diff --git a/src/cantor_part.cpp b/src/cantor_part.cpp
index b07de62b..4620e15d 100644
--- a/src/cantor_part.cpp
+++ b/src/cantor_part.cpp
@@ -1,973 +1,975 @@
 /*
     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.
 
     ---
     Copyright (C) 2009 Alexander Rieder <alexanderrieder@gmail.com>
 */
 
 #include "cantor_part.h"
 
 #include <config-cantor.h>
 
 #include <KLocalizedString>
 #include <QIcon>
 #include <KParts/Event>
 #include <KParts/GUIActivateEvent>
 #include <KPluginFactory>
 #include <KAboutData>
 
 #include <QAction>
 #include <KActionCollection>
 #include <QFileDialog>
 #include <KStandardAction>
 #include <KZip>
 #include <KToggleAction>
 #include <KService>
 #include <KServiceTypeTrader>
 #include <KRun>
 #include <QProgressDialog>
 #include <KMessageBox>
 #include <KNS3/UploadDialog>
 #include <KXMLGUIFactory>
 
 #include <QElapsedTimer>
 #include <QFile>
 #include <QTextStream>
 #include <QTextEdit>
 #include <QTimer>
 #include <QPrinter>
 #include <QPrintPreviewDialog>
 #include <QPrintDialog>
 #include <QVBoxLayout>
 
 #include "worksheet.h"
 #include "worksheetview.h"
 #include "searchbar.h"
 #include "scripteditor/scripteditorwidget.h"
 #include "lib/backend.h"
 #include "lib/extension.h"
 #include "lib/assistant.h"
 #include "lib/panelpluginhandler.h"
 #include "lib/panelplugin.h"
 #include "lib/worksheetaccess.h"
 
 #include "settings.h"
 
 
 //A concrete implementation of the WorksheetAccesssInterface
 class WorksheetAccessInterfaceImpl : public Cantor::WorksheetAccessInterface
 {
 
   public:
     WorksheetAccessInterfaceImpl(QObject* parent, Worksheet* worksheet) :   WorksheetAccessInterface(parent),  m_worksheet(worksheet)
     {
         qDebug()<<"new worksheetaccess interface";
         connect(worksheet, SIGNAL(modified()), this, SIGNAL(modified()));
     }
 
     ~WorksheetAccessInterfaceImpl() override = default;
 
     QByteArray saveWorksheetToByteArray() override
     {
         return m_worksheet->saveToByteArray();
     }
 
     void loadWorksheetFromByteArray(QByteArray* data) override
     {
         m_worksheet->load(data);
     }
 
     Cantor::Session* session() override
     {
         return m_worksheet->session();
     }
 
   void evaluate() override
     {
         m_worksheet->evaluate();
     }
 
     void interrupt() override
     {
         m_worksheet->interrupt();
     }
 
   private:
     Worksheet* m_worksheet;
 };
 
 CantorPart::CantorPart( QWidget *parentWidget, QObject *parent, const QVariantList & args ): KParts::ReadWritePart(parent),
     m_searchBar(nullptr),
     m_initProgressDlg(nullptr),
     m_showProgressDlg(true),
     m_showBackendHelp(nullptr),
     m_statusBarBlocked(false),
     m_sessionStatusCounter(0)
 {
     m_panelHandler=new Cantor::PanelPluginHandler(this);
     connect(m_panelHandler, SIGNAL(pluginsChanged()), this, SLOT(pluginsChanged()));
 
     QString backendName;
     if(args.isEmpty())
         backendName=QLatin1String("null");
     else
         backendName=args.first().toString();
 
     for (const QVariant& arg : args)
     {
         if (arg.toString() == QLatin1String("--noprogress") )
         {
             qWarning()<<"not showing the progress bar by request";
             m_showProgressDlg=false;
         }
     }
 
     Cantor::Backend* b=Cantor::Backend::getBackend(backendName);
     if(!b)
     {
         KMessageBox::error(parentWidget, i18n("Backend %1 is not installed", backendName), i18n("Error - Cantor"));
         setWidget(new QWidget(parentWidget));
         return;
     }
 
     if (b && !b->isEnabled() && backendName != QLatin1String("null"))
     {
         KMessageBox::information(parentWidget, i18n("There are some problems with the %1 backend,\n"\
                                      "please check your configuration or install the needed packages.\n"
                                      "You will only be able to view this worksheet.", backendName), i18n("Cantor"));
         setWidget(new QWidget(parentWidget));
         return;
     }
 
     qDebug()<<"Backend "<<b->name()<<" offers extensions: "<<b->extensions();
 
 
     auto* collection = actionCollection();
 
     //central widget
     QWidget* widget = new QWidget(parentWidget);
     QVBoxLayout* layout = new QVBoxLayout(widget);
     m_worksheet=new Worksheet(b, widget);
     m_worksheetview=new WorksheetView(m_worksheet, widget);
     m_worksheetview->setEnabled(false); //disable input until the session has successfully logged in and emits the ready signal
     connect(m_worksheet, SIGNAL(modified()), this, SLOT(setModified()));
     connect(m_worksheet, SIGNAL(showHelp(QString)), this, SIGNAL(showHelp(QString)));
     connect(m_worksheet, SIGNAL(loaded()), this, SLOT(initialized()));
     connect(collection, SIGNAL(inserted(QAction*)), m_worksheet, SLOT(registerShortcut(QAction*)));
     layout->addWidget(m_worksheetview);
     setWidget(widget);
 
