diff --git a/src/Gui/Clipping.cpp b/src/Gui/Clipping.cpp
index 1a30c4bb63..76d075a138 100644
--- a/src/Gui/Clipping.cpp
+++ b/src/Gui/Clipping.cpp
@@ -106,6 +106,8 @@ Clipping::Clipping(Gui::View3DInventor* view, QWidget* parent)
 {
     // create widgets
     d->ui.setupUi(this);
+    setupConnections();
+
     d->ui.clipView->setRange(-INT_MAX,INT_MAX);
     d->ui.clipView->setSingleStep(0.1f);
     d->ui.clipX->setRange(-INT_MAX,INT_MAX);
@@ -207,6 +209,42 @@ Clipping::~Clipping()
     delete d;
 }
 
+void Clipping::setupConnections()
+{
+    connect(d->ui.groupBoxX, &QGroupBox::toggled,
+            this, &Clipping::onGroupBoxXToggled);
+    connect(d->ui.groupBoxY, &QGroupBox::toggled,
+            this, &Clipping::onGroupBoxYToggled);
+    connect(d->ui.groupBoxZ, &QGroupBox::toggled,
+            this, &Clipping::onGroupBoxZToggled);
+    connect(d->ui.clipX, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onClipXValueChanged);
+    connect(d->ui.clipY, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onClipYValueChanged);
+    connect(d->ui.clipZ, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onClipZValueChanged);
+    connect(d->ui.flipClipX, &QPushButton::clicked,
+            this, &Clipping::onFlipClipXClicked);
+    connect(d->ui.flipClipY, &QPushButton::clicked,
+            this, &Clipping::onFlipClipYClicked);
+    connect(d->ui.flipClipZ, &QPushButton::clicked,
+            this, &Clipping::onFlipClipZClicked);
+    connect(d->ui.groupBoxView, &QGroupBox::toggled,
+            this, &Clipping::onGroupBoxViewToggled);
+    connect(d->ui.clipView, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onClipViewValueChanged);
+    connect(d->ui.fromView, &QPushButton::clicked,
+            this, &Clipping::onFromViewClicked);
+    connect(d->ui.adjustViewdirection, &QCheckBox::toggled,
+            this, &Clipping::onAdjustViewdirectionToggled);
+    connect(d->ui.dirX, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onDirXValueChanged);
+    connect(d->ui.dirY, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onDirYValueChanged);
+    connect(d->ui.dirZ, qOverload<double>(&QDoubleSpinBox::valueChanged),
+            this, &Clipping::onDirZValueChanged);
+}
+
 void Clipping::reject()
 {
     QDialog::reject();
@@ -216,7 +254,7 @@ void Clipping::reject()
     }
 }
 
-void Clipping::on_groupBoxX_toggled(bool on)
+void Clipping::onGroupBoxXToggled(bool on)
 {
     if (on) {
         d->ui.groupBoxView->setChecked(false);
@@ -225,7 +263,7 @@ void Clipping::on_groupBoxX_toggled(bool on)
     d->clipX->on.setValue(on);
 }
 
-void Clipping::on_groupBoxY_toggled(bool on)
+void Clipping::onGroupBoxYToggled(bool on)
 {
     if (on) {
         d->ui.groupBoxView->setChecked(false);
@@ -234,7 +272,7 @@ void Clipping::on_groupBoxY_toggled(bool on)
     d->clipY->on.setValue(on);
 }
 
-void Clipping::on_groupBoxZ_toggled(bool on)
+void Clipping::onGroupBoxZToggled(bool on)
 {
     if (on) {
         d->ui.groupBoxView->setChecked(false);
@@ -243,46 +281,46 @@ void Clipping::on_groupBoxZ_toggled(bool on)
     d->clipZ->on.setValue(on);
 }
 
-void Clipping::on_clipX_valueChanged(double val)
+void Clipping::onClipXValueChanged(double val)
 {
     SbPlane pln = d->clipX->plane.getValue();
     d->clipX->plane.setValue(SbPlane(pln.getNormal(),d->flipX ? -val : val));
 }
 
-void Clipping::on_clipY_valueChanged(double val)
+void Clipping::onClipYValueChanged(double val)
 {
     SbPlane pln = d->clipY->plane.getValue();
     d->clipY->plane.setValue(SbPlane(pln.getNormal(),d->flipY ? -val : val));
 }
 
-void Clipping::on_clipZ_valueChanged(double val)
+void Clipping::onClipZValueChanged(double val)
 {
     SbPlane pln = d->clipZ->plane.getValue();
     d->clipZ->plane.setValue(SbPlane(pln.getNormal(),d->flipZ ? -val : val));
 }
 
-void Clipping::on_flipClipX_clicked()
+void Clipping::onFlipClipXClicked()
 {
     d->flipX = !d->flipX;
     SbPlane pln = d->clipX->plane.getValue();
     d->clipX->plane.setValue(SbPlane(-pln.getNormal(),-pln.getDistanceFromOrigin()));
 }
 
-void Clipping::on_flipClipY_clicked()
+void Clipping::onFlipClipYClicked()
 {
     d->flipY = !d->flipY;
     SbPlane pln = d->clipY->plane.getValue();
     d->clipY->plane.setValue(SbPlane(-pln.getNormal(),-pln.getDistanceFromOrigin()));
 }
 
