htmlWriter);
         }));
     } else if (!metaData.inProgress) {
         c.insert(QStringLiteral("content"), QVariant::fromValue<GrantleeCallback>([this, mp, htmlWriter](Grantlee::OutputStream *) {
-            renderWithFactory(QStringLiteral("MimeTreeParser::MessagePart"), mp, htmlWriter);
+            renderWithFactory<MimeTreeParser::MessagePart>(mp, htmlWriter);
         }));
     }
 
     c.insert(QStringLiteral("cryptoProto"), QVariant::fromValue(cryptoProto));
     c.insert(QStringLiteral("block"), &block);
 
     block.setProperty("inProgress", metaData.inProgress);
     block.setProperty("errorText", metaData.errorText);
 
     block.setProperty("detailHeader", mp->source()->showSignatureDetails());
     block.setProperty("printing", false);
     block.setProperty("addr", metaData.signerMailAddresses.join(QLatin1Char(',')));
     block.setProperty("technicalProblem", metaData.technicalProblem);
     block.setProperty("keyId", metaData.keyId);
     if (metaData.creationTime.isValid()) {      //should be handled inside grantlee but currently not possible see: https://bugs.kde.org/363475
         block.setProperty("creationTime",
                           QLocale().toString(metaData.creationTime, QLocale::ShortFormat));
     }
     block.setProperty("isGoodSignature", metaData.isGoodSignature);
     block.setProperty("isSMIME", isSMIME);
 
     if (metaData.keyTrust == GpgME::Signature::Unknown) {
         block.setProperty("keyTrust", QStringLiteral("unknown"));
     } else if (metaData.keyTrust == GpgME::Signature::Marginal) {
         block.setProperty("keyTrust", QStringLiteral("marginal"));
     } else if (metaData.keyTrust == GpgME::Signature::Full) {
         block.setProperty("keyTrust", QStringLiteral("full"));
     } else if (metaData.keyTrust == GpgME::Signature::Ultimate) {
         block.setProperty("keyTrust", QStringLiteral("ultimate"));
     } else {
         block.setProperty("keyTrust", QStringLiteral("untrusted"));
     }
 
     QString startKeyHREF;
     {
         QString keyWithWithoutURL;
         if (cryptoProto) {
             startKeyHREF
                 = QStringLiteral("<a href=\"kmail:showCertificate#%1 ### %2 ### %3\">")
                   .arg(cryptoProto->displayName(),
                        cryptoProto->name(),
                        QString::fromLatin1(metaData.keyId));
 
             keyWithWithoutURL
                 = QStringLiteral("%1%2</a>").arg(startKeyHREF,
                                                  QString::fromLatin1(QByteArray(QByteArrayLiteral(
                                                                                     "0x")
                                                                                 + metaData.keyId)));
         } else {
             keyWithWithoutURL = QStringLiteral("0x") + QString::fromUtf8(metaData.keyId);
         }
         block.setProperty("keyWithWithoutURL", keyWithWithoutURL);
     }
 
     bool onlyShowKeyURL = false;
     bool showKeyInfos = false;
     bool cannotCheckSignature = true;
     QString signer = metaData.signer;
     QString statusStr;
     QString mClass;
     QString greenCaseWarning;
 
     if (metaData.inProgress) {
         mClass = QStringLiteral("signInProgress");
     } else {
         const QStringList &blockAddrs(metaData.signerMailAddresses);
         // note: At the moment frameColor and showKeyInfos are
         //       used for CMS only but not for PGP signatures
         // pending(khz): Implement usage of these for PGP sigs as well.
         int frameColor = SIG_FRAME_COL_UNDEF;
         statusStr = sigStatusToString(cryptoProto,
                                       metaData.status_code,
                                       metaData.sigSummary,
                                       frameColor,
                                       showKeyInfos);
         // if needed fallback to english status text
         // that was reported by the plugin
         if (statusStr.isEmpty()) {
             statusStr = metaData.status;
         }
         if (metaData.technicalProblem) {
             frameColor = SIG_FRAME_COL_YELLOW;
         }
 
         switch (frameColor) {
         case SIG_FRAME_COL_RED:
             cannotCheckSignature = false;
             break;
         case SIG_FRAME_COL_YELLOW:
             cannotCheckSignature = true;
             break;
         case SIG_FRAME_COL_GREEN:
             cannotCheckSignature = false;
             break;
         }
 
         // temporary hack: always show key information!
         showKeyInfos = true;
 
         if (isSMIME && (SIG_FRAME_COL_UNDEF != frameColor)) {
             switch (frameColor) {
             case SIG_FRAME_COL_RED:
                 mClass = QStringLiteral("signErr");
                 onlyShowKeyURL = true;
                 break;
             case SIG_FRAME_COL_YELLOW:
                 if (metaData.technicalProblem) {
                     mClass = QStringLiteral("signWarn");
                 } else {
                     mClass = QStringLiteral("signOkKeyBad");
                 }
                 break;
             case SIG_FRAME_COL_GREEN:
                 mClass = QStringLiteral("signOkKeyOk");
                 // extra hint for green case
                 // that email addresses in DN do not match fromAddress
                 QString msgFrom(KEmailAddress::extractEmailAddress(mp->mFromAddress));
                 QString certificate;
                 if (metaData.keyId.isEmpty()) {
                     certificate = i18n("certificate");
                 } else {
                     certificate = startKeyHREF + i18n("certificate") + QStringLiteral("</a>");
                 }
 
                 if (!blockAddrs.empty()) {
                     if (!blockAddrs.contains(msgFrom, Qt::CaseInsensitive)) {
                         greenCaseWarning
                             = QStringLiteral("<u>")
                               +i18nc("Start of warning message.", "Warning:")
                               +QStringLiteral("</u> ")
                               +i18n(
                             "Sender's mail address is not stored in the %1 used for signing.",
                             certificate)
                               +QStringLiteral("<br />")
                               +i18n("sender: ")
                               +msgFrom
                               +QStringLiteral("<br />")
                               +i18n("stored: ");
                         // We cannot use Qt's join() function here but
                         // have to join the addresses manually to
                         // extract the mail addresses (without '<''>')
                         // before including it into our string:
                         bool bStart = true;
                         QStringList::ConstIterator end(blockAddrs.constEnd());
                         for (QStringList::ConstIterator it = blockAddrs.constBegin();
                              it != end; ++it) {
                             if (!bStart) {
                                 greenCaseWarning.append(QStringLiteral(", <br />&nbsp; &nbsp;"));
                             }
 