     //create WorksheetAccessInterface, used at the moment by LabPlot only to access Worksheet's API
     Cantor::WorksheetAccessInterface* iface = new WorksheetAccessInterfaceImpl(this, m_worksheet);
     Q_UNUSED(iface);
 
     //initialize actions
     m_worksheet->createActions(collection);
 
     KStandardAction::saveAs(this, SLOT(fileSaveAs()), collection);
     m_save = KStandardAction::save(this, SLOT(save()), collection);
     m_save->setPriority(QAction::LowPriority);
 
     QAction* savePlain = new QAction(i18n("Save Plain Text"), collection);
     collection->addAction(QLatin1String("file_save_plain"), savePlain);
     savePlain->setIcon(QIcon::fromTheme(QLatin1String("document-save")));
     connect(savePlain, SIGNAL(triggered()), this, SLOT(fileSavePlain()));
 
     QAction* undo = KStandardAction::undo(m_worksheet, SIGNAL(undo()), collection);
     undo->setPriority(QAction::LowPriority);
     connect(m_worksheet, SIGNAL(undoAvailable(bool)), undo, SLOT(setEnabled(bool)));
     m_editActions.push_back(undo);
 
     QAction* redo = KStandardAction::redo(m_worksheet, SIGNAL(redo()), collection);
     redo->setPriority(QAction::LowPriority);
     connect(m_worksheet, SIGNAL(redoAvailable(bool)), redo, SLOT(setEnabled(bool)));
     m_editActions.push_back(redo);
 
     QAction* cut = KStandardAction::cut(m_worksheet, SIGNAL(cut()), collection);
     cut->setPriority(QAction::LowPriority);
     connect(m_worksheet, SIGNAL(cutAvailable(bool)), cut, SLOT(setEnabled(bool)));
     m_editActions.push_back(cut);
 
     QAction* copy = KStandardAction::copy(m_worksheet, SIGNAL(copy()), collection);
     copy->setPriority(QAction::LowPriority);
     connect(m_worksheet, SIGNAL(copyAvailable(bool)), copy, SLOT(setEnabled(bool)));
 
     QAction* paste = KStandardAction::paste(m_worksheet, SLOT(paste()), collection);
     paste->setPriority(QAction::LowPriority);
     connect(m_worksheet, SIGNAL(pasteAvailable(bool)), paste, SLOT(setEnabled(bool)));
     m_editActions.push_back(paste);
 
     QAction* find = KStandardAction::find(this, SLOT(showSearchBar()), collection);
     find->setPriority(QAction::LowPriority);
 
     QAction* replace = KStandardAction::replace(this, SLOT(showExtendedSearchBar()), collection);
     replace->setPriority(QAction::LowPriority);
     m_editActions.push_back(replace);
 
     m_findNext = KStandardAction::findNext(this, SLOT(findNext()), collection);
     m_findNext->setEnabled(false);
 
     m_findPrev = KStandardAction::findPrev(this, SLOT(findPrev()), collection);
     m_findPrev->setEnabled(false);
 
     QAction* latexExport = new QAction(i18n("Export to LaTeX"), collection);
     collection->addAction(QLatin1String("file_export_latex"), latexExport);
     latexExport->setIcon(QIcon::fromTheme(QLatin1String("document-export")));
     connect(latexExport, SIGNAL(triggered()), this, SLOT(exportToLatex()));
 
     QAction* print = KStandardAction::print(this, SLOT(print()), collection);
     print->setPriority(QAction::LowPriority);
 
     QAction* printPreview = KStandardAction::printPreview(this, SLOT(printPreview()), collection);
     printPreview->setPriority(QAction::LowPriority);
 
     KStandardAction::zoomIn(m_worksheetview, SLOT(zoomIn()), collection);
     KStandardAction::zoomOut(m_worksheetview, SLOT(zoomOut()), collection);
     KStandardAction::actualSize(m_worksheetview, SLOT(actualSize()), collection);
 
     m_evaluate = new QAction(i18n("Evaluate Worksheet"), collection);
     collection->addAction(QLatin1String("evaluate_worksheet"), m_evaluate);
     m_evaluate->setIcon(QIcon::fromTheme(QLatin1String("system-run")));
     collection->setDefaultShortcut(m_evaluate, Qt::CTRL+Qt::Key_E);
     connect(m_evaluate, SIGNAL(triggered()), this, SLOT(evaluateOrInterrupt()));
     m_editActions.push_back(m_evaluate);
 
     m_typeset = new KToggleAction(i18n("Typeset using LaTeX"), collection);
     m_typeset->setChecked(Settings::self()->typesetDefault());
     // Disable until login, because we use session command for this action
     m_typeset->setEnabled(false);
     collection->addAction(QLatin1String("enable_typesetting"), m_typeset);
     connect(m_typeset, SIGNAL(toggled(bool)), this, SLOT(enableTypesetting(bool)));
 
     m_highlight = new KToggleAction(i18n("Syntax Highlighting"), collection);
     m_highlight->setChecked(Settings::self()->highlightDefault());
     collection->addAction(QLatin1String("enable_highlighting"), m_highlight);
     connect(m_highlight, SIGNAL(toggled(bool)), m_worksheet, SLOT(enableHighlighting(bool)));
 
     m_completion = new KToggleAction(i18n("Completion"), collection);
     m_completion->setChecked(Settings::self()->completionDefault());
     collection->addAction(QLatin1String("enable_completion"), m_completion);
     connect(m_completion, SIGNAL(toggled(bool)), m_worksheet, SLOT(enableCompletion(bool)));
 