-void Clipping::on_flipClipZ_clicked()
+void Clipping::onFlipClipZClicked()
 {
     d->flipZ = !d->flipZ;
     SbPlane pln = d->clipZ->plane.getValue();
     d->clipZ->plane.setValue(SbPlane(-pln.getNormal(),-pln.getDistanceFromOrigin()));
 }
 
-void Clipping::on_groupBoxView_toggled(bool on)
+void Clipping::onGroupBoxViewToggled(bool on)
 {
     if (on) {
         d->ui.groupBoxX->setChecked(false);
@@ -293,13 +331,13 @@ void Clipping::on_groupBoxView_toggled(bool on)
     d->clipView->on.setValue(on);
 }
 
-void Clipping::on_clipView_valueChanged(double val)
+void Clipping::onClipViewValueChanged(double val)
 {
     SbPlane pln = d->clipView->plane.getValue();
     d->clipView->plane.setValue(SbPlane(pln.getNormal(),val));
 }
 
-void Clipping::on_fromView_clicked()
+void Clipping::onFromViewClicked()
 {
     if (d->view) {
         Gui::View3DInventorViewer* view = d->view->getViewer();
@@ -309,7 +347,7 @@ void Clipping::on_fromView_clicked()
     }
 }
 
-void Clipping::on_adjustViewdirection_toggled(bool on)
+void Clipping::onAdjustViewdirectionToggled(bool on)
 {
     d->ui.dirX->setDisabled(on);
     d->ui.dirY->setDisabled(on);
@@ -322,7 +360,7 @@ void Clipping::on_adjustViewdirection_toggled(bool on)
         d->sensor->unschedule();
 }
 
-void Clipping::on_dirX_valueChanged(double)
+void Clipping::onDirXValueChanged(double)
 {
     double x = d->ui.dirX->value();
     double y = d->ui.dirY->value();
@@ -334,7 +372,7 @@ void Clipping::on_dirX_valueChanged(double)
         d->clipView->plane.setValue(SbPlane(normal,pln.getDistanceFromOrigin()));
 }
 
-void Clipping::on_dirY_valueChanged(double)
+void Clipping::onDirYValueChanged(double)
 {
     double x = d->ui.dirX->value();
     double y = d->ui.dirY->value();
@@ -346,7 +384,7 @@ void Clipping::on_dirY_valueChanged(double)
         d->clipView->plane.setValue(SbPlane(normal,pln.getDistanceFromOrigin()));
 }
 
-void Clipping::on_dirZ_valueChanged(double)
+void Clipping::onDirZValueChanged(double)
 {
     double x = d->ui.dirX->value();
     double y = d->ui.dirY->value();
diff --git a/src/Gui/Clipping.h b/src/Gui/Clipping.h
index 6a104148e8..7737be1f16 100644
--- a/src/Gui/Clipping.h
+++ b/src/Gui/Clipping.h
@@ -25,6 +25,7 @@
 #define GUI_DIALOG_CLIPPING_H
 
 #include <QDialog>
+#include <FCGlobal.h>
 
 namespace Gui {
 class View3DInventor;
@@ -42,23 +43,24 @@ public:
     Clipping(Gui::View3DInventor* view, QWidget* parent = nullptr);
     ~Clipping();
 
-protected Q_SLOTS:
-    void on_groupBoxX_toggled(bool);
-    void on_groupBoxY_toggled(bool);
-    void on_groupBoxZ_toggled(bool);
-    void on_clipX_valueChanged(double);
-    void on_clipY_valueChanged(double);
-    void on_clipZ_valueChanged(double);
-    void on_flipClipX_clicked();
-    void on_flipClipY_clicked();
-    void on_flipClipZ_clicked();
-    void on_groupBoxView_toggled(bool);
-    void on_clipView_valueChanged(double);
-    void on_fromView_clicked();
-    void on_adjustViewdirection_toggled(bool);
-    void on_dirX_valueChanged(double);
-    void on_dirY_valueChanged(double);
-    void on_dirZ_valueChanged(double);
+protected:
+    void setupConnections();
+    void onGroupBoxXToggled(bool);
+    void onGroupBoxYToggled(bool);
+    void onGroupBoxZToggled(bool);
+    void onClipXValueChanged(double);
+    void onClipYValueChanged(double);
+    void onClipZValueChanged(double);
+    void onFlipClipXClicked();
+    void onFlipClipYClicked();
+    void onFlipClipZClicked();
+    void onGroupBoxViewToggled(bool);
+    void onClipViewValueChanged(double);
+    void onFromViewClicked();
+    void onAdjustViewdirectionToggled(bool);
+    void onDirXValueChanged(double);
+    void onDirYValueChanged(double);
+    void onDirZValueChanged(double);
 
 public:
     void reject();
diff --git a/src/Gui/DemoMode.cpp b/src/Gui/DemoMode.cpp
index 7774d29857..e0cd425b63 100644
--- a/src/Gui/DemoMode.cpp
+++ b/src/Gui/DemoMode.cpp
@@ -47,6 +47,7 @@ DemoMode::DemoMode(QWidget* /*parent*/, Qt::WindowFlags fl)
 {
     // create widgets
     ui->setupUi(this);
+    setupConnections();
     ui->playButton->setCheckable(true);
 
     timer = new QTimer(this);
@@ -66,9 +67,25 @@ DemoMode::~DemoMode()
     delete ui;
 }
 