                             bStart = false;
                             greenCaseWarning.append(KEmailAddress::extractEmailAddress(*it));
                         }
                     }
                 } else {
                     greenCaseWarning
                         = QStringLiteral("<u>")
                           +i18nc("Start of warning message.", "Warning:")
                           +QStringLiteral("</u> ")
                           +i18n("No mail address is stored in the %1 used for signing, "
                                 "so we cannot compare it to the sender's address %2.",
                                 certificate,
                                 msgFrom);
                 }
                 break;
             }
 
             if (showKeyInfos && !cannotCheckSignature) {
                 if (metaData.signer.isEmpty()) {
                     signer.clear();
                 } else {
                     if (!blockAddrs.empty()) {
                         const QUrl address = KEmailAddress::encodeMailtoUrl(blockAddrs.first());
                         signer
                             = QStringLiteral("<a href=\"mailto:%1\">%2</a>").arg(QLatin1String(QUrl
                                                                                                ::
                                                                                                toPercentEncoding(
                                                                                                    address
                                                                                                    .
                                                                                                    path())),
                                                                                  signer);
                     }
                 }
             }
         } else {
             if (metaData.signer.isEmpty() || metaData.technicalProblem) {
                 mClass = QStringLiteral("signWarn");
             } else {
                 // HTMLize the signer's user id and create mailto: link
                 signer = MessageCore::StringUtil::quoteHtmlChars(signer, true);
                 signer = QStringLiteral("<a href=\"mailto:%1\">%1</a>").arg(signer);
 
                 if (metaData.isGoodSignature) {
                     if (metaData.keyTrust < GpgME::Signature::Marginal) {
                         mClass = QStringLiteral("signOkKeyBad");
                     } else {
                         mClass = QStringLiteral("signOkKeyOk");
                     }
                 } else {
                     mClass = QStringLiteral("signErr");
                 }
             }
         }
     }
 
     block.setProperty("onlyShowKeyURL", onlyShowKeyURL);
     block.setProperty("showKeyInfos", showKeyInfos);
     block.setProperty("cannotCheckSignature", cannotCheckSignature);
     block.setProperty("signer", signer);
     block.setProperty("statusStr", statusStr);
     block.setProperty("signClass", mClass);
     block.setProperty("greenCaseWarning", greenCaseWarning);
 
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
 }
 
 void DefaultRendererPrivate::render(const SignedMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     const auto metaData = *mp->partMetaData();
     if (metaData.isSigned || metaData.inProgress) {
         HTMLBlock::Ptr aBlock;
         if (mp->isAttachment()) {
             aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
         }
         renderSigned(mp, htmlWriter);
         return;
     }
 
     HTMLBlock::Ptr aBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
     if (mp->hasSubParts()) {
         renderSubParts(mp, htmlWriter);
     } else if (!metaData.inProgress) {
-        renderWithFactory(QStringLiteral("MimeTreeParser::MessagePart"), mp, htmlWriter);
+        renderWithFactory<MimeTreeParser::MessagePart>(mp, htmlWriter);
     }
 }
 
 void DefaultRendererPrivate::render(const EncryptedMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     const auto metaData = *mp->partMetaData();
 
     if (metaData.isEncrypted || metaData.inProgress) {
         HTMLBlock::Ptr aBlock;
         if (mp->isAttachment()) {
             aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
         }
         renderEncrypted(mp, htmlWriter);
         return;
     }
 
     HTMLBlock::Ptr aBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
 
     if (mp->hasSubParts()) {
         renderSubParts(mp, htmlWriter);
     } else if (!metaData.inProgress) {
-        renderWithFactory(QStringLiteral("MimeTreeParser::MessagePart"), mp, htmlWriter);
+        renderWithFactory<MimeTreeParser::MessagePart>(mp, htmlWriter);
     }
 }
 
 void DefaultRendererPrivate::render(const AlternativeMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     HTMLBlock::Ptr aBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
 
     auto mode = mp->preferredMode();
     if (mode == MimeTreeParser::Util::MultipartPlain && mp->text().trimmed().isEmpty()) {
         foreach (const auto m, mp->availableModes()) {
             if (m != MimeTreeParser::Util::MultipartPlain) {
                 mode = m;
                 break;
             }
         }
     }
     MimeMessagePart::Ptr part(mp->mChildParts.first());
     if (mp->mChildParts.contains(mode)) {
         part = mp->mChildParts[mode];
     }
 
     render(part, htmlWriter);
 }
 
 void DefaultRendererPrivate::render(const CertMessagePart::Ptr &mp, HtmlWriter *htmlWriter)
 {
     const GpgME::ImportResult &importResult(mp->mImportResult);
     Grantlee::Template t = MessageViewer::MessagePartRendererManager::self()->loadByName(QStringLiteral(
                                                                                              ":/certmessagepart.html"));
     Grantlee::Context c = MessageViewer::MessagePartRendererManager::self()->createContext();
     QObject block;
 
     c.insert(QStringLiteral("block"), &block);
     block.setProperty("importError", QString::fromLocal8Bit(importResult.error().asString()));
     block.setProperty("nImp", importResult.numImported());
     block.setProperty("nUnc", importResult.numUnchanged());
     block.setProperty("nSKImp", importResult.numSecretKeysImported());
     block.setProperty("nSKUnc", importResult.numSecretKeysUnchanged());
 
     QVariantList keylist;
     const auto imports = importResult.imports();
 
     auto end(imports.end());
     for (auto it = imports.begin(); it != end; ++it) {
         QObject *key(new QObject(mp.data()));
         key->setProperty("error", QString::fromLocal8Bit((*it).error().asString()));
         key->setProperty("status", (*it).status());
         key->setProperty("fingerprint", QLatin1String((*it).fingerprint()));
         keylist << QVariant::fromValue(key);
     }
 