     m_exprNumbering = new KToggleAction(i18n("Line Numbers"), collection);
     m_exprNumbering->setChecked(Settings::self()->expressionNumberingDefault());
     collection->addAction(QLatin1String("enable_expression_numbers"), m_exprNumbering);
     connect(m_exprNumbering, SIGNAL(toggled(bool)), m_worksheet, SLOT(enableExpressionNumbering(bool)));
 
     m_animateWorksheet = new KToggleAction(i18n("Animate Worksheet"), collection);
     m_animateWorksheet->setChecked(Settings::self()->animationDefault());
     collection->addAction(QLatin1String("enable_animations"), m_animateWorksheet);
     connect(m_animateWorksheet, SIGNAL(toggled(bool)), m_worksheet, SLOT(enableAnimations(bool)));
 
-    QAction* restart = new QAction(i18n("Restart Backend"), collection);
-    collection->addAction(QLatin1String("restart_backend"), restart);
-    restart->setIcon(QIcon::fromTheme(QLatin1String("system-reboot")));
-    connect(restart, SIGNAL(triggered()), this, SLOT(restartBackend()));
-    m_editActions.push_back(restart);
+    m_restart = new QAction(i18n("Restart Backend"), collection);
+    collection->addAction(QLatin1String("restart_backend"), m_restart);
+    m_restart->setIcon(QIcon::fromTheme(QLatin1String("system-reboot")));
+    connect(m_restart, SIGNAL(triggered()), this, SLOT(restartBackend()));
+    m_restart->setEnabled(false); // No need show restart button before login
+    m_editActions.push_back(m_restart);
 
     QAction* evaluateCurrent = new QAction(QIcon::fromTheme(QLatin1String("media-playback-start")), i18n("Evaluate Entry"), collection);
     collection->addAction(QLatin1String("evaluate_current"),  evaluateCurrent);
     collection->setDefaultShortcut(evaluateCurrent, Qt::SHIFT + Qt::Key_Return);
     connect(evaluateCurrent, SIGNAL(triggered()), m_worksheet, SLOT(evaluateCurrentEntry()));
     m_editActions.push_back(evaluateCurrent);
 
     QAction* insertCommandEntry = new QAction(QIcon::fromTheme(QLatin1String("run-build")), i18n("Insert Command Entry"), collection);
     collection->addAction(QLatin1String("insert_command_entry"),  insertCommandEntry);
     collection->setDefaultShortcut(insertCommandEntry, Qt::CTRL + Qt::Key_Return);
     connect(insertCommandEntry, SIGNAL(triggered()), m_worksheet, SLOT(insertCommandEntry()));
     m_editActions.push_back(insertCommandEntry);
 
     QAction* insertTextEntry = new QAction(QIcon::fromTheme(QLatin1String("draw-text")), i18n("Insert Text Entry"), collection);
     collection->addAction(QLatin1String("insert_text_entry"),  insertTextEntry);
     connect(insertTextEntry, SIGNAL(triggered()), m_worksheet, SLOT(insertTextEntry()));
     m_editActions.push_back(insertTextEntry);
 
 #ifdef Discount_FOUND
     QAction* insertMarkdownEntry = new QAction(QIcon::fromTheme(QLatin1String("text-x-markdown")), i18n("Insert Markdown Entry"), collection);
     collection->addAction(QLatin1String("insert_markdown_entry"),  insertMarkdownEntry);
     connect(insertMarkdownEntry, SIGNAL(triggered()), m_worksheet, SLOT(insertMarkdownEntry()));
     m_editActions.push_back(insertMarkdownEntry);
 #endif
 
 #ifdef WITH_EPS
     QAction* insertLatexEntry = new QAction(QIcon::fromTheme(QLatin1String("text-x-tex")), i18n("Insert Latex Entry"), collection);
     collection->addAction(QLatin1String("insert_latex_entry"),  insertLatexEntry);
     connect(insertLatexEntry, SIGNAL(triggered()), m_worksheet, SLOT(insertLatexEntry()));
     m_editActions.push_back(insertLatexEntry);
 #endif
 
     QAction* insertPageBreakEntry = new QAction(QIcon::fromTheme(QLatin1String("go-next-view-page")), i18n("Insert Page Break"), collection);
     collection->addAction(QLatin1String("insert_page_break_entry"), insertPageBreakEntry);
     connect(insertPageBreakEntry, SIGNAL(triggered()), m_worksheet, SLOT(insertPageBreakEntry()));
     m_editActions.push_back(insertPageBreakEntry);
 
     QAction* insertImageEntry = new QAction(QIcon::fromTheme(QLatin1String("image-x-generic")), i18n("Insert Image"), collection);
     collection->addAction(QLatin1String("insert_image_entry"), insertImageEntry);
     connect(insertImageEntry, SIGNAL(triggered()), m_worksheet, SLOT(insertImageEntry()));
     m_editActions.push_back(insertImageEntry);
 
     QAction* removeCurrent = new QAction(QIcon::fromTheme(QLatin1String("edit-delete")), i18n("Remove current Entry"), collection);
     collection->addAction(QLatin1String("remove_current"), removeCurrent);
     collection->setDefaultShortcut(removeCurrent, Qt::ShiftModifier + Qt::Key_Delete);
     connect(removeCurrent, SIGNAL(triggered()), m_worksheet, SLOT(removeCurrentEntry()));
     m_editActions.push_back(removeCurrent);
 
     m_showBackendHelp = new QAction(i18n("Show %1 Help", b->name()) , collection);
     m_showBackendHelp->setIcon(QIcon::fromTheme(QLatin1String("help-contents")));
     collection->addAction(QLatin1String("backend_help"), m_showBackendHelp);
     connect(m_showBackendHelp, SIGNAL(triggered()), this, SLOT(showBackendHelp()));
 
