diff --git a/src/Cryptography/MessagePart.cpp b/src/Cryptography/MessagePart.cpp
index 2f35bff5..e5777848 100644
--- a/src/Cryptography/MessagePart.cpp
+++ b/src/Cryptography/MessagePart.cpp
@@ -1,550 +1,553 @@
 /* Copyright (C) 2014 - 2015 Stephan Platz <trojita@paalsteek.de>
    Copyright (C) 2006 - 2016 Jan Kundrát <jkt@kde.org>
 
    This file is part of the Trojita Qt IMAP e-mail client,
    http://trojita.flaska.net/
 
    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) version 3 or any later version
    accepted by the membership of KDE e.V. (or its successor approved
    by the membership of KDE e.V.), which shall act as a proxy
    defined in Section 14 of version 3 of the license.
 
    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, see <http://www.gnu.org/licenses/>.
 */
 
 #include <QtGui/QFont>
 
 #include "MessagePart.h"
 
 #include "MessageModel.h"
 #include "Cryptography/PartReplacer.h"
 #include "Common/MetaTypes.h"
 #include "Imap/Encoders.h"
 #include "Imap/Model/MailboxTree.h"
 #include "Imap/Model/ItemRoles.h"
 #include "UiUtils/Formatting.h"
 
 namespace Cryptography {
 
 #define PART_FETCH_CHILDREN(MODEL) const_cast<MessagePart *>(this)->fetchChildren(const_cast<MessageModel *>(MODEL))
 
 MessagePart::MessagePart(MessagePart *parent, const int row)
     : m_childrenState(FetchingState::NONE)
     , m_parent(parent)
     , m_children()
     , m_row(row)
 {
 }
 
 MessagePart::~MessagePart()
 {
 }
 
 MessagePart *MessagePart::parent() const
 {
     return m_parent;
 }
 
 int MessagePart::row() const
 {
     return m_row;
 }
 
 int MessagePart::rowCount(MessageModel *model) const
 {
     PART_FETCH_CHILDREN(model);
     return m_children.size();
 }
 
 int MessagePart::columnCount(MessageModel *model) const
 {
     PART_FETCH_CHILDREN(model);
     return 1;
 }
 
 MessagePart *MessagePart::child(MessageModel *model, int row, int column) const
 {
     PART_FETCH_CHILDREN(model);
     if (row == 0) {
         switch (column) {
         case Imap::Mailbox::TreeItem::OFFSET_HEADER:
             return m_headerPart.get();
         case Imap::Mailbox::TreeItem::OFFSET_TEXT:
             return m_textPart.get();
         case Imap::Mailbox::TreeItem::OFFSET_MIME:
             return m_mimePart.get();
         case Imap::Mailbox::TreeItem::OFFSET_RAW_CONTENTS:
             return m_rawPart.get();
         }
     }
     if (column != 0) {
         return nullptr;
     }
 
     PART_FETCH_CHILDREN(model);
     auto it = m_children.find(row);
     return it == m_children.end() ? nullptr : it->second.get();
 }
 
 void MessagePart::setSpecialParts(Ptr headerPart, Ptr textPart, Ptr mimePart, Ptr rawPart)
 {
     Q_ASSERT(!m_headerPart);
     Q_ASSERT(!m_textPart);
     Q_ASSERT(!m_mimePart);
     Q_ASSERT(!m_rawPart);
     m_headerPart = std::move(headerPart);
     m_textPart = std::move(textPart);
     m_mimePart = std::move(mimePart);
     m_rawPart = std::move(rawPart);
 }
 
 #ifdef MIME_TREE_DEBUG
 QDebug operator<<(QDebug dbg, const MessagePart &part)
 {
     return dbg << part.dump(0).data();
 }
 