     HTMLBlock::Ptr aBlock;
     if (mp->isAttachment()) {
         aBlock = HTMLBlock::Ptr(new AttachmentMarkBlock(htmlWriter, mp->attachmentContent()));
     }
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
 }
 
-bool DefaultRendererPrivate::renderWithFactory(const QString &className, const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter)
+bool DefaultRendererPrivate::renderWithFactory(const QMetaObject *mo, const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter)
 {
     if (!mRendererFactory) {
         return false;
     }
-    for (auto r : mRendererFactory->typeRegistry(className)) {
+    for (auto r : mRendererFactory->renderersForPart(mo, msgPart)) {
         if (r->render(msgPart, htmlWriter, this)) {
             return true;
         }
     }
     return false;
 }
 
 void DefaultRendererPrivate::renderFactory(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter)
 {
     const QString className = QString::fromUtf8(msgPart->metaObject()->className());
 
-    if (renderWithFactory(className, msgPart, htmlWriter)) {
+    if (renderWithFactory(msgPart, htmlWriter)) {
         return;
     }
 
     if (className == QStringLiteral("MimeTreeParser::MessagePartList")) {
         auto mp = msgPart.dynamicCast<MessagePartList>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::MimeMessagePart")) {
         auto mp = msgPart.dynamicCast<MimeMessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::EncapsulatedRfc822MessagePart")) {
         auto mp = msgPart.dynamicCast<EncapsulatedRfc822MessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::HtmlMessagePart")) {
         auto mp = msgPart.dynamicCast<HtmlMessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::SignedMessagePart")) {
         auto mp = msgPart.dynamicCast<SignedMessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::EncryptedMessagePart")) {
         auto mp = msgPart.dynamicCast<EncryptedMessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::AlternativeMessagePart")) {
         auto mp = msgPart.dynamicCast<AlternativeMessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else if (className == QStringLiteral("MimeTreeParser::CertMessagePart")) {
         auto mp = msgPart.dynamicCast<CertMessagePart>();
         if (mp) {
             render(mp, htmlWriter);
         }
     } else {
         qCWarning(MESSAGEVIEWER_LOG) << "We got a unkonwn classname, using default behaviour for "
                                      << className;
     }
 }
 
 DefaultRenderer::DefaultRenderer(const MimeTreeParser::MessagePart::Ptr &msgPart, CSSHelperBase *cssHelper, MimeTreeParser::HtmlWriter *writer)
     : d(new MimeTreeParser::DefaultRendererPrivate(msgPart, cssHelper, writer, MessagePartRendererFactory::instance()))
 {
 }
 
 DefaultRenderer::~DefaultRenderer()
 {
     delete d;
 }
diff --git a/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h b/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h
index 641d11e0..acb8a6ae 100644
--- a/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h
+++ b/messageviewer/src/messagepartthemes/default/defaultrenderer_p.h
@@ -1,67 +1,68 @@
 /*
    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_DEFAULTRENDERER_P_H__
 #define __MESSAGEVIEWER_DEFAULTRENDERER_P_H__
 
 #include "defaultrenderer.h"
 #include "messagepartrendererbase.h"
 
 #include <MimeTreeParser/MessagePart>
 
 using namespace MimeTreeParser;
 using namespace MessageViewer;
 
 namespace MessageViewer {
 class MessagePartRendererFactory;
 class CSSHelperBase;
 class HtmlWriter;
 }
 
 namespace MimeTreeParser {
 class DefaultRendererPrivate : public MessageViewer::RenderContext
 {
 public:
     DefaultRendererPrivate(const MessagePart::Ptr &msgPart, CSSHelperBase *cssHelper, HtmlWriter *writer, const MessagePartRendererFactory *rendererFactory);
     ~DefaultRendererPrivate();
 
     CSSHelperBase *cssHelper() const override;
 
     Interface::ObjectTreeSource *source() const;
 
     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);
     void render(const EncapsulatedRfc822MessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     void render(const HtmlMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     void renderEncrypted(const EncryptedMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     void renderSigned(const SignedMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     void render(const SignedMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     void render(const EncryptedMessagePart::Ptr &mp, HtmlWriter *htmlWriter);
     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;
+    bool renderWithFactory(const QMetaObject *mo, const MessagePart::Ptr &msgPart, HtmlWriter *writer) override;
+    using RenderContext::renderWithFactory;
     void renderFactory(const MessagePart::Ptr &msgPart, HtmlWriter *htmlWriter);
 
     MessagePart::Ptr mMsgPart;
     CSSHelperBase *mCSSHelper = nullptr;
     const MessageViewer::MessagePartRendererFactory *mRendererFactory = nullptr;
 };
 }
 #endif
diff --git a/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h b/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h
index e17b8e95..f1776292 100644
--- a/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h
+++ b/messageviewer/src/messagepartthemes/default/messagepartrendererbase.h
@@ -1,68 +1,79 @@
 /*
     Copyright (c) 2017 Sandro Knauß <sknauss@kde.org>
 
     KMail 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.
 
     KMail 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
 
     In addition, as a special exception, the copyright holders give
     permission to link the code of this program with any edition of
     the Qt library by Trolltech AS, Norway (or with modified versions
     of Qt that use the same license as Qt), and distribute linked
     combinations including the two.  You must obey the GNU General
     Public License in all respects for all of the code used other than
     Qt.  If you modify this file, you may extend this exception to
     your version of the file, but you are not obligated to do so.  If
     you do not wish to do so, delete this exception statement from
     your version.
 */
 
 #ifndef __MESSAGEVIEWER_MESSAGEPARTRENDERERBASE_H__
 #define __MESSAGEVIEWER_MESSAGEPARTRENDERERBASE_H__
 
 #include "messageviewer_export.h"
 