     // Disabled, because uploading to kde store from program don't work
     // See https://phabricator.kde.org/T9980 for details
     // If this situation will changed, then uncomment this action
     /*
     QAction* publishWorksheet = new QAction(i18n("Publish Worksheet"), collection);
     publishWorksheet->setIcon(QIcon::fromTheme(QLatin1String("get-hot-new-stuff")));
     collection->addAction(QLatin1String("file_publish_worksheet"), publishWorksheet);
     connect(publishWorksheet, SIGNAL(triggered()), this, SLOT(publishWorksheet()));
     */
 
     KToggleAction* showEditor = new KToggleAction(i18n("Show Script Editor"), collection);
     showEditor->setChecked(false);
     collection->addAction(QLatin1String("show_editor"), showEditor);
     connect(showEditor, SIGNAL(toggled(bool)), this, SLOT(showScriptEditor(bool)));
     showEditor->setEnabled(b->extensions().contains(QLatin1String("ScriptExtension")));
 
     QAction* showCompletion = new QAction(i18n("Show Completion"), collection);
     collection->addAction(QLatin1String("show_completion"), showCompletion);
     QList<QKeySequence> showCompletionShortcuts;
     showCompletionShortcuts << Qt::Key_Tab << Qt::CTRL + Qt::Key_Space;
     collection->setDefaultShortcuts(showCompletion, showCompletionShortcuts);
     connect(showCompletion, SIGNAL(triggered()), m_worksheet, SLOT(showCompletion()));
     m_editActions.push_back(showCompletion);
 
     // set our XML-UI resource file
     setXMLFile(QLatin1String("cantor_part.rc"));
 
     // we are read-write by default
     setReadWrite(true);
 
     // we are not modified since we haven't done anything yet
     setModified(false);
 
     initialized();
 }
 
 CantorPart::~CantorPart()
 {
     if (m_scriptEditor)
     {
         disconnect(m_scriptEditor, SIGNAL(destroyed()), this, SLOT(scriptEditorClosed()));
         delete m_scriptEditor;
     }
     if (m_searchBar)
         delete m_searchBar;
 }
 
 void CantorPart::setReadWrite(bool rw)
 {
     // notify your internal widget of the read-write state
     m_worksheetview->setInteractive(rw);
 
     ReadWritePart::setReadWrite(rw);
 }
 
 void CantorPart::setReadOnly()
 {
     for (QAction* action : m_editActions)
         action->setEnabled(false);
 
     if (m_showBackendHelp)
     {
         m_showBackendHelp->setEnabled(false);
         m_showBackendHelp->setVisible(false);
     }
 }
 
 void CantorPart::setModified(bool modified)
 {
     // get a handle on our Save action and make sure it is valid
     if (!m_save)
         return;
 
     // if so, we either enable or disable it based on the current state
     m_save->setEnabled(modified);
 
     // in any event, we want our parent to do it's thing
     ReadWritePart::setModified(modified);
 }
 
 KAboutData& CantorPart::createAboutData()
 {
     // the non-i18n name here must be the same as the directory in
     // which the part's rc file is installed ('partrcdir' in the Makefile)
     static KAboutData about(QLatin1String("cantorpart"),
                      QLatin1String("Cantor"),
                      QLatin1String(CANTOR_VERSION),
                      i18n("CantorPart"),
                      KAboutLicense::GPL,
                      i18n("(C) 2009-2015 Alexander Rieder"),
                      QString(),
                      QLatin1String("http://edu.kde.org/cantor"));
 
     about.addAuthor( i18n("Alexander Rieder"), QString(), QLatin1String("alexanderrieder@gmail.com") );
     return about;
 }
 
 bool CantorPart::openFile()
 {
     //don't crash if for some reason the worksheet is invalid
     if(m_worksheet==nullptr)
     {
         qWarning()<<"trying to open in an invalid cantor part";
         return false;
     }
 
     QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
     QElapsedTimer timer;
 	timer.start();
     const bool rc = m_worksheet->load(localFilePath());
     QApplication::restoreOverrideCursor();
 
     if (rc) {
         qDebug()<< "Worksheet successfully loaded in " <<  (float)timer.elapsed()/1000 << " seconds).";
         updateCaption();
         // We modified, but it we load file now, so no need in save option
         setModified(false);
     }
 
     return rc;
 }
 
 bool CantorPart::saveFile()
 {
     // if we aren't read-write, return immediately
     if (isReadWrite() == false)
         return false;
 
     qDebug()<<"saving to: "<<url();
     if (url().isEmpty())
         fileSaveAs();
     else
         m_worksheet->save( localFilePath() );
     setModified(false);
 
     return true;
 }
 
 void CantorPart::fileSaveAs()
 {
     // this slot is called whenever the File->Save As menu is selected
     QString worksheetFilter = i18n("Cantor Worksheet (*.cws)");
     QString filter = worksheetFilter;
 
     if (!m_worksheet->isReadOnly())
     {
         //if the backend supports scripts, also append their scriptFile endings to the filter
         Cantor::Backend * const backend=m_worksheet->session()->backend();
         if (backend->extensions().contains(QLatin1String("ScriptExtension")))
         {
             Cantor::ScriptExtension* e=dynamic_cast<Cantor::ScriptExtension*>(backend->extension(QLatin1String("ScriptExtension")));
             filter+=QLatin1String(";;")+e->scriptFileFilter();
         }
     }
 