+void DemoMode::setupConnections()
+{
+    connect(ui->playButton, &QPushButton::clicked,
+            this, &DemoMode::onPlayButtonToggled);
+    connect(ui->fullscreen, &QCheckBox::toggled,
+            this, &DemoMode::onFullscreenToggled);
+    connect(ui->timerCheck, &QCheckBox::toggled,
+            this, &DemoMode::onTimerCheckToggled);
+    connect(ui->speedSlider, &QSlider::valueChanged,
+            this, &DemoMode::onSpeedSliderValueChanged);
+    connect(ui->angleSlider, &QSlider::valueChanged,
+            this, &DemoMode::onAngleSliderValueChanged);
+    connect(ui->timeout, qOverload<int>(&QSpinBox::valueChanged),
+            this, &DemoMode::onTimeoutValueChanged);
+}
+
 void DemoMode::reset()
 {
-    on_fullscreen_toggled(false);
+    onFullscreenToggled(false);
     Gui::View3DInventor* view = activeView();
     if (view)
         view->getViewer()->stopAnimating();
@@ -152,7 +169,7 @@ SbVec3f DemoMode::getDirection(Gui::View3DInventor* view) const
     return vec;
 }
 
-void DemoMode::on_angleSlider_valueChanged(int v)
+void DemoMode::onAngleSliderValueChanged(int v)
 {
     Gui::View3DInventor* view = activeView();
     if (view) {
@@ -185,7 +202,7 @@ void DemoMode::reorientCamera(SoCamera * cam, const SbRotation & rot)
     cam->position = focalpoint - cam->focalDistance.getValue() * direction;
 }
 
-void DemoMode::on_speedSlider_valueChanged(int v)
+void DemoMode::onSpeedSliderValueChanged(int v)
 {
     Q_UNUSED(v);
     Gui::View3DInventor* view = activeView();
@@ -194,7 +211,7 @@ void DemoMode::on_speedSlider_valueChanged(int v)
     }
 }
 
-void DemoMode::on_playButton_toggled(bool pressed)
+void DemoMode::onPlayButtonToggled(bool pressed)
 {
     Gui::View3DInventor* view = activeView();
     if (view) {
@@ -218,7 +235,7 @@ void DemoMode::on_playButton_toggled(bool pressed)
     }
 }
 
-void DemoMode::on_fullscreen_toggled(bool on)
+void DemoMode::onFullscreenToggled(bool on)
 {
     Gui::View3DInventor* view = activeView();
     if (view) {
@@ -238,7 +255,7 @@ void DemoMode::on_fullscreen_toggled(bool on)
     }
 }
 
-void DemoMode::on_timeout_valueChanged(int v)
+void DemoMode::onTimeoutValueChanged(int v)
 {
     timer->setInterval(v * 1000);
 }
@@ -259,7 +276,7 @@ void DemoMode::startAnimation(Gui::View3DInventor* view)
         getSpeed(ui->speedSlider->value()));
 }
 
-void DemoMode::on_timerCheck_toggled(bool on)
+void DemoMode::onTimerCheckToggled(bool on)
 {
     if (on)
         timer->start();
diff --git a/src/Gui/DemoMode.h b/src/Gui/DemoMode.h
index 284772113b..f13c7bd25e 100644
--- a/src/Gui/DemoMode.h
+++ b/src/Gui/DemoMode.h
@@ -24,10 +24,12 @@
 #define GUI_DIALOG_DEMOMODE_H
 
 #include <QDialog>
+#include <FCGlobal.h>
 
 
 class QTimer;
 class SoCamera;
+class SbVec3f;
 class SbRotation;
 
 namespace Gui {
@@ -49,13 +51,14 @@ public:
     void accept();
     void reject();
 
-protected Q_SLOTS:
-    void on_playButton_toggled(bool);
-    void on_fullscreen_toggled(bool);
-    void on_timerCheck_toggled(bool);
-    void on_speedSlider_valueChanged(int);
-    void on_angleSlider_valueChanged(int);
-    void on_timeout_valueChanged(int);
+protected:
+    void setupConnections();
+    void onPlayButtonToggled(bool);
+    void onFullscreenToggled(bool);
+    void onTimerCheckToggled(bool);
+    void onSpeedSliderValueChanged(int);
+    void onAngleSliderValueChanged(int);
+    void onTimeoutValueChanged(int);
     void onAutoPlay();
 
 private:
diff --git a/src/Gui/DlgOnlineHelpImp.cpp b/src/Gui/DlgOnlineHelpImp.cpp
index 1fe6dff3ed..aa3749c0a6 100644
--- a/src/Gui/DlgOnlineHelpImp.cpp
+++ b/src/Gui/DlgOnlineHelpImp.cpp
@@ -97,7 +97,7 @@ void DlgOnlineHelpImp::changeEvent(QEvent *e)
     }
 }
 