+#include <MimeTreeParser/MessagePart>
+
 #include <memory>
 #include <map>
 
 #include <QSharedPointer>
 
 namespace MimeTreeParser {
 class HtmlWriter;
-class MessagePart;
-typedef QSharedPointer<MessagePart> MessagePartPtr;
 }
 
 namespace MessageViewer {
 class CSSHelperBase;
 
 class MESSAGEVIEWER_EXPORT RenderContext
 {
 public:
     virtual ~RenderContext();
 
     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;
+    template <typename T>
+    inline bool renderWithFactory(const MimeTreeParser::MessagePart::Ptr &msgPart, MimeTreeParser::HtmlWriter *writer)
+    {
+        return renderWithFactory(&T::staticMetaObject, msgPart, writer);
+    }
+    inline bool renderWithFactory(const MimeTreeParser::MessagePart::Ptr &msgPart, MimeTreeParser::HtmlWriter *writer)
+    {
+        return renderWithFactory(msgPart->metaObject(), msgPart, writer);
+    }
+    virtual void renderSubParts(const MimeTreeParser::MessagePart::Ptr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter) = 0;
+
+protected:
+    virtual bool renderWithFactory(const QMetaObject *mo, const MimeTreeParser::MessagePart::Ptr &msgPart, MimeTreeParser::HtmlWriter *writer) = 0;
 };
 
 class MESSAGEVIEWER_EXPORT MessagePartRendererBase
 {
 public:
     MessagePartRendererBase();
     virtual ~MessagePartRendererBase();
-    virtual bool render(const MimeTreeParser::MessagePartPtr &, MimeTreeParser::HtmlWriter *htmlWriter, RenderContext *context)
+    virtual bool render(const MimeTreeParser::MessagePart::Ptr &, MimeTreeParser::HtmlWriter *htmlWriter, RenderContext *context)
     const = 0;
 };
 }
 #endif
diff --git a/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.cpp b/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.cpp
index 986c917b..ae8d9cd5 100644
--- a/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.cpp
+++ b/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.cpp
@@ -1,131 +1,177 @@
 /*
     This file is part of KMail, the KDE mail client.
     Copyright (c) 2017 Sandro Knauß <sknauss@kde.org>
 
     KMail 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.
 
     KMail 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
 
     In addition, as a special exception, the copyright holders give
     permission to link the code of this program with any edition of
     the Qt library by Trolltech AS, Norway (or with modified versions
     of Qt that use the same license as Qt), and distribute linked
     combinations including the two.  You must obey the GNU General
     Public License in all respects for all of the code used other than
     Qt.  If you modify this file, you may extend this exception to
     your version of the file, but you are not obligated to do so.  If
     you do not wish to do so, delete this exception statement from
     your version.
 */
 
 #include "messagepartrendererfactory.h"
 #include "messagepartrendererfactory_p.h"
 #include "messagepartrenderplugin.h"
 #include "viewer/urlhandlermanager.h"
 
 #include "messagepartrendererbase.h"
 #include "messageviewer_debug.h"
 
 #include "plugins/attachmentmessagepartrenderer.h"
 #include "plugins/messagepartrenderer.h"
 #include "plugins/textmessagepartrenderer.h"
 
 #include <KPluginLoader>
 
 #include <QJsonArray>
 #include <QJsonObject>
+#include <QMimeDatabase>
+#include <QMimeType>
+
+#include <algorithm>
 
 using namespace MessageViewer;
 
 void MessagePartRendererFactoryPrivate::setup()
 {
-    if (mAll.isEmpty()) {
+    if (m_renderers.isEmpty()) {
         initalize_builtin_renderers();
         loadPlugins();
     }
+    Q_ASSERT(!m_renderers.isEmpty());
 }
 
 void MessagePartRendererFactoryPrivate::loadPlugins()
 {
     KPluginLoader::forEachPlugin(QStringLiteral("messageviewer/bodypartformatter"), [this](const QString &path) {
         QPluginLoader loader(path);
         const auto pluginData = loader.metaData().value(QLatin1String("MetaData")).toObject().value(QLatin1String("renderer")).toArray();
         if (pluginData.isEmpty()) {
             qCWarning(MESSAGEVIEWER_LOG) << "Plugin" << path << "has no meta data.";
             return;
         }
 
         auto plugin = qobject_cast<MessagePartRenderPlugin *>(loader.instance());
         if (!plugin) {
             qCWarning(MESSAGEVIEWER_LOG) << path << "is not a MessagePartRendererPlugin";
             return;
         }
 
         MessagePartRendererBase *renderer = nullptr;
         for (int i = 0; (renderer = plugin->renderer(i)) && i < pluginData.size(); ++i) {
             const auto metaData = pluginData.at(i).toObject();
-            const auto type = metaData.value(QLatin1String("type")).toString();
+            const auto type = metaData.value(QLatin1String("type")).toString().toUtf8();
             if (type.isEmpty()) {
                 qCWarning(MESSAGEVIEWER_LOG) << path << "returned empty type specification for index" << i;
                 break;
             }
-            // TODO add plugin priority like we have for BPFs
-            qCDebug(MESSAGEVIEWER_LOG) << "renderer plugin for " << type;
-            insert(type, renderer /*, priority*/);
+            const auto mimetype = metaData.value(QLatin1String("mimetype")).toString().toLower();
+            // priority should always be higher than the built-in ones, otherwise what's the point?
+            const auto priority = metaData.value(QLatin1String("priority")).toInt() + 100;
+            qCDebug(MESSAGEVIEWER_LOG) << "renderer plugin for " << type << mimetype << priority;
+            insert(type, renderer, mimetype, priority);
         }
 
         const Interface::BodyPartURLHandler *handler = nullptr;
         for (int i = 0; (handler = plugin->urlHandler(i)); ++i) {
             URLHandlerManager::instance()->registerHandler(handler);
         }
     });
 }
 
 void MessagePartRendererFactoryPrivate::initalize_builtin_renderers()
 {
-    insert(QStringLiteral("MimeTreeParser::MessagePart"), new MessagePartRenderer());
-    insert(QStringLiteral("MimeTreeParser::TextMessagePart"), new TextMessagePartRenderer());
-    insert(QStringLiteral("MimeTreeParser::AttachmentMessagePart"), new AttachmentMessagePartRenderer());
+    insert("MimeTreeParser::MessagePart", new MessagePartRenderer());
+    insert("MimeTreeParser::TextMessagePart", new TextMessagePartRenderer());
+    insert("MimeTreeParser::AttachmentMessagePart", new AttachmentMessagePartRenderer());
 }
 