 QByteArray MessagePart::dump(const int nestingLevel) const
 {
     const QByteArray spacing(nestingLevel, ' ');
     QByteArray res = spacing + QByteArray::number(row()) + ": " + dumpLocalInfo() +
             " (0x" + QByteArray::number(reinterpret_cast<const qulonglong>(this), 16) + ", " +
             data(Imap::Mailbox::RolePartMimeType).toByteArray() + ", " +
             data(Imap::Mailbox::RolePartPathToPart).toByteArray()
             + ") {\n";
     for (const auto &child: m_children) {
         if (child.second->parent() != this) {
             res += spacing + "  v-- next child has wrong parent "
                              "0x" + QByteArray::number(reinterpret_cast<const qulonglong>(child.second->parent()), 16) + " --v \n";
         }
         res += child.second->dump(nestingLevel + 2);
     }
     res += spacing + "}\n";
     return res;
 }
 
 QByteArray MessagePart::dumpLocalInfo() const
 {
     return "MessagePart";
 }
 #endif
 
 TopLevelMessage::TopLevelMessage(const QModelIndex &messageRoot, MessageModel *model)
     : MessagePart(nullptr, 0)
     , m_root(messageRoot)
     , m_model(model)
 {
     Q_ASSERT(m_root.isValid());
     m_model->m_map[m_root] = this;
 }
 
 TopLevelMessage::~TopLevelMessage()
 {
     for (auto it = m_model->m_map.begin(); it != m_model->m_map.end(); /* nothing */) {
         if (*it == this) {
             it = m_model->m_map.erase(it);
         } else {
             ++it;
         }
     }
 }
 
 QVariant TopLevelMessage::data(int role) const
 {
     return m_root.data(role);
 }
 
 void TopLevelMessage::fetchChildren(MessageModel *model)
 {
     // This is where the magic happens -- this class is just a dumb, fake node, so we're inserting something real below.
     // The stuff below still points to the message root, *not* to an actual message part, and everybody is happy that way.
 
     if (m_childrenState == FetchingState::NONE) {
         // trigger a fetch within the original model
         m_root.model()->rowCount(m_root);
 
         if (m_root.child(0, 0).isValid()) {
             // OK, we can do it synchronously.
             // Note that we are *not* guarding this based on a RoleIsFetched because that thing might not be true
             // when the rowsInserted() is called.
             m_children[0] = Ptr(new ProxyMessagePart(this, 0, m_root, model));
             m_childrenState = FetchingState::DONE;
         } else {
             // The upstream model is loading its stuff, okay, let's do it asynchronously.
             m_childrenState = FetchingState::LOADING;
             model->m_insertRows = model->connect(model->m_message.model(), &QAbstractItemModel::rowsInserted,
                                                  model, [this, model](const QModelIndex &idx) {
                 if (idx == model->m_message) {
                     model->disconnect(model->m_insertRows);
+                    if (!m_root.isValid()) {
+                        return;
+                    }
                     Q_ASSERT(m_root.isValid());
                     m_childrenState = MessagePart::FetchingState::NONE;
                     model->beginInsertRows(QModelIndex(), 0, 0);
                     fetchChildren(model);
                     model->endInsertRows();
                 }
             });
         }
     }
 }
 
 #ifdef MIME_TREE_DEBUG
 QByteArray TopLevelMessage::dumpLocalInfo() const
 {
     return "TopLevelMessage";
 }
 #endif
 
 
 ProxyMessagePart::ProxyMessagePart(MessagePart *parent, const int row, const QModelIndex &sourceIndex, MessageModel *model)
     : MessagePart(parent, row)
     , m_sourceIndex(sourceIndex)
     , m_model(model)
 {
     m_model->m_map[sourceIndex] = this;
 }
 
 ProxyMessagePart::~ProxyMessagePart()
 {
     for (auto it = m_model->m_map.begin(); it != m_model->m_map.end(); /* nothing */) {
         if (*it == this) {
             it = m_model->m_map.erase(it);
         } else {
             ++it;
         }
     }
 }
 