-void DlgOnlineHelpImp::on_lineEditDownload_fileNameSelected( const QString& url )
+void DlgOnlineHelpImp::onLineEditDownloadFileNameSelected( const QString& url )
 {
     QDir dir(url);
     if (dir.exists() && dir.count() == 0) {
diff --git a/src/Gui/DlgOnlineHelpImp.h b/src/Gui/DlgOnlineHelpImp.h
index 6a7c4a4e70..947d4c1297 100644
--- a/src/Gui/DlgOnlineHelpImp.h
+++ b/src/Gui/DlgOnlineHelpImp.h
@@ -53,7 +53,7 @@ protected:
     void changeEvent(QEvent *e) override;
 
 protected:
-    void on_lineEditDownload_fileNameSelected(const QString&);
+    void onLineEditDownloadFileNameSelected(const QString&);
 
 private:
     std::unique_ptr<Ui_DlgOnlineHelp> ui;
diff --git a/src/Gui/DocumentRecovery.cpp b/src/Gui/DocumentRecovery.cpp
index aa7eafc435..fd64b87cbe 100644
--- a/src/Gui/DocumentRecovery.cpp
+++ b/src/Gui/DocumentRecovery.cpp
@@ -175,6 +175,8 @@ DocumentRecovery::DocumentRecovery(const QList<QFileInfo>& dirs, QWidget* parent
   : QDialog(parent), d_ptr(new DocumentRecoveryPrivate())
 {
     d_ptr->ui.setupUi(this);
+    connect(d_ptr->ui.buttonCleanup, &QPushButton::clicked,
+            this, &DocumentRecovery::onButtonCleanupClicked);
     d_ptr->ui.buttonBox->button(QDialogButtonBox::Ok)->setText(tr("Start Recovery"));
     d_ptr->ui.treeWidget->header()->setSectionResizeMode(QHeaderView::Stretch);
 
@@ -535,7 +537,7 @@ void DocumentRecovery::onDeleteSection()
     }
 }
 
-void DocumentRecovery::on_buttonCleanup_clicked()
+void DocumentRecovery::onButtonCleanupClicked()
 {
     QMessageBox msgBox(this);
     msgBox.setIcon(QMessageBox::Warning);
diff --git a/src/Gui/DocumentRecovery.h b/src/Gui/DocumentRecovery.h
index 46fb2696b5..2601503e09 100644
--- a/src/Gui/DocumentRecovery.h
+++ b/src/Gui/DocumentRecovery.h
@@ -55,8 +55,8 @@ protected:
     QString createProjectFile(const QString&);
     void cleanup(QDir&, const QList<QFileInfo>&, const QString&);
 
-protected Q_SLOTS:
-    void on_buttonCleanup_clicked();
+protected:
+    void onButtonCleanupClicked();
     void onDeleteSection();
 
 private:
diff --git a/src/Gui/InputVector.cpp b/src/Gui/InputVector.cpp
index e8c22df47b..0e8b1a767c 100644
--- a/src/Gui/InputVector.cpp
+++ b/src/Gui/InputVector.cpp
@@ -75,7 +75,7 @@ LocationWidget::LocationWidget (QWidget * parent)
     gridLayout->addLayout(box, 0, 0, 1, 2);
 
     connect(dValue, qOverload<int>(&QComboBox::activated),
-            this, &LocationWidget::on_direction_activated);
+            this, &LocationWidget::onDirectionActivated);
     retranslateUi();
 }
 
@@ -202,7 +202,7 @@ Base::Vector3d LocationWidget::getUserDirection(bool* ok) const
     return dir;
 }
 
-void LocationWidget::on_direction_activated(int index)
+void LocationWidget::onDirectionActivated(int index)
 {
     // last item is selected to define direction by user
     if (index+1 == dValue->count()) {
@@ -253,7 +253,7 @@ Base::Vector3d LocationDialog::getUserDirection(bool* ok) const
     return dir;
 }
 
-void LocationDialog::on_direction_activated(int index)
+void LocationDialog::onDirectionActivated(int index)
 {
     directionActivated(index);
 }
diff --git a/src/Gui/InputVector.h b/src/Gui/InputVector.h
index 48f0763ec9..444898d67b 100644
--- a/src/Gui/InputVector.h
+++ b/src/Gui/InputVector.h
@@ -52,8 +52,8 @@ public:
     Base::Vector3d getDirection() const;
     Base::Vector3d getUserDirection(bool* ok=nullptr) const;
 
-private Q_SLOTS:
-    void on_direction_activated(int);
+private:
+    void onDirectionActivated(int);
 
 private:
     void changeEvent(QEvent*) override;
@@ -86,8 +86,8 @@ protected:
 protected:
     void changeEvent(QEvent *e) override = 0;
 
-private Q_SLOTS:
-    void on_direction_activated(int);
+private:
+    void onDirectionActivated(int);
 
 public:
     virtual Base::Vector3d getDirection() const = 0;
diff --git a/src/Gui/SceneInspector.cpp b/src/Gui/SceneInspector.cpp
index 8871979d6d..2a8b3d3bd5 100644
--- a/src/Gui/SceneInspector.cpp
+++ b/src/Gui/SceneInspector.cpp
@@ -135,6 +135,8 @@ DlgInspector::DlgInspector(QWidget* parent, Qt::WindowFlags fl)
   : QDialog(parent, fl), ui(new Ui_SceneInspector())
 {
     ui->setupUi(this);
+    connect(ui->refreshButton, &QPushButton::clicked,
+            this, &DlgInspector::onRefreshButtonClicked);
     setWindowTitle(tr("Scene Inspector"));
 
     auto model = new SceneModel(this);
@@ -208,7 +210,7 @@ void DlgInspector::changeEvent(QEvent *e)
     QDialog::changeEvent(e);
 }
 
-void DlgInspector::on_refreshButton_clicked()
+void DlgInspector::onRefreshButtonClicked()
 {
     Gui::Document* doc = Application::Instance->activeDocument();
     if (doc) {
diff --git a/src/Gui/SceneInspector.h b/src/Gui/SceneInspector.h
index 8857cc3b16..a6812a1f61 100644
--- a/src/Gui/SceneInspector.h
+++ b/src/Gui/SceneInspector.h
@@ -76,8 +76,8 @@ public:
 
     void setDocument(Gui::Document* doc);
 