-void MessagePartRendererFactoryPrivate::insert(const QString &type, MessagePartRendererBase *formatter)
+void MessagePartRendererFactoryPrivate::insert(const QByteArray &type, MessagePartRendererBase *renderer, const QString &mimeType, int priority)
 {
-    if (type.isEmpty() || !formatter) {
+    if (type.isEmpty() || !renderer) {
         return;
     }
 
-    mAll[type].insert(mAll[type].begin(), formatter);
+    QMimeDatabase db;
+    const auto mt = db.mimeTypeForName(mimeType);
+
+    RendererInfo info;
+    info.renderer = renderer;
+    info.mimeType = mt.isValid() ? mt.name() : mimeType;
+    info.priority = priority;
+
+    auto &v = m_renderers[type];
+    v.push_back(info);
 }
 
 MessagePartRendererFactory::MessagePartRendererFactory()
     : d(new MessagePartRendererFactoryPrivate)
 {
 }
 
 MessagePartRendererFactory::~MessagePartRendererFactory()
 {
 }
 
 MessagePartRendererFactory *MessagePartRendererFactory::instance()
 {
-    static std::unique_ptr<MessagePartRendererFactory> singeltonRendererFactory(new MessagePartRendererFactory);
-    return singeltonRendererFactory.get();
+    static MessagePartRendererFactory s_instance;
+    return &s_instance;
 }
 
-std::vector<MessagePartRendererBase *> MessagePartRendererFactory::typeRegistry(
-    const QString &type) const
+QVector<MessagePartRendererBase*> MessagePartRendererFactory::renderersForPart(const QMetaObject *mo, const MimeTreeParser::MessagePartPtr &mp) const
 {
     d->setup();
-    Q_ASSERT(!d->mAll.isEmpty());
-    return d->mAll.value(type);
+
+    const auto mtName = mp->content() ? QString::fromUtf8(mp->content()->contentType()->mimeType().toLower()) : QString();
+    QMimeDatabase db;
+    const auto mt = db.mimeTypeForName(mtName);
+    auto ancestors = mt.allAncestors();
+    if (mt.isValid() || !mtName.isEmpty())
+        ancestors.prepend(mt.isValid() ? mt.name() : mtName);
+
+    auto candidates = d->m_renderers.value(mo->className());
+
+    // remove candidates with a mimetype set that don't match the mimetype of the part
+    candidates.erase(std::remove_if(candidates.begin(), candidates.end(), [ancestors](const RendererInfo &info) {
+        if (info.mimeType.isEmpty())
+            return false;
+        return !ancestors.contains(info.mimeType);
+    }), candidates.end());
+
+    // sort most specific mimetpypes first
+    std::stable_sort(candidates.begin(), candidates.end(), [ancestors](const RendererInfo &lhs, const RendererInfo &rhs) {
+        if (lhs.mimeType == rhs.mimeType)
+            return lhs.priority > rhs.priority;
+        if (lhs.mimeType.isEmpty())
+            return false;
+        if (rhs.mimeType.isEmpty())
+            return true;
+        return ancestors.indexOf(lhs.mimeType) < ancestors.indexOf(rhs.mimeType);
+    });
+
+    QVector<MessagePartRendererBase*> r;
+    for (const auto &candidate : candidates) {
+        r.push_back(candidate.renderer);
+    }
+    return r;
 }
diff --git a/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.h b/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.h
index 740ed10c..deed6e07 100644
--- a/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.h
+++ b/messageviewer/src/messagepartthemes/default/messagepartrendererfactory.h
@@ -1,63 +1,62 @@
 /*
     This file is part of KMail, the KDE mail client.
     Copyright (c) 2017 Sandro Knauß <sknauss@kde.org>
 
     KMail 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.
 
     KMail 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
 
     In addition, as a special exception, the copyright holders give
     permission to link the code of this program with any edition of
     the Qt library by Trolltech AS, Norway (or with modified versions
     of Qt that use the same license as Qt), and distribute linked
     combinations including the two.  You must obey the GNU General
     Public License in all respects for all of the code used other than
     Qt.  If you modify this file, you may extend this exception to
     your version of the file, but you are not obligated to do so.  If
     you do not wish to do so, delete this exception statement from
     your version.
 */
 
 #ifndef MESSAGEVIEWER_MESSAGEPARTRENDERERFACTORY_H
 #define MESSAGEVIEWER_MESSAGEPARTRENDERERFACTORY_H
 
 #include "messageviewer_export.h"
 
-#include <qglobal.h>
+#include <MimeTreeParser/MessagePart>
 
-#include <memory>
-#include <vector>
+#include <QVector>
 
-class QString;
+#include <memory>
 
 namespace MessageViewer {
 class MessagePartRendererBase;
 class MessagePartRendererFactoryPrivate;
 
 class MESSAGEVIEWER_EXPORT MessagePartRendererFactory
 {
 public:
     MessagePartRendererFactory();
     ~MessagePartRendererFactory();
 
     static MessagePartRendererFactory *instance();
 
-    std::vector<MessagePartRendererBase *> typeRegistry(const QString &type) const;
+    QVector<MessagePartRendererBase*> renderersForPart(const QMetaObject *mo, const MimeTreeParser::MessagePart::Ptr &mp) const;
 
 private:
     Q_DISABLE_COPY(MessagePartRendererFactory)
     std::unique_ptr<MessagePartRendererFactoryPrivate> d;
 };
 }
 
 #endif
diff --git a/messageviewer/src/messagepartthemes/default/messagepartrendererfactory_p.h b/messageviewer/src/messagepartthemes/default/messagepartrendererfactory_p.h
index 2a63a0ba..32c6df19 100644
--- a/messageviewer/src/messagepartthemes/default/messagepartrendererfactory_p.h
+++ b/messageviewer/src/messagepartthemes/default/messagepartrendererfactory_p.h
@@ -1,51 +1,60 @@
 /*
     Copyright (c) 2017 Sandro Knauß <sknauss@kde.org>
 
     KMail 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.
 