     QString selectedFilter;
     QString file_name = QFileDialog::getSaveFileName(widget(), i18n("Save as"), QString(), filter, &selectedFilter);
     if (file_name.isEmpty())
         return;
 
     //depending on user's selection, save as a worksheet or as a plain script file
     if (selectedFilter == worksheetFilter)
     {
         if (!file_name.endsWith(QLatin1String(".cws")))
             file_name += QLatin1String(".cws");
         saveAs(QUrl::fromLocalFile(file_name));
     }
     else
         m_worksheet->savePlain(file_name);
 
     updateCaption();
 }
 
 void CantorPart::fileSavePlain()
 {
     QString file_name = QFileDialog::getSaveFileName(widget(), i18n("Save"), QString(), QString());
     if (!file_name.isEmpty())
         m_worksheet->savePlain(file_name);
 }
 
 void CantorPart::exportToLatex()
 {
     QString file_name = QFileDialog::getSaveFileName(widget(), i18n("Export to LaTeX"), QString(), QString());
 
     if (file_name.isEmpty() == false)
         {
         if (!file_name.endsWith(QLatin1String(".tex")))
             file_name += QLatin1String(".tex");
         m_worksheet->saveLatex(file_name);
         }
 }
 
 void CantorPart::guiActivateEvent( KParts::GUIActivateEvent * event )
 {
     KParts::ReadWritePart::guiActivateEvent(event);
     if(event->activated())
     {
         if(m_scriptEditor)
             m_scriptEditor->show();
     }else
     {
         if(m_scriptEditor)
             m_scriptEditor->hide();
     }
 }
 
 void CantorPart::evaluateOrInterrupt()
 {
     qDebug()<<"evalorinterrupt";
     if(m_worksheet->isRunning())
         m_worksheet->interrupt();
     else
         m_worksheet->evaluate();
 }
 void CantorPart::restartBackend()
 {
     bool restart = false;
     if (Settings::self()->warnAboutSessionRestart())
     {
         KMessageBox::ButtonCode tmp;
 
         // If we want the question box, but it is disable, then enable it
         if (!KMessageBox::shouldBeShownYesNo(QLatin1String("WarnAboutSessionRestart"), tmp))
             KMessageBox::enableMessage(QLatin1String("WarnAboutSessionRestart"));
 
         const QString& name = m_worksheet->session()->backend()->name();
         KMessageBox::ButtonCode rc = KMessageBox::questionYesNo(widget(),
             i18n("All the available calculation results will be lost. Do you really want to restart %1?", name),
             i18n("Restart %1?", name),
             KStandardGuiItem::yes(),
             KStandardGuiItem::no(),
             QLatin1String("WarnAboutSessionRestart")
         );
 
         // Update setting's value
         Settings::self()->setWarnAboutSessionRestart(
             KMessageBox::shouldBeShownYesNo(QLatin1String("WarnAboutSessionRestart"), tmp));
 
         restart = rc == KMessageBox::ButtonCode::Yes;
     }
     else
     {
         KMessageBox::ButtonCode rc;
         KMessageBox::shouldBeShownYesNo(QLatin1String("WarnAboutSessionRestart"), rc);
         restart = rc == KMessageBox::ButtonCode::Yes;
     }
 
     if (restart)
     {
         m_worksheet->session()->logout();
         m_worksheet->loginToSession();
     }
 }
 
 void CantorPart::worksheetStatusChanged(Cantor::Session::Status status)
 {
     qDebug()<<"wsStatusChange"<<status;
     unsigned int count = ++m_sessionStatusCounter;
     if(status==Cantor::Session::Running)
     {
         // Useless add a interrupt action without delay, because user physically can't interrupt fast commands
         QTimer::singleShot(100, this, [this, count] () {
             if(m_worksheet->session()->status() == Cantor::Session::Running && m_sessionStatusCounter == count)
             {
                 m_evaluate->setText(i18n("Interrupt"));
                 m_evaluate->setShortcut(Qt::CTRL+Qt::Key_I);
                 m_evaluate->setIcon(QIcon::fromTheme(QLatin1String("dialog-close")));
                 setStatusMessage(i18n("Calculating..."));
             }
         });
     }else if (status==Cantor::Session::Done)
     {
         m_evaluate->setText(i18n("Evaluate Worksheet"));
         m_evaluate->setShortcut(Qt::CTRL+Qt::Key_E);
         m_evaluate->setIcon(QIcon::fromTheme(QLatin1String("system-run")));
 
         setStatusMessage(i18n("Ready"));
     }
 }
 
 void CantorPart::showSessionError(const QString& message)
 {
     qDebug()<<"Error: "<<message;
     initialized();
     showImportantStatusMessage(i18n("Session Error: %1", message));
 }
 
 void CantorPart::initialized()
 {
     if (!m_worksheet->isReadOnly())
     {
         connect(m_worksheet->session(), SIGNAL(statusChanged(Cantor::Session::Status)), this, SLOT(worksheetStatusChanged(Cantor::Session::Status)));
         connect(m_worksheet->session(), SIGNAL(loginStarted()),this, SLOT(worksheetSessionLoginStarted()));
         connect(m_worksheet->session(), SIGNAL(loginDone()),this, SLOT(worksheetSessionLoginDone()));
         connect(m_worksheet->session(), SIGNAL(error(QString)), this, SLOT(showSessionError(QString)));
 
         loadAssistants();
         m_panelHandler->setSession(m_worksheet->session());
         adjustGuiToSession();
 