-private Q_SLOTS:
-    void on_refreshButton_clicked();
+private:
+    void onRefreshButtonClicked();
 
 protected:
     void changeEvent(QEvent *e) override;
diff --git a/src/Gui/Splashscreen.cpp b/src/Gui/Splashscreen.cpp
index a2f4062877..2e3439dc97 100644
--- a/src/Gui/Splashscreen.cpp
+++ b/src/Gui/Splashscreen.cpp
@@ -243,6 +243,8 @@ AboutDialog::AboutDialog(bool showLic, QWidget* parent)
 
     setModal(true);
     ui->setupUi(this);
+    connect(ui->copyButton, &QPushButton::clicked,
+            this, &AboutDialog::copyToClipboard);
 
     // remove the automatic help button in dialog title since we don't use it
     setWindowFlag(Qt::WindowContextHelpButtonHint, false);
@@ -718,7 +720,7 @@ void AboutDialog::linkActivated(const QUrl& link)
     licenseView->setSource(link);
 }
 
-void AboutDialog::on_copyButton_clicked()
+void AboutDialog::copyToClipboard()
 {
     QString data;
     QTextStream str(&data);
diff --git a/src/Gui/Splashscreen.h b/src/Gui/Splashscreen.h
index a0368184f5..bc68ccccb4 100644
--- a/src/Gui/Splashscreen.h
+++ b/src/Gui/Splashscreen.h
@@ -107,8 +107,8 @@ protected:
     void showCollectionInformation();
     void showOrHideImage(const QRect& rect);
 
-protected Q_SLOTS:
-    virtual void on_copyButton_clicked();
+protected:
+    virtual void copyToClipboard();
     void linkActivated(const QUrl& link);
 
 private:
diff --git a/src/Gui/TaskElementColors.cpp b/src/Gui/TaskElementColors.cpp
index 605af83848..8ff6d4d2d8 100644
--- a/src/Gui/TaskElementColors.cpp
+++ b/src/Gui/TaskElementColors.cpp
@@ -313,18 +313,22 @@ ElementColors::ElementColors(ViewProviderDocumentObject* vp, bool noHide)
     :d(new Private(vp))
 {
     d->ui->setupUi(this);
+    setupConnections();
+
     d->ui->objectLabel->setText(QString::fromUtf8(vp->getObject()->Label.getValue()));
     d->ui->elementList->setMouseTracking(true); // needed for itemEntered() to work
 
-    if(noHide)
+    if (noHide) {
         d->ui->hideSelection->setVisible(false);
+    }
 
     ParameterGrp::handle hPart = App::GetApplication().GetParameterGroupByPath
         ("User parameter:BaseApp/Preferences/View");
     d->ui->recompute->setChecked(hPart->GetBool("ColorRecompute",true));
     d->ui->onTop->setChecked(hPart->GetBool("ColorOnTop",true));
-    if(d->ui->onTop->isChecked())
+    if (d->ui->onTop->isChecked()) {
         d->vpParent->OnTopWhenSelected.setValue(3);
+    }
 
     Selection().addSelectionGate(d, ResolveMode::NoResolve);
 
@@ -343,13 +347,39 @@ ElementColors::~ElementColors()
     Selection().rmvSelectionGate();
 }
 
-void ElementColors::on_recompute_clicked(bool checked) {
+void ElementColors::setupConnections()
+{
+    connect(d->ui->removeSelection, &QPushButton::clicked,
+            this, &ElementColors::onRemoveSelectionClicked);
+    connect(d->ui->addSelection, &QPushButton::clicked,
+            this, &ElementColors::onAddSelectionClicked);
+    connect(d->ui->removeAll, &QPushButton::clicked,
+            this, &ElementColors::onRemoveAllClicked);
+    connect(d->ui->elementList, &QListWidget::itemDoubleClicked,
+            this, &ElementColors::onElementListItemDoubleClicked);
+    connect(d->ui->elementList, &QListWidget::itemSelectionChanged,
+            this, &ElementColors::onElementListItemSelectionChanged);
+    connect(d->ui->elementList, &QListWidget::itemEntered,
+            this, &ElementColors::onElementListItemEntered);
+    connect(d->ui->recompute, &QCheckBox::clicked,
+            this, &ElementColors::onRecomputeClicked);
+    connect(d->ui->onTop, &QCheckBox::clicked,
+            this, &ElementColors::onTopClicked);
+    connect(d->ui->hideSelection, &QPushButton::clicked,
+            this, &ElementColors::onHideSelectionClicked);
+    connect(d->ui->boxSelect, &QPushButton::clicked,
+            this, &ElementColors::onBoxSelectClicked);
+}
+
+void ElementColors::onRecomputeClicked(bool checked)
+{
     ParameterGrp::handle hPart = App::GetApplication().GetParameterGroupByPath
         ("User parameter:BaseApp/Preferences/View");
     hPart->SetBool("ColorRecompute",checked);
 }
 
-void ElementColors::on_onTop_clicked(bool checked) {
+void ElementColors::onTopClicked(bool checked)
+{
     ParameterGrp::handle hPart = App::GetApplication().GetParameterGroupByPath
         ("User parameter:BaseApp/Preferences/View");
     hPart->SetBool("ColorOnTop",checked);
@@ -368,19 +398,19 @@ void ElementColors::slotDeleteObject(const ViewProvider& obj)
         Control().closeDialog();
 }
 
