diff --git a/libs/ui/KisChangeCloneLayersCommand.cpp b/libs/ui/KisChangeCloneLayersCommand.cpp
index e5eb7a1bb6..bbec880008 100644
--- a/libs/ui/KisChangeCloneLayersCommand.cpp
+++ b/libs/ui/KisChangeCloneLayersCommand.cpp
@@ -1,58 +1,58 @@
 /*
  *  Copyright (c) 2019 Tusooa Zhu <tusooa@vista.aero>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
 #include "KisChangeCloneLayersCommand.h"
 
 #include <kis_clone_layer.h>
 
 struct KisChangeCloneLayersCommand::Private
 {
     QList<KisCloneLayerSP> cloneLayers;
     QList<KisLayerSP> originalSource;
     KisLayerSP newSource;
 };
 
 KisChangeCloneLayersCommand::KisChangeCloneLayersCommand(QList<KisCloneLayerSP> cloneLayers, KisLayerSP newSource, KUndo2Command *parent)
     : KUndo2Command(kundo2_i18n("Change Clone Layers"), parent)
     , d(new Private())
 {
-    Q_ASSERT(!cloneLayers.isEmpty());
+    KIS_SAFE_ASSERT_RECOVER_RETURN(!cloneLayers.isEmpty());
     d->cloneLayers = cloneLayers;
     Q_FOREACH (KisCloneLayerSP layer, d->cloneLayers) {
         d->originalSource << layer->copyFrom();
     }
     d->newSource = newSource;
 }
 
 void KisChangeCloneLayersCommand::redo()
 {
     Q_FOREACH (KisCloneLayerSP layer, d->cloneLayers) {
         layer->setCopyFrom(d->newSource);
         layer->setDirty();
     }
 }
 
 void KisChangeCloneLayersCommand::undo()
 {
-    Q_ASSERT(d->cloneLayers.size() == d->originalSource.size());
+    KIS_SAFE_ASSERT_RECOVER_RETURN(d->cloneLayers.size() == d->originalSource.size());
     for (int i = 0; i < d->cloneLayers.size(); ++i) {
         KisCloneLayerSP layer = d->cloneLayers.at(i);
         layer->setCopyFrom(d->originalSource.at(i));
         layer->setDirty();
     }
 }
diff --git a/libs/ui/dialogs/KisDlgChangeCloneSource.cpp b/libs/ui/dialogs/KisDlgChangeCloneSource.cpp
index 568b6e1115..29f1fb1d25 100644
--- a/libs/ui/dialogs/KisDlgChangeCloneSource.cpp
+++ b/libs/ui/dialogs/KisDlgChangeCloneSource.cpp
@@ -1,139 +1,139 @@
 /*
  *  Copyright (c) 2019 Tusooa Zhu <tusooa@vista.aero>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
 #include "KisDlgChangeCloneSource.h"
 
 #include <kis_clone_layer.h>
 #include <kis_image.h>
 #include <kis_undo_adapter.h>
 
 #include "KisViewManager.h"
 #include "KisChangeCloneLayersCommand.h"
 
 struct KisDlgChangeCloneSource::Private
 {
     QList<KisCloneLayerSP> cloneLayers;
     KisViewManager *view;
     QList<KisLayerSP> validTargets;
     Ui::WdgChangeCloneSource ui;
     KisNodeSP rootNode;
 
     void addToTargetListRecursively(KisNodeSP node, bool addSelf = true);
     void filterOutAncestorsAndClonesRecursively(KisLayerSP layer);
 };
 
 void KisDlgChangeCloneSource::Private::addToTargetListRecursively(KisNodeSP node, bool addSelf)
 {
     if (!node) {
         return;
     }
     if (addSelf) {
         KisLayerSP layer(qobject_cast<KisLayer *>(node.data()));
         if (layer) {
             validTargets << layer;
         }
     }
     for (KisNodeSP childNode = node->lastChild(); childNode; childNode = childNode->prevSibling()) {
         KisLayerSP childLayer(qobject_cast<KisLayer *>(childNode.data()));
         if (childLayer) {
             addToTargetListRecursively(childLayer);
         }
     }
 
 }
 
 void KisDlgChangeCloneSource::Private::filterOutAncestorsAndClonesRecursively(KisLayerSP layer)
 {
     validTargets.removeOne(layer);
     // remove `layer` and its ancestors
     KisLayerSP parent = qobject_cast<KisLayer *>(layer->parent().data());
     if (parent) {
         filterOutAncestorsAndClonesRecursively(parent);
     }
 
     // remove all clones of `layer`, and their ancestors
     Q_FOREACH (KisCloneLayerSP clone, layer->registeredClones()) {
         filterOutAncestorsAndClonesRecursively(clone);
     }
 }
 
 
 KisDlgChangeCloneSource::KisDlgChangeCloneSource(QList<KisCloneLayerSP> layers, KisViewManager *view, QWidget *parent)
     : KoDialog(parent)
     , d(new Private())
 {
-    Q_ASSERT(!layers.isEmpty());
+    KIS_SAFE_ASSERT_RECOVER_RETURN(!layers.isEmpty());
     d->cloneLayers = layers;
     d->view = view;
 
     setButtons(Ok | Cancel);
     setDefaultButton(Ok);
 
     QWidget *widget = new QWidget(this);
     d->ui.setupUi(widget);
     setMainWidget(widget);
 
     updateTargetLayerList();
 }
 
 KisDlgChangeCloneSource::~KisDlgChangeCloneSource()
 {
     if (result() == QDialog::Accepted) {
         int index = d->ui.cmbSourceLayer->currentIndex();
         if (index != -1) {
             KisLayerSP targetLayer = d->validTargets.at(index);
             KisChangeCloneLayersCommand *command = new KisChangeCloneLayersCommand(d->cloneLayers, targetLayer);
             d->view->undoAdapter()->addCommand(command);
         }
     }
 }
 
 void KisDlgChangeCloneSource::updateTargetLayerList()
 {
     KisImageWSP image = d->view->image();
     if (!image) {
         return;
     }
     KisNodeSP root = image->root();
     d->rootNode = root;
     d->validTargets.clear();
     d->addToTargetListRecursively(root, /* addSelf = */ false);
 
     KisLayerSP commonCopyFrom(d->cloneLayers.first()->copyFrom());
 
     Q_FOREACH (KisCloneLayerSP clone, d->cloneLayers) {
         // filter out invalid targets:
         // selected clone layers, their ancestors;
         // the clone layers' registered clone, the clones' ancestors.
         d->filterOutAncestorsAndClonesRecursively(clone);
 
         // assume that clone->copyFrom() != 0
         if (clone->copyFrom() != commonCopyFrom) {
             commonCopyFrom = 0;
         }
     }
 
     d->ui.cmbSourceLayer->clear();
     Q_FOREACH (KisNodeSP node, d->validTargets) {
         d->ui.cmbSourceLayer->addItem(node->name());
     }
 
     if (commonCopyFrom) {
         d->ui.cmbSourceLayer->setCurrentIndex(d->validTargets.indexOf(commonCopyFrom));
     }
 }