diff --git a/agents/unifiedmailboxagent/unifiedmailboxeditor.cpp b/agents/unifiedmailboxagent/unifiedmailboxeditor.cpp
index 255c84709..52d452079 100644
--- a/agents/unifiedmailboxagent/unifiedmailboxeditor.cpp
+++ b/agents/unifiedmailboxagent/unifiedmailboxeditor.cpp
@@ -1,172 +1,172 @@
 /*
    Copyright (C) 2018 Daniel Vrátil <dvratil@kde.org>
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this program; see the file COPYING.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
 */
 
 #include "unifiedmailboxeditor.h"
 #include "mailkernel.h"
 
 #include <QVBoxLayout>
 #include <QFormLayout>
 #include <QLineEdit>
 #include <QPushButton>
 #include <QDialogButtonBox>
 #include <QSortFilterProxyModel>
 #include <QLabel>
 
 #include <KIconDialog>
 #include <KLocalizedString>
 #include <KCheckableProxyModel>
 
 #include <MailCommon/FolderTreeView>
 #include <MailCommon/FolderTreeWidget>
 
 namespace {
 
 class SelfFilterProxyModel : public QSortFilterProxyModel
 {
     Q_OBJECT
 public:
     explicit SelfFilterProxyModel(QObject *parent = nullptr)
         : QSortFilterProxyModel(parent)
     {}
 
     QVariant data(const QModelIndex &index, int role) const override
     {
         if (role == Qt::CheckStateRole) {
             // Make top-level collections uncheckable
             const Akonadi::Collection col = data(index, Akonadi::EntityTreeModel::CollectionRole).value<Akonadi::Collection>();
             if (col.parentCollection() == Akonadi::Collection::root()) {
                 return {};
             }
         }
 
         return QSortFilterProxyModel::data(index, role);
     }
 
     Qt::ItemFlags flags(const QModelIndex &index) const override
     {
         // Make top-level collections uncheckable
         const Akonadi::Collection col = data(index, Akonadi::EntityTreeModel::CollectionRole).value<Akonadi::Collection>();
         if (col.parentCollection() == Akonadi::Collection::root()) {
             return QSortFilterProxyModel::flags(index) & ~Qt::ItemIsUserCheckable;
         } else {
             return QSortFilterProxyModel::flags(index);
         }
     }
 
     bool filterAcceptsRow(int source_row, const QModelIndex &source_parent) const override
     {
         // Hide ourselves
         const auto sourceIndex = sourceModel()->index(source_row, 0, source_parent);
         const Akonadi::Collection col = sourceModel()->data(sourceIndex, Akonadi::EntityTreeModel::CollectionRole).value<Akonadi::Collection>();
-        return UnifiedMailboxManager::isUnifiedMailbox(col);
+        return !UnifiedMailboxManager::isUnifiedMailbox(col);
     }
 };
 
 }
 
 UnifiedMailboxEditor::UnifiedMailboxEditor(QWidget* parent)
     : UnifiedMailboxEditor({}, parent)
 {
 }
 
 UnifiedMailboxEditor::UnifiedMailboxEditor(UnifiedMailbox mailbox, QWidget *parent)
     : QDialog(parent)
     , mBox(std::move(mailbox))
 {
     resize(500, 900);
 
     auto l = new QVBoxLayout;
     setLayout(l);
 
     auto f = new QFormLayout;
     l->addLayout(f);
     auto nameEdit = new QLineEdit(mBox.name());
     f->addRow(i18n("Name:"), nameEdit);
     connect(nameEdit, &QLineEdit::textChanged,
             this, [this](const QString &name) {
                 mBox.setName(name);
             });
 
     auto iconButton = new QPushButton(QIcon::fromTheme(mBox.icon(), QIcon::fromTheme(QStringLiteral("folder-mail"))),
                                                            i18n("Pick icon..."));
     f->addRow(i18n("Icon:"), iconButton);
     connect(iconButton, &QPushButton::clicked,
             this, [iconButton, this]() {
                 const auto iconName = KIconDialog::getIcon();
                 if (!iconName.isEmpty()) {
                     mBox.setIcon(iconName);
                     iconButton->setIcon(QIcon::fromTheme(iconName));
                 }
             });
     mBox.setIcon(iconButton->icon().name());
 
     l->addSpacing(10);
 
     auto ftw = new MailCommon::FolderTreeWidget(nullptr, nullptr,
             MailCommon::FolderTreeWidget::TreeViewOptions(MailCommon::FolderTreeWidget::UseDistinctSelectionModel |
                                                           MailCommon::FolderTreeWidget::HideStatistics));
     l->addWidget(ftw);
 
     auto ftv = ftw->folderTreeView();
     auto sourceModel = ftv->model();
     auto selectionModel = ftw->selectionModel();
 
     auto checkable = new KCheckableProxyModel(this);
     checkable->setSourceModel(sourceModel);
     checkable->setSelectionModel(selectionModel);
     const auto sources = mBox.sourceCollections();
     for (const auto source : sources) {
         const auto index = Akonadi::EntityTreeModel::modelIndexForCollection(selectionModel->model(), Akonadi::Collection(source));
         selectionModel->select(index, QItemSelectionModel::Select);
     }
     connect(checkable->selectionModel(), &QItemSelectionModel::selectionChanged,
             this, [this](const QItemSelection &selected, const QItemSelection &deselected) {
                 auto indexes = selected.indexes();
                 for (const auto &index : indexes) {
                     mBox.addSourceCollection(index.data(Akonadi::EntityTreeModel::CollectionIdRole).toLongLong());
                 }
                 indexes = deselected.indexes();
                 for (const auto &index : indexes) {
                     mBox.removeSourceCollection(index.data(Akonadi::EntityTreeModel::CollectionIdRole).toLongLong());
                 }
             });
 
     auto selfFilter = new SelfFilterProxyModel(this);
     selfFilter->setSourceModel(checkable);
 
     ftv->setModel(selfFilter);
     ftv->expandAll();
 
     auto box = new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel, this);
     connect(box, &QDialogButtonBox::accepted, this, &QDialog::accept);
     connect(box, &QDialogButtonBox::rejected, this, &QDialog::reject);
     connect(nameEdit, &QLineEdit::textChanged,
             box, [box](const QString &name) {
                 box->button(QDialogButtonBox::Ok)->setEnabled(!name.isEmpty());
             });
     box->button(QDialogButtonBox::Ok)->setEnabled(!nameEdit->text().isEmpty());
     l->addWidget(box);
 }
 
 UnifiedMailbox UnifiedMailboxEditor::box() const
 {
     return mBox;
 }
 
 #include "unifiedmailboxeditor.moc"