-void ElementColors::on_removeSelection_clicked()
+void ElementColors::onRemoveSelectionClicked()
 {
     d->removeItems();
 }
 
-void ElementColors::on_boxSelect_clicked()
+void ElementColors::onBoxSelectClicked()
 {
     auto cmd = Application::Instance->commandManager().getCommandByName("Std_BoxElementSelection");
     if(cmd)
         cmd->invoke(0);
 }
 
-void ElementColors::on_hideSelection_clicked() {
+void ElementColors::onHideSelectionClicked() {
     auto sels = Selection().getSelectionEx(d->editDoc.c_str(), App::DocumentObject::getClassTypeId(), ResolveMode::NoResolve);
     for(auto &sel : sels) {
         if(d->editObj!=sel.getFeatName())
@@ -400,7 +430,7 @@ void ElementColors::on_hideSelection_clicked() {
     }
 }
 
-void ElementColors::on_addSelection_clicked()
+void ElementColors::onAddSelectionClicked()
 {
     auto sels = Selection().getSelectionEx(d->editDoc.c_str(), App::DocumentObject::getClassTypeId(), ResolveMode::NoResolve);
     d->items.clear();
@@ -440,7 +470,7 @@ void ElementColors::on_addSelection_clicked()
     }
 }
 
-void ElementColors::on_removeAll_clicked()
+void ElementColors::onRemoveAllClicked()
 {
     d->removeAll();
 }
@@ -476,7 +506,7 @@ void ElementColors::leaveEvent(QEvent *e) {
     }
 }
 
-void ElementColors::on_elementList_itemEntered(QListWidgetItem *item) {
+void ElementColors::onElementListItemEntered(QListWidgetItem *item) {
     std::string name(qPrintable(item->data(Qt::UserRole+1).value<QString>()));
     if(!d->hiddenSub.empty()) {
         d->vp->partialRender({d->hiddenSub},false);
@@ -493,7 +523,7 @@ void ElementColors::on_elementList_itemEntered(QListWidgetItem *item) {
                                       : Gui::SelectionChanges::MsgSource::Internal);
 }
 
-void ElementColors::on_elementList_itemSelectionChanged() {
+void ElementColors::onElementListItemSelectionChanged() {
     d->onSelectionChanged();
 }
 
@@ -502,7 +532,7 @@ void ElementColors::onSelectionChanged(const SelectionChanges& msg)
     d->onSelectionChanged(msg);
 }
 
-void ElementColors::on_elementList_itemDoubleClicked(QListWidgetItem *item) {
+void ElementColors::onElementListItemDoubleClicked(QListWidgetItem *item) {
     d->editItem(this,item);
 }
 
diff --git a/src/Gui/TaskElementColors.h b/src/Gui/TaskElementColors.h
index 75cefc93ff..fd787eb661 100644
--- a/src/Gui/TaskElementColors.h
+++ b/src/Gui/TaskElementColors.h
@@ -44,17 +44,18 @@ public:
     bool accept();
     bool reject();
 
-private Q_SLOTS:
-    void on_removeSelection_clicked();
-    void on_addSelection_clicked();
-    void on_removeAll_clicked();
-    void on_elementList_itemDoubleClicked(QListWidgetItem *item);
-    void on_elementList_itemSelectionChanged();
-    void on_elementList_itemEntered(QListWidgetItem *item);
-    void on_recompute_clicked(bool checked);
-    void on_onTop_clicked(bool checked);
-    void on_hideSelection_clicked();
-    void on_boxSelect_clicked();
+private:
+    void setupConnections();
+    void onRemoveSelectionClicked();
+    void onAddSelectionClicked();
+    void onRemoveAllClicked();
+    void onElementListItemDoubleClicked(QListWidgetItem *item);
+    void onElementListItemSelectionChanged();
+    void onElementListItemEntered(QListWidgetItem *item);
+    void onRecomputeClicked(bool checked);
+    void onTopClicked(bool checked);
+    void onHideSelectionClicked();
+    void onBoxSelectClicked();
 
 protected:
     void onSelectionChanged(const SelectionChanges& msg) override;
diff --git a/src/Gui/TaskView/TaskAppearance.cpp b/src/Gui/TaskView/TaskAppearance.cpp
index b5d3613616..695686ef54 100644
--- a/src/Gui/TaskView/TaskAppearance.cpp
+++ b/src/Gui/TaskView/TaskAppearance.cpp
@@ -46,6 +46,8 @@ TaskAppearance::TaskAppearance(QWidget *parent)
     proxy = new QWidget(this);
     ui = new Ui_TaskAppearance();
     ui->setupUi(proxy);
+    setupConnections();
+
     ui->textLabel1_3->hide();
     ui->changePlot->hide();
     QMetaObject::connectSlotsByName(this);
@@ -65,6 +67,27 @@ TaskAppearance::~TaskAppearance()
     Gui::Selection().Detach(this);
 }
 