 QVariant ProxyMessagePart::data(int role) const
 {
     if (auto msg = dynamic_cast<TopLevelMessage *>(parent())) {
         switch (role) {
         case Qt::DisplayRole:
             return QStringLiteral("[fake message root: UID %1]").arg(
                         msg->data(Imap::Mailbox::RoleMessageUid).toString());
         }
     }
     return m_sourceIndex.data(role);
 }
 
 void ProxyMessagePart::fetchChildren(MessageModel *model)
 {
     QModelIndex index = parent() ? QModelIndex(m_sourceIndex) : model->message();
     if (!index.isValid()) {
         return;
     }
     switch (m_childrenState) {
     case FetchingState::DONE:
     case FetchingState::LOADING:
     case FetchingState::UNAVAILABLE:
         return;
     case FetchingState::NONE:
         break;
     }
 
     auto headerIdx = index.child(0, Imap::Mailbox::TreeItem::OFFSET_HEADER);
     auto textIdx = index.child(0, Imap::Mailbox::TreeItem::OFFSET_TEXT);
     auto mimeIdx = index.child(0, Imap::Mailbox::TreeItem::OFFSET_MIME);
     auto rawIdx = index.child(0, Imap::Mailbox::TreeItem::OFFSET_RAW_CONTENTS);
 
     setSpecialParts(
                 std::unique_ptr<ProxyMessagePart>(headerIdx.isValid() ? new ProxyMessagePart(this, 0, headerIdx, model) : nullptr),
                 std::unique_ptr<ProxyMessagePart>(textIdx.isValid() ? new ProxyMessagePart(this, 0, textIdx, model) : nullptr),
                 std::unique_ptr<ProxyMessagePart>(mimeIdx.isValid() ? new ProxyMessagePart(this, 0, mimeIdx, model) : nullptr),
                 std::unique_ptr<ProxyMessagePart>(rawIdx.isValid() ? new ProxyMessagePart(this, 0, rawIdx, model) : nullptr)
                 );
 
     m_childrenState = FetchingState::LOADING;
     int row = 0;
     while (true) {
         auto childIndex = index.child(row, 0);
         if (!childIndex.isValid()) {
             break;
         }
 
         auto part = Ptr(new ProxyMessagePart(this, row, childIndex, model));
 
         // Find out if something wants to override our choice
         for (const auto &module: model->m_partHandlers) {
             part = module->createPart(model, this, std::move(part), childIndex, model->createIndex(this->row(), 0, this));
         }
 
         m_children[row] = std::move(part);
         ++row;
     }
     m_childrenState = FetchingState::DONE;
 }
 
 #ifdef MIME_TREE_DEBUG
 QByteArray ProxyMessagePart::dumpLocalInfo() const
 {
     return "ProxyMessagePart";
 }
 #endif
 
 
 LocalMessagePart::LocalMessagePart(MessagePart *parent, const int row, const QByteArray &mimetype)
     : MessagePart(parent, row)
     , m_localState(FetchingState::NONE)
     , m_hdrListPostNo(false)
     , m_mimetype(mimetype)
     , m_octets(0)
 {
 }
 
 LocalMessagePart::~LocalMessagePart()
 {
 }
 
 void LocalMessagePart::fetchChildren(MessageModel *model)
 {
     return;
 }
 
 void LocalMessagePart::setChild(int row, Ptr part)
 {
     Q_ASSERT((int)m_children.size() >= row);
     Q_ASSERT(part);
     Q_ASSERT(row == part->row());
     m_children[row] = std::move(part);
 }
 
 void LocalMessagePart::setData(const QByteArray &data)
 {
     m_data = data;
     m_localState = FetchingState::DONE;
 }
 
 void LocalMessagePart::setCharset(const QByteArray &charset)
 {
     m_charset = charset;
 }
 
 void LocalMessagePart::setContentFormat(const QByteArray &format)
 {
     m_contentFormat = format;
 }
 
 void LocalMessagePart::setDelSp(const QByteArray &delSp)
 {
     m_delSp = delSp;
 }
 
 void LocalMessagePart::setFilename(const QString &filename)
 {
     m_filename = filename;
 }
 
 void LocalMessagePart::setTransferEncoding(const QByteArray &transferEncoding)
 {
     m_transferEncoding = transferEncoding;
 }
 