         // Don't set modification flag, if we add command entry in empty worksheet
         const bool modified = this->isModified();
         if (m_worksheet->isEmpty())
             m_worksheet->appendCommandEntry();
         setModified(modified);
     }
     else
     {
         setReadOnly();
         // Clear assistants
         for (KXMLGUIClient* client: childClients())
         {
             Cantor::Assistant* assistant = dynamic_cast<Cantor::Assistant*>(client);
             if (assistant)
             {
                 factory()->removeClient(client);
                 removeChildClient(client);
                 assistant->deleteLater();
             }
         }
     }
 
     m_worksheetview->setEnabled(true);
     m_worksheetview->setFocus();
 
     setStatusMessage(i18n("Initialization complete"));
     updateCaption();
 }
 
 void CantorPart::worksheetSessionLoginStarted() {
     setStatusMessage(i18n("Initializing..."));
     QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
 }
 
 void CantorPart::worksheetSessionLoginDone() {
     setStatusMessage(i18n("Ready"));
 
     m_typeset->setEnabled(true);
+    m_restart->setEnabled(true);
 
     QApplication::restoreOverrideCursor();
 }
 
 void CantorPart::enableTypesetting(bool enable)
 {
     m_worksheet->session()->setTypesettingEnabled(enable);
 }
 
 void CantorPart::showBackendHelp()
 {
     qDebug()<<"showing backends help";
     Cantor::Backend* backend=m_worksheet->session()->backend();
     QUrl url = backend->helpUrl();
     qDebug()<<"launching url "<<url;
     new KRun(url, widget());
 }
 
 Worksheet* CantorPart::worksheet()
 {
     return m_worksheet;
 }
 
 void CantorPart::updateCaption()
 {
     QString filename=url().fileName();
     //strip away the extension
     filename=filename.left(filename.lastIndexOf(QLatin1Char('.')));
 
     if (filename.isEmpty())
         filename=i18n("Unnamed");
 
     if (!m_worksheet->isReadOnly())
         emit setCaption(filename, QIcon::fromTheme(m_worksheet->session()->backend()->icon()));
     else
         emit setCaption(filename+QLatin1Char(' ')+i18n("[read-only]"), QIcon());
 }
 
 void CantorPart::pluginsChanged()
 {
     for (auto* plugin : m_panelHandler->plugins())
         connect(plugin, SIGNAL(requestRunCommand(QString)), this, SLOT(runCommand(QString)));
 }
 
 void CantorPart::loadAssistants()
 {
     qDebug()<<"loading assistants...";
 
     QStringList assistantDirs;
     for (const QString& dir : QCoreApplication::libraryPaths())
         assistantDirs << dir + QDir::separator() + QLatin1String("cantor/assistants");
 
     QPluginLoader loader;
     for (const QString& dir : assistantDirs) {
 
         qDebug() << "dir: " << dir;
         QStringList assistants;
         QDir assistantDir = QDir(dir);
 
         assistants = assistantDir.entryList();
 
         for (const QString& assistant : assistants) {
             if (assistant==QLatin1String(".") || assistant==QLatin1String(".."))
                 continue;
 
             loader.setFileName(dir + QDir::separator() + assistant);
 
             if (!loader.load()){
                 qDebug() << "Error while loading assistant: " << assistant;
                 continue;
             }
 
             KPluginFactory* factory = KPluginLoader(loader.fileName()).factory();
             Cantor::Assistant* plugin = factory->create<Cantor::Assistant>(this);
 
             Cantor::Backend* backend=worksheet()->session()->backend();
 
             KPluginMetaData info(loader);
             plugin->setPluginInfo(info);
             plugin->setBackend(backend);
 
             bool supported=true;
             for (const QString& req : plugin->requiredExtensions())
                 supported=supported && backend->extensions().contains(req);
 
             if(supported)
             {
                 qDebug() << "plugin " << info.name() << " is supported by " << backend->name() << ", requires extensions " << plugin->requiredExtensions();
                 plugin->initActions();
                 connect(plugin, SIGNAL(requested()), this, SLOT(runAssistant()));
             }else
             {
                 qDebug() << "plugin " << info.name() << " is not supported by "<<backend->name();
                 removeChildClient(plugin);
                 plugin->deleteLater();
             }
         }
     }
 }
 
 void CantorPart::runAssistant()
 {
     Cantor::Assistant* a=qobject_cast<Cantor::Assistant*>(sender());
     QStringList cmds=a->run(widget());
     qDebug()<<cmds;
     if(!cmds.isEmpty())
         runCommand(cmds.join(QLatin1String("\n")));
 }
 
 void CantorPart::runCommand(const QString& cmd)
 {
     m_worksheet->appendCommandEntry(cmd);
 }
 
 void CantorPart::showSearchBar()
 {
     if (!m_searchBar) {
         m_searchBar = new SearchBar(widget(), m_worksheet);
         widget()->layout()->addWidget(m_searchBar);
         connect(m_searchBar, SIGNAL(destroyed(QObject*)),
                 this, SLOT(searchBarDeleted()));
     }
 