     KMail 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
 
     In addition, as a special exception, the copyright holders give
     permission to link the code of this program with any edition of
     the Qt library by Trolltech AS, Norway (or with modified versions
     of Qt that use the same license as Qt), and distribute linked
     combinations including the two.  You must obey the GNU General
     Public License in all respects for all of the code used other than
     Qt.  If you modify this file, you may extend this exception to
     your version of the file, but you are not obligated to do so.  If
     you do not wish to do so, delete this exception statement from
     your version.
 */
 
 #ifndef __MESSAGEVIEWER_MESSAGEPARTRENDERERBASEFACTORY_P_H__
 #define __MESSAGEVIEWER_MESSAGEPARTRENDERERBASEFACTORY_P_H__
 
-#include <QMap>
+#include <QByteArray>
+#include <QHash>
+#include <QString>
+
+#include <vector>
 
 namespace MessageViewer {
 class MessagePartRendererBase;
-typedef QMap<QString, std::vector<MessagePartRendererBase *> > TypeRegistry;
+
+struct RendererInfo {
+    MessagePartRendererBase *renderer;
+    QString mimeType;
+    int priority;
+};
 
 class MessagePartRendererFactoryPrivate
 {
 public:
     void setup();
     void loadPlugins();
-    void initalize_builtin_renderers();        //defined in pugins/plugins.cpp
-    void insert(const QString &type, MessagePartRendererBase *formatter);
+    void initalize_builtin_renderers();
+    void insert(const QByteArray &type, MessagePartRendererBase *formatter, const QString &mimeType = QString(), int priority = 0);
 
-    TypeRegistry mAll;
+    QHash<QByteArray, std::vector<RendererInfo>> m_renderers;
 };
 }
 
 #endif
diff --git a/messageviewer/src/messagepartthemes/default/plugins/attachmentmessagepartrenderer.cpp b/messageviewer/src/messagepartthemes/default/plugins/attachmentmessagepartrenderer.cpp
index b9ca39f0..2b509182 100644
--- a/messageviewer/src/messagepartthemes/default/plugins/attachmentmessagepartrenderer.cpp
+++ b/messageviewer/src/messagepartthemes/default/plugins/attachmentmessagepartrenderer.cpp
@@ -1,85 +1,85 @@
 /*
    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.
 */
 
 #include "attachmentmessagepartrenderer.h"
 
 #include "quotehtml.h"
 
 #include "utils/mimetype.h"
 #include "../defaultrenderer_p.h"
 #include "../messagepartrenderermanager.h"
 
 #include <MessageCore/StringUtil>
 #include <MimeTreeParser/HtmlWriter>
 
 #include <KIconLoader>
 #include <KLocalizedString>
 #include <QUrl>
 
 using namespace MessageViewer;
 
 AttachmentMessagePartRenderer::AttachmentMessagePartRenderer()
 {
 }
 
 AttachmentMessagePartRenderer::~AttachmentMessagePartRenderer()
 {
 }
 
 bool AttachmentMessagePartRenderer::render(const MimeTreeParser::MessagePartPtr &msgPart, MimeTreeParser::HtmlWriter *htmlWriter, RenderContext *context) const
 {
     auto mp = msgPart.dynamicCast<AttachmentMessagePart>();
     if (!mp) {
         return false;
     }
 
     KMime::Content *node = mp->content();
     if (mp->isHidden()) {
         return true;
     }
 
     const auto tmpAsIcon = mp->asIcon();
 
     if (tmpAsIcon == MimeTreeParser::NoIcon) {
-        return context->renderWithFactory(QStringLiteral("MimeTreeParser::TextMessagePart"), mp, htmlWriter);
+        return context->renderWithFactory<MimeTreeParser::TextMessagePart>(mp, htmlWriter);
     }
 
     Grantlee::Template t = MessageViewer::MessagePartRendererManager::self()->loadByName(QStringLiteral(
                                                                                              ":/asiconpart.html"));
     Grantlee::Context c = MessageViewer::MessagePartRendererManager::self()->createContext();
     c.insert(QStringLiteral("block"), msgPart.data());
 
     msgPart->setProperty("inline", (tmpAsIcon == MimeTreeParser::IconInline));
 
     QString iconPath;
     if (tmpAsIcon == MimeTreeParser::IconInline) {
         iconPath = mp->temporaryFilePath();
     } else {
         iconPath = MessageViewer::Util::iconPathForContent(node, KIconLoader::Desktop);
         if (iconPath.right(14) == QLatin1String("mime_empty.png")) {
             NodeHelper::magicSetType(node);
             iconPath = MessageViewer::Util::iconPathForContent(node, KIconLoader::Desktop);
         }
     }
     msgPart->setProperty("iconPath", QUrl::fromLocalFile(iconPath).url());
 
     Grantlee::OutputStream s(htmlWriter->stream());
     t->render(&s, &c);
     return true;
 }
diff --git a/mimetreeparser/src/viewer/messagepart.h b/mimetreeparser/src/viewer/messagepart.h
index bf8e0d9d..77bd533d 100644
--- a/mimetreeparser/src/viewer/messagepart.h
+++ b/mimetreeparser/src/viewer/messagepart.h
@@ -1,425 +1,422 @@
 /*
    Copyright (c) 2015 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 __MIMETREEPARSER_MESSAGEPART_H__
 #define __MIMETREEPARSER_MESSAGEPART_H__
 
 #include "mimetreeparser_export.h"
 
 #include "mimetreeparser/bodypartformatter.h"
 #include "mimetreeparser/util.h"
 
 #include <KMime/Message>
 
 #include <gpgme++/verificationresult.h>
 #include <gpgme++/decryptionresult.h>
 #include <gpgme++/importresult.h>
 