+void TaskAppearance::setupConnections()
+{
+#if QT_VERSION < QT_VERSION_CHECK(5, 14, 0)
+    connect(ui->changeMode, qOverload<const QString&>(&QComboBox::activated),
+            this, &TaskAppearance::onChangeModeActivated);
+    connect(ui->changePlot, qOverload<const QString&>(&QComboBox::activated),
+            this, &TaskAppearance::onChangePlotActivated);
+#else
+    connect(ui->changeMode, &QComboBox::textActivated,
+            this, &TaskAppearance::onChangeModeActivated);
+    connect(ui->changePlot, &QComboBox::textActivated,
+            this, &TaskAppearance::onChangePlotActivated);
+#endif
+    connect(ui->spinTransparency, qOverload<int>(&QSpinBox::valueChanged),
+            this, &TaskAppearance::onTransparencyValueChanged);
+    connect(ui->spinPointSize, qOverload<int>(&QSpinBox::valueChanged),
+            this, &TaskAppearance::onPointSizeValueChanged);
+    connect(ui->spinLineWidth, qOverload<int>(&QSpinBox::valueChanged),
+            this, &TaskAppearance::onLineWidthValueChanged);
+}
+
 void TaskAppearance::changeEvent(QEvent *e)
 {
     TaskBox::changeEvent(e);
@@ -132,7 +155,7 @@ void TaskAppearance::slotChangedObject(const Gui::ViewProvider& obj,
 /**
  * Sets the 'Display' property of all selected view providers.
  */
-void TaskAppearance::on_changeMode_activated(const QString& s)
+void TaskAppearance::onChangeModeActivated(const QString& s)
 {
     Gui::WaitCursor wc;
     std::vector<Gui::ViewProvider*> Provider = getSelection();
@@ -145,7 +168,7 @@ void TaskAppearance::on_changeMode_activated(const QString& s)
     }
 }
 
-void TaskAppearance::on_changePlot_activated(const QString&s)
+void TaskAppearance::onChangePlotActivated(const QString&s)
 {
     Base::Console().Log("Plot = %s\n",(const char*)s.toLatin1());
 }
@@ -153,7 +176,7 @@ void TaskAppearance::on_changePlot_activated(const QString&s)
 /**
  * Sets the 'Transparency' property of all selected view providers.
  */
-void TaskAppearance::on_spinTransparency_valueChanged(int transparency)
+void TaskAppearance::onTransparencyValueChanged(int transparency)
 {
     std::vector<Gui::ViewProvider*> Provider = getSelection();
     for (const auto & It : Provider) {
@@ -168,7 +191,7 @@ void TaskAppearance::on_spinTransparency_valueChanged(int transparency)
 /**
  * Sets the 'PointSize' property of all selected view providers.
  */
-void TaskAppearance::on_spinPointSize_valueChanged(int pointsize)
+void TaskAppearance::onPointSizeValueChanged(int pointsize)
 {
     std::vector<Gui::ViewProvider*> Provider = getSelection();
     for (const auto & It : Provider) {
@@ -183,7 +206,7 @@ void TaskAppearance::on_spinPointSize_valueChanged(int pointsize)
 /**
  * Sets the 'LineWidth' property of all selected view providers.
  */
-void TaskAppearance::on_spinLineWidth_valueChanged(int linewidth)
+void TaskAppearance::onLineWidthValueChanged(int linewidth)
 {
     std::vector<Gui::ViewProvider*> Provider = getSelection();
     for (const auto & It : Provider) {
diff --git a/src/Gui/TaskView/TaskAppearance.h b/src/Gui/TaskView/TaskAppearance.h
index 52d79c215c..30b0256924 100644
--- a/src/Gui/TaskView/TaskAppearance.h
+++ b/src/Gui/TaskView/TaskAppearance.h
@@ -52,11 +52,12 @@ public:
                   Gui::SelectionSingleton::MessageType Reason) override;
 
 private Q_SLOTS:
-    void on_changeMode_activated(const QString&);
-    void on_changePlot_activated(const QString&);
-    void on_spinTransparency_valueChanged(int);
-    void on_spinPointSize_valueChanged(int);
-    void on_spinLineWidth_valueChanged(int);
+    void setupConnections();
+    void onChangeModeActivated(const QString&);
+    void onChangePlotActivated(const QString&);
+    void onTransparencyValueChanged(int);
+    void onPointSizeValueChanged(int);
+    void onLineWidthValueChanged(int);
 
 protected:
     void changeEvent(QEvent *e) override;
diff --git a/src/Gui/TaskView/TaskSelectLinkProperty.cpp b/src/Gui/TaskView/TaskSelectLinkProperty.cpp
index 53e20ac55f..20627d4f2d 100644
--- a/src/Gui/TaskView/TaskSelectLinkProperty.cpp
+++ b/src/Gui/TaskView/TaskSelectLinkProperty.cpp
@@ -44,8 +44,7 @@ TaskSelectLinkProperty::TaskSelectLinkProperty(const char *sFilter,App::Property
     proxy = new QWidget(this);
     ui = new Ui_TaskSelectLinkProperty();
     ui->setupUi(proxy);
-
-    QMetaObject::connectSlotsByName(this);
+    setupConnections();
 
     this->groupLayout()->addWidget(proxy);
     Gui::Selection().Attach(this);
@@ -84,6 +83,18 @@ TaskSelectLinkProperty::~TaskSelectLinkProperty()
     Gui::Selection().Detach(this);
 }
 