 void LocalMessagePart::setBodyFldId(const QByteArray &bodyFldId)
 {
     m_bodyFldId = bodyFldId;
 }
 
 void LocalMessagePart::setBodyDisposition(const QByteArray &bodyDisposition)
 {
     m_bodyDisposition = bodyDisposition;
 }
 
 void LocalMessagePart::setMultipartRelatedStartPart(const QByteArray &startPart)
 {
     m_multipartRelatedStartPart = startPart;
 }
 
 void LocalMessagePart::setOctets(uint octets)
 {
     m_octets = octets;
 }
 
 void LocalMessagePart::setEnvelope(std::unique_ptr<Imap::Message::Envelope> envelope)
 {
     m_envelope = std::move(envelope);
 }
 
 void LocalMessagePart::setHdrReferences(const QList<QByteArray> &references)
 {
     m_hdrReferences = references;
 }
 
 void LocalMessagePart::setHdrListPost(const QList<QUrl> &listPost)
 {
     m_hdrListPost = listPost;
 }
 
 void LocalMessagePart::setHdrListPostNo(const bool listPostNo)
 {
     m_hdrListPostNo = listPostNo;
 }
 
 void LocalMessagePart::setBodyFldParam(const QMap<QByteArray, QByteArray> &bodyFldParam)
 {
     m_bodyFldParam = bodyFldParam;
 }
 
 bool LocalMessagePart::isTopLevelMultipart() const
 {
     return m_mimetype.startsWith("multipart/") && (!parent()->parent() || parent()->data(Imap::Mailbox::RolePartMimeType).toByteArray().startsWith("message/"));
 }
 
 QByteArray LocalMessagePart::partId() const
 {
     if (isTopLevelMultipart())
         return QByteArray();
 
     QByteArray id = QByteArray::number(row() + 1);
     if (parent() && !parent()->data(Imap::Mailbox::RolePartId).toByteArray().isEmpty())
         id = parent()->data(Imap::Mailbox::RolePartId).toByteArray() + '.' + id;
 
     return id;
 }
 
 QByteArray LocalMessagePart::pathToPart() const {
     QByteArray parentPath;
     if (parent()) {
         parentPath = parent()->data(Imap::Mailbox::RolePartPathToPart).toByteArray();
     }
 