 #include <QString>
 #include <QSharedPointer>
 
 #include <memory>
 
 class QTextCodec;
-namespace MessageViewer {
-class AttachmentMessagePartRenderer;
-}
 
 namespace GpgME {
 class ImportResult;
 }
 
 namespace QGpgME {
 class Protocol;
 }
 
 namespace KMime {
 class Content;
 }
 
 namespace MimeTreeParser {
 class ObjectTreeParser;
 class CryptoBodyPartMemento;
 class MessagePartPrivate;
 class MultiPartAlternativeBodyPartFormatter;
 namespace Interface {
 class ObjectTreeSource;
 }
 
 class MIMETREEPARSER_EXPORT MessagePart : public QObject
 {
     Q_OBJECT
     Q_PROPERTY(QString plaintextContent READ plaintextContent)
     Q_PROPERTY(QString htmlContent READ htmlContent)
     Q_PROPERTY(bool isAttachment READ isAttachment)
     Q_PROPERTY(bool root READ isRoot)
     Q_PROPERTY(bool isHtml READ isHtml)
     Q_PROPERTY(bool isHidden READ isHidden)
     Q_PROPERTY(QString attachmentIndex READ attachmentIndex CONSTANT)
     Q_PROPERTY(QString link READ attachmentLink CONSTANT)
 public:
     typedef QSharedPointer<MessagePart> Ptr;
     MessagePart(ObjectTreeParser *otp, const QString &text);
     ~MessagePart();
 
     void setParentPart(MessagePart *parentPart);
     MessagePart *parentPart() const;
 
     virtual QString text() const;
     void setText(const QString &text);
 
     virtual QString plaintextContent() const;
     virtual QString htmlContent() const;
 
     /** The KMime::Content* node that's represented by this part.
      *  Can be @c nullptr, e.g. for sub-parts of an inline signed body part.
      */
     KMime::Content *content() const;
     void setContent(KMime::Content *node);
 
     /** The KMime::Content* node that's the source of this part.
      *  This is not necessarily the same as content(), for example for
      *  broken-up multipart nodes.
      */
     KMime::Content *attachmentContent() const;
     void setAttachmentContent(KMime::Content *node);
     bool isAttachment() const;
     /** @see KMime::Content::index() */
     QString attachmentIndex() const;
     /** @see NodeHelper::asHREF */
     QString attachmentLink() const;
 
     /** Returns a string respresentation of an URL that can be used
      *  to invoke a BodyPartURLHandler for this body part.
      */
     QString makeLink(const QString &path) const;
 
     void setIsRoot(bool root);
     bool isRoot() const;
 
     virtual bool isHtml() const;
     virtual bool isHidden() const;
 
     PartMetaData *partMetaData() const;
 
     Interface::BodyPartMemento *memento() const;
     void setMemento(Interface::BodyPartMemento *memento);
 
     /* only a function that should be removed if the refactoring is over */
     virtual void fix() const;
 
     void appendSubPart(const MessagePart::Ptr &messagePart);
     const QVector<MessagePart::Ptr> &subParts() const;
     bool hasSubParts() const;
 
     Interface::ObjectTreeSource *source() const;
     NodeHelper* nodeHelper() const;
 
 protected:
     void parseInternal(KMime::Content *node, bool onlyOneMimePart);
     QString renderInternalText() const;
 
     ObjectTreeParser *mOtp = nullptr;
 
 private:
     std::unique_ptr<MessagePartPrivate> d;
 };
 
 class MIMETREEPARSER_EXPORT MimeMessagePart : public MessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<MimeMessagePart> Ptr;
     MimeMessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, bool onlyOneMimePart);
     virtual ~MimeMessagePart();
 
     QString text() const override;
 
     QString plaintextContent() const override;
     QString htmlContent() const override;
 private:
     bool mOnlyOneMimePart;
 
     friend class AlternativeMessagePart;
 };
 
 class MIMETREEPARSER_EXPORT MessagePartList : public MessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<MessagePartList> Ptr;
     MessagePartList(MimeTreeParser::ObjectTreeParser *otp);
     virtual ~MessagePartList();
 
     QString text() const override;
 
     QString plaintextContent() const override;
     QString htmlContent() const override;
 };
 
 enum IconType {
     NoIcon = 0,
     IconExternal,
     IconInline
 };
 
 class MIMETREEPARSER_EXPORT TextMessagePart : public MessagePartList
 {
     Q_OBJECT
     Q_PROPERTY(bool showTextFrame READ showTextFrame CONSTANT)
     Q_PROPERTY(bool showLink READ showLink CONSTANT)
     Q_PROPERTY(QString label READ label CONSTANT)
     Q_PROPERTY(QString comment READ comment CONSTANT)
 public:
     typedef QSharedPointer<TextMessagePart> Ptr;
     TextMessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, bool drawFrame, bool decryptMessage);
     virtual ~TextMessagePart();
 
     KMMsgSignatureState signatureState() const;
     KMMsgEncryptionState encryptionState() const;
 
     bool decryptMessage() const;
 
     bool isHidden() const override;
 
     bool showLink() const;
     bool showTextFrame() const;
     void setShowTextFrame(bool showFrame);
 
     /** The attachment filename, or the closest approximation thereof we have. */
     QString label() const;
     /** A description of this attachment, if provided. */
     QString comment() const;
     /** Temporary file containing the part content. */
     QString temporaryFilePath() const;
 
 private:
     void parseContent();
 
     KMMsgSignatureState mSignatureState;
     KMMsgEncryptionState mEncryptionState;
     bool mDrawFrame;
     bool mDecryptMessage;
     bool mIsHidden;
 
     friend class ObjectTreeParser;
 };
 
 class MIMETREEPARSER_EXPORT AttachmentMessagePart : public TextMessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<AttachmentMessagePart> Ptr;
     AttachmentMessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, bool drawFrame, bool decryptMessage);
     virtual ~AttachmentMessagePart();
 
     IconType asIcon() const;
     bool neverDisplayInline() const;
     void setNeverDisplayInline(bool displayInline);
     bool isImage() const;
     void setIsImage(bool image);
 
     bool isHidden() const override;
 
 private:
     bool mIsImage;
     bool mNeverDisplayInline;
 };
 
 class MIMETREEPARSER_EXPORT HtmlMessagePart : public MessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<HtmlMessagePart> Ptr;
     HtmlMessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, MimeTreeParser::Interface::ObjectTreeSource *source);
     virtual ~HtmlMessagePart();
 