     m_findNext->setEnabled(true);
     m_findPrev->setEnabled(true);
 
     m_searchBar->showStandard();
     m_searchBar->setFocus();
 }
 
 void CantorPart::showExtendedSearchBar()
 {
     if (!m_searchBar) {
         m_searchBar = new SearchBar(widget(), m_worksheet);
         widget()->layout()->addWidget(m_searchBar);
         connect(m_searchBar, SIGNAL(destroyed(QObject*)),
                 this, SLOT(searchBarDeleted()));
     }
 
     m_findNext->setEnabled(true);
     m_findPrev->setEnabled(true);
 
     m_searchBar->showExtended();
     m_searchBar->setFocus();
 }
 
 void CantorPart::findNext()
 {
     if (m_searchBar)
         m_searchBar->next();
 }
 
 void CantorPart::findPrev()
 {
     if (m_searchBar)
         m_searchBar->prev();
 }
 
 void CantorPart::searchBarDeleted()
 {
     m_searchBar = nullptr;
     m_findNext->setEnabled(false);
     m_findPrev->setEnabled(false);
 }
 
 void CantorPart::adjustGuiToSession()
 {
     Cantor::Backend::Capabilities capabilities = m_worksheet->session()->backend()->capabilities();
 #ifdef WITH_EPS
     m_typeset->setVisible(capabilities.testFlag(Cantor::Backend::LaTexOutput));
 #else
     m_typeset->setVisible(false);
 #endif
     m_completion->setVisible(capabilities.testFlag(Cantor::Backend::Completion));
 
     //this is 0 on the first call
     if(m_showBackendHelp)
         m_showBackendHelp->setText(i18n("Show %1 Help", m_worksheet->session()->backend()->name()));
 }
 
 void CantorPart::publishWorksheet()
 {
     int ret = KMessageBox::questionYesNo(widget(),
                                          i18n("Do you want to upload current Worksheet to public web server?"),
                                          i18n("Question - Cantor"));
     if (ret != KMessageBox::Yes) return;
 
     if (isModified()||url().isEmpty())
     {
         ret = KMessageBox::warningContinueCancel(widget(),
                                                  i18n("The Worksheet is not saved. You should save it before uploading."),
                                                  i18n("Warning - Cantor"),  KStandardGuiItem::save(),  KStandardGuiItem::cancel());
         if (ret != KMessageBox::Continue) return;
         if (!saveFile()) return;
     }
 
     qDebug()<<"uploading file "<<url();
 
     // upload
     //HACK: use different .knsrc files for each category
     //remove this once KNS3 gains the ability to select category
     KNS3::UploadDialog dialog(QString::fromLatin1("cantor_%1.knsrc").arg(m_worksheet->session()->backend()->id().toLower()), widget());
     dialog.setUploadFile(url());
     dialog.exec();
 }
 
 void CantorPart::print()
 {
     QPrinter printer;
     QPointer<QPrintDialog> dialog = new QPrintDialog(&printer,  widget());
 
     // TODO: Re-enable print selection
     //if (m_worksheet->textCursor().hasSelection())
     //    dialog->addEnabledOption(QAbstractPrintDialog::PrintSelection);
 
     if (dialog->exec() == QDialog::Accepted)
         m_worksheet->print(&printer);
 
     delete dialog;
 }
 
 void CantorPart::printPreview()
 {
     QPrintPreviewDialog *dialog = new QPrintPreviewDialog(widget());
     connect(dialog, SIGNAL(paintRequested(QPrinter*)), m_worksheet, SLOT(print(QPrinter*)));
     dialog->exec();
 }
 
 void CantorPart::showScriptEditor(bool show)
 {
     if(show)
     {
         if (m_scriptEditor)
         {
             return;
         }
         Cantor::ScriptExtension* scriptE=dynamic_cast<Cantor::ScriptExtension*>(m_worksheet->session()->backend()->extension(QLatin1String("ScriptExtension")));
         if (!scriptE)
         {
             return;
         }
         m_scriptEditor=new ScriptEditorWidget(scriptE->scriptFileFilter(), scriptE->highlightingMode(), widget()->window());
         connect(m_scriptEditor, SIGNAL(runScript(QString)), this, SLOT(runScript(QString)));
         connect(m_scriptEditor, SIGNAL(destroyed()), this, SLOT(scriptEditorClosed()));
         m_scriptEditor->show();
     }else
     {
         m_scriptEditor->deleteLater();
     }
 }
 
 void CantorPart::scriptEditorClosed()
 {
     QAction* showEditor = actionCollection()->action(QLatin1String("show_editor"));
     if (showEditor)
     {
         showEditor->setChecked(false);
     }
 }
 
 void CantorPart::runScript(const QString& file)
 {
     Cantor::Backend* backend=m_worksheet->session()->backend();
     if(!backend->extensions().contains(QLatin1String("ScriptExtension")))
     {
         KMessageBox::error(widget(), i18n("This backend does not support scripts."), i18n("Error - Cantor"));
         return;
     }
 