     return parentPath + '/' + QByteArray::number(row());
 }
 
 QVariant LocalMessagePart::data(int role) const
 {
     // The first three roles are for debugging purposes only
     switch (role) {
     case Qt::DisplayRole:
         if (isTopLevelMultipart()) {
             return QString::fromUtf8(m_mimetype);
         } else {
             return QString(QString::fromUtf8(partId()) + QStringLiteral(": ") + QString::fromUtf8(m_mimetype));
         }
     case Qt::ToolTipRole:
         if (m_mimetype == "message/rfc822") {
             Q_ASSERT(m_envelope);
             QString buf;
             QTextStream stream(&buf);
             stream << *m_envelope;
             return UiUtils::Formatting::htmlEscaped(buf);
         } else {
             return m_octets > 10000 ? QStringLiteral("%1 bytes of data").arg(m_octets) : QString::fromUtf8(m_data);
         }
     case Qt::FontRole:
     {
         QFont f;
         f.setItalic(true);
         return f;
     }
     case Imap::Mailbox::RoleIsFetched:
         return m_localState == FetchingState::DONE;
     case Imap::Mailbox::RoleMessageEnvelope:
         if (m_envelope) {
             return QVariant::fromValue<Imap::Message::Envelope>(*m_envelope);
         } else {
             return QVariant();
         }
     case Imap::Mailbox::RoleMessageHeaderReferences:
         return QVariant::fromValue(m_hdrReferences);
     case Imap::Mailbox::RoleMessageHeaderListPost:
     {
         QVariantList res;
         Q_FOREACH(const QUrl &url, m_hdrListPost)
             res << url;
         return res;
     }
     case Imap::Mailbox::RoleMessageHeaderListPostNo:
         return m_hdrListPostNo;
     case Imap::Mailbox::RoleIsUnavailable:
         return m_localState == FetchingState::UNAVAILABLE;
     case Imap::Mailbox::RolePartData:
         return m_data;
     case Imap::Mailbox::RolePartUnicodeText:
         if (m_mimetype.startsWith("text/")) {
             return Imap::decodeByteArray(m_data, m_charset);
         } else {
             return QVariant();
         }
     case Imap::Mailbox::RolePartMimeType:
         return m_mimetype;
     case Imap::Mailbox::RolePartCharset:
         return m_charset;
     case Imap::Mailbox::RolePartContentFormat:
         return m_contentFormat;
     case Imap::Mailbox::RolePartContentDelSp:
         return m_delSp;
     case Imap::Mailbox::RolePartTransferEncoding:
         return m_transferEncoding;
     case Imap::Mailbox::RolePartBodyFldId:
         return m_bodyFldId;
     case Imap::Mailbox::RolePartBodyDisposition:
         return m_bodyDisposition;
     case Imap::Mailbox::RolePartFileName:
         return m_filename;
     case Imap::Mailbox::RolePartOctets:
         return m_octets;
     case Imap::Mailbox::RolePartId:
         return partId();
     case Imap::Mailbox::RolePartPathToPart:
         return pathToPart();
     case Imap::Mailbox::RolePartMultipartRelatedMainCid:
         if (m_multipartRelatedStartPart.isEmpty()) {
             return m_multipartRelatedStartPart;
         } else {
             return QVariant();
         }
     case Imap::Mailbox::RolePartIsTopLevelMultipart:
         return isTopLevelMultipart();
     case Imap::Mailbox::RolePartForceFetchFromCache:
         return QVariant(); // Nothing to do here
     case Imap::Mailbox::RolePartBufferPtr:
         return QVariant::fromValue(const_cast<QByteArray*>(&m_data));
     case Imap::Mailbox::RoleMessageDate:
         return m_envelope ? m_envelope->date : QDateTime();
     case Imap::Mailbox::RoleMessageSubject:
         return m_envelope ? m_envelope->subject : QString();
     case Imap::Mailbox::RoleMessageFrom:
         return m_envelope ? Imap::Mailbox::TreeItemMessage::addresListToQVariant(m_envelope->from) : QVariant();
     case Imap::Mailbox::RoleMessageSender:
         return m_envelope ? Imap::Mailbox::TreeItemMessage::addresListToQVariant(m_envelope->sender) : QVariant();
     case Imap::Mailbox::RoleMessageReplyTo:
         return m_envelope ? Imap::Mailbox::TreeItemMessage::addresListToQVariant(m_envelope->replyTo) : QVariant();
     case Imap::Mailbox::RoleMessageTo:
         return m_envelope ? Imap::Mailbox::TreeItemMessage::addresListToQVariant(m_envelope->to) : QVariant();
     case Imap::Mailbox::RoleMessageCc:
         return m_envelope ? Imap::Mailbox::TreeItemMessage::addresListToQVariant(m_envelope->cc) : QVariant();
     case Imap::Mailbox::RoleMessageBcc:
         return m_envelope ? Imap::Mailbox::TreeItemMessage::addresListToQVariant(m_envelope->bcc) : QVariant();
     case Imap::Mailbox::RoleMessageMessageId:
         return m_envelope ? m_envelope->messageId : QByteArray();
     case Imap::Mailbox::RoleMessageInReplyTo:
         return m_envelope ? QVariant::fromValue(m_envelope->inReplyTo) : QVariant();
     case Imap::Mailbox::RoleMessageFlags:
         return QVariant();
     case Imap::Mailbox::RolePartBodyFldParam:
         return QVariant::fromValue<decltype(m_bodyFldParam)>(m_bodyFldParam);
     default:
         break;
     }
 
     return QVariant();
 }
 
 #ifdef MIME_TREE_DEBUG
 QByteArray LocalMessagePart::dumpLocalInfo() const
 {
     return "LocalMessagePart";
 }
 #endif
 
 
 }