     QString text() const override;
 
     void fix() const override;
     bool isHtml() const override;
 
 private:
     Interface::ObjectTreeSource *mSource;
     QString mBodyHTML;
     QByteArray mCharset;
 
     friend class DefaultRendererPrivate;
 };
 
 class MIMETREEPARSER_EXPORT AlternativeMessagePart : public MessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<AlternativeMessagePart> Ptr;
     AlternativeMessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, Util::HtmlMode preferredMode);
     virtual ~AlternativeMessagePart();
 
     QString text() const override;
 
     Util::HtmlMode preferredMode() const;
 
     bool isHtml() const override;
 
     QString plaintextContent() const override;
     QString htmlContent() const override;
 
     QList<Util::HtmlMode> availableModes();
 
     void fix() const override;
 private:
     Util::HtmlMode mPreferredMode;
 
     QMap<Util::HtmlMode, KMime::Content *> mChildNodes;
     QMap<Util::HtmlMode, MimeMessagePart::Ptr> mChildParts;
 
     friend class DefaultRendererPrivate;
     friend class ObjectTreeParser;
     friend class MultiPartAlternativeBodyPartFormatter;
 };
 
 class MIMETREEPARSER_EXPORT CertMessagePart : public MessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<CertMessagePart> Ptr;
     CertMessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, const QGpgME::Protocol *cryptoProto, bool autoImport);
     virtual ~CertMessagePart();
 
     QString text() const override;
 
 private:
     bool mAutoImport;
     GpgME::ImportResult mImportResult;
     const QGpgME::Protocol *mCryptoProto;
     friend class DefaultRendererPrivate;
 };
 
 class MIMETREEPARSER_EXPORT EncapsulatedRfc822MessagePart : public MessagePart
 {
     Q_OBJECT
 public:
     typedef QSharedPointer<EncapsulatedRfc822MessagePart> Ptr;
     EncapsulatedRfc822MessagePart(MimeTreeParser::ObjectTreeParser *otp, KMime::Content *node, const KMime::Message::Ptr &message);
     virtual ~EncapsulatedRfc822MessagePart();
 
     QString text() const override;
 
     void fix() const override;
 private:
     const KMime::Message::Ptr mMessage;
 
     friend class DefaultRendererPrivate;
 };
 
 class MIMETREEPARSER_EXPORT EncryptedMessagePart : public MessagePart
 {
     Q_OBJECT
     Q_PROPERTY(bool decryptMessage READ decryptMessage WRITE setDecryptMessage)
     Q_PROPERTY(bool isEncrypted READ isEncrypted)
     Q_PROPERTY(bool passphraseError READ passphraseError)
 public:
     typedef QSharedPointer<EncryptedMessagePart> Ptr;
     EncryptedMessagePart(ObjectTreeParser *otp, const QString &text, const QGpgME::Protocol *cryptoProto, const QString &fromAddress, KMime::Content *node);
 
     virtual ~EncryptedMessagePart();
 
     QString text() const override;
 
     void setDecryptMessage(bool decrypt);
     bool decryptMessage() const;
 
     void setIsEncrypted(bool encrypted);
     bool isEncrypted() const;
 
     bool isDecryptable() const;
 
     bool passphraseError() const;
 
     void startDecryption(const QByteArray &text, const QTextCodec *aCodec);
     void startDecryption(KMime::Content *data = nullptr);
 
     QByteArray mDecryptedData;
 
     QString plaintextContent() const override;
     QString htmlContent() const override;
 
 private:
     /** Handles the dectyptioon of a given content
      * returns true if the decryption was successfull
      * if used in async mode, check if mMetaData.inProgress is true, it inicates a running decryption process.
      */
     bool okDecryptMIME(KMime::Content &data);
 
 protected:
     bool mPassphraseError;
     bool mNoSecKey;
     const QGpgME::Protocol *mCryptoProto;
     QString mFromAddress;
     bool mDecryptMessage;
     QByteArray mVerifiedText;
     std::vector<GpgME::DecryptionResult::Recipient> mDecryptRecipients;
 
     friend class DefaultRendererPrivate;
 };
 
 class MIMETREEPARSER_EXPORT SignedMessagePart : public MessagePart
 {
     Q_OBJECT
     Q_PROPERTY(bool isSigned READ isSigned)
 public:
     typedef QSharedPointer<SignedMessagePart> Ptr;
     SignedMessagePart(ObjectTreeParser *otp, const QString &text, const QGpgME::Protocol *cryptoProto, const QString &fromAddress, KMime::Content *node);
 
     virtual ~SignedMessagePart();
 
     void setIsSigned(bool isSigned);
     bool isSigned() const;
 
     void startVerification(const QByteArray &text, const QTextCodec *aCodec);
     void startVerificationDetached(const QByteArray &text, KMime::Content *textNode, const QByteArray &signature);
 
     QByteArray mDecryptedData;
     std::vector<GpgME::Signature> mSignatures;
 
     QString plaintextContent() const override;
     QString htmlContent() const override;
 
 private:
     /** Handles the verification of data
      * If signature is empty it is handled as inline signature otherwise as detached signature mode.
      * Returns true if the verfication was successfull and the block is signed.
      * If used in async mode, check if mMetaData.inProgress is true, it inicates a running verification process.
      */
     bool okVerify(const QByteArray &data, const QByteArray &signature, KMime::Content *textNode);
 
     void sigStatusToMetaData();
 
     void setVerificationResult(const CryptoBodyPartMemento *m, KMime::Content *textNode);
 protected:
     const QGpgME::Protocol *mCryptoProto;
     QString mFromAddress;
     QByteArray mVerifiedText;
 
     friend EncryptedMessagePart;
     friend class DefaultRendererPrivate;
 };
 }
 
 #endif //__MIMETREEPARSER_MESSAGEPART_H__