     Cantor::ScriptExtension* scriptE=dynamic_cast<Cantor::ScriptExtension*>(backend->extension(QLatin1String("ScriptExtension")));
     m_worksheet->appendCommandEntry(scriptE->runExternalScript(file));
 }
 
 void CantorPart::blockStatusBar()
 {
     m_statusBarBlocked=true;
 }
 
 void CantorPart::unblockStatusBar()
 {
     m_statusBarBlocked=false;
     if(!m_cachedStatusMessage.isNull())
         setStatusMessage(m_cachedStatusMessage);
     m_cachedStatusMessage.clear();
 }
 
 void CantorPart::setStatusMessage(const QString& message)
 {
     if(!m_statusBarBlocked)
         emit setStatusBarText(message);
     else
         m_cachedStatusMessage=message;
 }
 
 void CantorPart::showImportantStatusMessage(const QString& message)
 {
     setStatusMessage(message);
     blockStatusBar();
     QTimer::singleShot(3000, this, SLOT(unblockStatusBar()));
 }
 
 K_PLUGIN_FACTORY_WITH_JSON(CantorPartFactory, "cantor_part.json", registerPlugin<CantorPart>();)
 #include "cantor_part.moc"
diff --git a/src/cantor_part.h b/src/cantor_part.h
index 67d40ea2..f35cdf89 100644
--- a/src/cantor_part.h
+++ b/src/cantor_part.h
@@ -1,184 +1,185 @@
 /*
     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.
 
     ---
     Copyright (C) 2009 Alexander Rieder <alexanderrieder@gmail.com>
 */
 
 #ifndef CANTORPART_H
 #define CANTORPART_H
 
 #include <QPointer>
 #include <QVector>
 
 #include <KParts/ReadWritePart>
 #include <lib/session.h>
 
 class QWidget;
 class Worksheet;
 class WorksheetView;
 class SarchBar;
 class SearchBar;
 class ScriptEditorWidget;
 class KAboutData;
 class QAction;
 class KToggleAction;
 class QProgressDialog;
 
 namespace Cantor{
     class PanelPluginHandler;
 }
 
 /**
  * This is a "Part".  It that does all the real work in a KPart
  * application.
  *
  * @short Main Part
  * @author Alexander Rieder <alexanderrieder@gmail.com>
  */
 class CantorPart : public KParts::ReadWritePart
 {
     Q_OBJECT
 public:
     /**
      * Default constructor
      */
     CantorPart(QWidget *parentWidget,QObject *parent, const QVariantList &args);
 
     /**
      * Destructor
      */
     ~CantorPart() override;
 
     /**
      * This is a virtual function inherited from KParts::ReadWritePart.
      * A shell will use this to inform this Part if it should act
      * read-only
      */
     void setReadWrite(bool rw) override;
 
     /**
      * Reimplemented to disable and enable Save action
      */
     void setModified(bool modified) override;
 
     KAboutData& createAboutData();
 
     Worksheet* worksheet();
 
 Q_SIGNALS:
     void setCaption(const QString& caption, const QIcon& icon);
     void showHelp(const QString& help);
 
 protected:
     /**
      * This must be implemented by each part
      */
     bool openFile() override;
 
     /**
      * This must be implemented by each read-write part
      */
     bool saveFile() override;
 
     /**
      * Called when this part becomes the active one,
      * or if it looses activity
      **/
     void guiActivateEvent( KParts::GUIActivateEvent * event ) override;
 
 
     void loadAssistants();
     void adjustGuiToSession();
 
     void setReadOnly();
 
 protected Q_SLOTS:
     void fileSaveAs();
     void fileSavePlain();
     void exportToLatex();
     void evaluateOrInterrupt();
     void restartBackend();
     void enableTypesetting(bool enable);
     void showBackendHelp();
     void print();
     void printPreview();
 
     void worksheetStatusChanged(Cantor::Session::Status stauts);
     void showSessionError(const QString& error);
     void worksheetSessionLoginStarted();
     void worksheetSessionLoginDone();
     void initialized();
     void updateCaption();
 
     void pluginsChanged();
     void runCommand(const QString& value);
 
     void runAssistant();
     void publishWorksheet();
 
     void showScriptEditor(bool show);
     void scriptEditorClosed();
     void runScript(const QString& file);
 
     void showSearchBar();
     void showExtendedSearchBar();
     void findNext();
     void findPrev();
     void searchBarDeleted();
 
     /** sets the status message, or cached it, if the StatusBar is blocked.
      *  Use this method instead of "emit setStatusBarText"
      */
     void setStatusMessage(const QString& message);
     /** Shows an important status message. It makes sure the message is displayed,
      *  by blocking the statusbarText for 3 seconds
      */
     void showImportantStatusMessage(const QString& message);
     /** Blocks the StatusBar for new messages, so the currently shown one won't be overridden
      */
     void blockStatusBar();
     /** Removes the block from the StatusBar, and shows the last one of the StatusMessages that
         where set during the block
     **/
     void unblockStatusBar();
 private:
     Worksheet *m_worksheet;
     WorksheetView *m_worksheetview;
     SearchBar *m_searchBar;
     QPointer<ScriptEditorWidget> m_scriptEditor;
     Cantor::PanelPluginHandler* m_panelHandler;
 
     QProgressDialog* m_initProgressDlg;
     bool m_showProgressDlg;
     QAction * m_evaluate;
+    QAction * m_restart;
     QAction * m_save;
     QAction * m_findNext;
     QAction * m_findPrev;
     KToggleAction* m_typeset;
     KToggleAction* m_highlight;
     KToggleAction* m_completion;
     KToggleAction* m_exprNumbering;
     KToggleAction* m_animateWorksheet;
     QAction * m_showBackendHelp;
     QVector<QAction*> m_editActions;
 
     QString m_cachedStatusMessage;
     bool m_statusBarBlocked;
     unsigned int m_sessionStatusCounter;
 };
 
 #endif // CANTORPART_H