+void TaskSelectLinkProperty::setupConnections()
+{
+    connect(ui->Remove, &QToolButton::clicked,
+            this, &TaskSelectLinkProperty::onRemoveClicked);
+    connect(ui->Add, &QToolButton::clicked,
+            this, &TaskSelectLinkProperty::onAddClicked);
+    connect(ui->Invert, &QToolButton::clicked,
+            this, &TaskSelectLinkProperty::onInvertClicked);
+    connect(ui->Help, &QToolButton::clicked,
+            this, &TaskSelectLinkProperty::onHelpClicked);
+}
+
 void TaskSelectLinkProperty::changeEvent(QEvent *e)
 {
     TaskBox::changeEvent(e);
@@ -222,19 +233,19 @@ void TaskSelectLinkProperty::OnChange(Gui::SelectionSingleton::SubjectType &rCal
 }
 /// @endcond
 
-void TaskSelectLinkProperty::on_Remove_clicked(bool)
+void TaskSelectLinkProperty::onRemoveClicked(bool)
 {
 }
 
-void TaskSelectLinkProperty::on_Add_clicked(bool)
+void TaskSelectLinkProperty::onAddClicked(bool)
 {
 }
 
-void TaskSelectLinkProperty::on_Invert_clicked(bool)
+void TaskSelectLinkProperty::onInvertClicked(bool)
 {
 }
 
-void TaskSelectLinkProperty::on_Help_clicked(bool)
+void TaskSelectLinkProperty::onHelpClicked(bool)
 {
 }
 
diff --git a/src/Gui/TaskView/TaskSelectLinkProperty.h b/src/Gui/TaskView/TaskSelectLinkProperty.h
index 497b30c661..099179d229 100644
--- a/src/Gui/TaskView/TaskSelectLinkProperty.h
+++ b/src/Gui/TaskView/TaskSelectLinkProperty.h
@@ -77,11 +77,12 @@ public:
     /// checks if the filter is currently met
     inline bool isSelectionValid() const {return Filter->match();}
 
-private Q_SLOTS:
-    void on_Remove_clicked(bool);
-    void on_Add_clicked(bool);
-    void on_Invert_clicked(bool);
-    void on_Help_clicked(bool);
+private:
+    void setupConnections();
+    void onRemoveClicked(bool);
+    void onAddClicked(bool);
+    void onInvertClicked(bool);
+    void onHelpClicked(bool);
 
 Q_SIGNALS:
     void emitSelectionFit();
diff --git a/src/Gui/TextureMapping.cpp b/src/Gui/TextureMapping.cpp
index 585fd5aeb6..ef026f0f11 100644
--- a/src/Gui/TextureMapping.cpp
+++ b/src/Gui/TextureMapping.cpp
@@ -51,6 +51,11 @@ TextureMapping::TextureMapping(QWidget* parent, Qt::WindowFlags fl)
 {
     ui = new Ui_TextureMapping();
     ui->setupUi(this);
+    connect(ui->fileChooser, &FileChooser::fileNameSelected,
+            this, &TextureMapping::onFileChooserFileNameSelected);
+    connect(ui->checkEnv, &QCheckBox::toggled,
+            this, &TextureMapping::onCheckEnvToggled);
+
     ui->checkGlobal->hide();
 
     // set a dummy string which is not a valid file name
@@ -74,7 +79,7 @@ TextureMapping::TextureMapping(QWidget* parent, Qt::WindowFlags fl)
     if (!path.empty()) {
         QString file = QString::fromUtf8(path.c_str());
         ui->fileChooser->setFileName(file);
-        on_fileChooser_fileNameSelected(file);
+        onFileChooserFileNameSelected(file);
     }
 }
 
@@ -119,7 +124,7 @@ void TextureMapping::keyPressEvent(QKeyEvent *e)
     e->ignore();
 }
 
-void TextureMapping::on_fileChooser_fileNameSelected(const QString& s)
+void TextureMapping::onFileChooserFileNameSelected(const QString& s)
 {
     QImage image;
     if (!image.load(s)) {
@@ -161,7 +166,7 @@ void TextureMapping::on_fileChooser_fileNameSelected(const QString& s)
     App::GetApplication().Config()["TextureImage"] = (const char*)s.toUtf8();
 }
 
-void TextureMapping::on_checkEnv_toggled(bool b)
+void TextureMapping::onCheckEnvToggled(bool b)
 {
     if (!this->grp)
         return;
diff --git a/src/Gui/TextureMapping.h b/src/Gui/TextureMapping.h
index a3ec51ac9c..d58dd9311c 100644
--- a/src/Gui/TextureMapping.h
+++ b/src/Gui/TextureMapping.h
@@ -44,9 +44,9 @@ public:
     void accept();
     void reject();
 
-private Q_SLOTS:
-    void on_fileChooser_fileNameSelected(const QString&);
-    void on_checkEnv_toggled(bool);
+private:
+    void onFileChooserFileNameSelected(const QString&);
+    void onCheckEnvToggled(bool);
 
 protected:
     void changeEvent(QEvent *e);
diff --git a/src/Gui/Transform.cpp b/src/Gui/Transform.cpp
index f79bdf71b4..f103195ff8 100644
--- a/src/Gui/Transform.cpp
+++ b/src/Gui/Transform.cpp
@@ -285,6 +285,9 @@ Transform::Transform(QWidget* parent, Qt::WindowFlags fl)
 {
     ui = new Ui_Placement();
     ui->setupUi(this);
+    connect(ui->applyButton, &QPushButton::clicked,
+            this, &Transform::onApplyButtonClicked);
+
     ui->resetButton->hide();
     ui->applyIncrementalPlacement->hide();
 
@@ -348,7 +351,7 @@ void Transform::onTransformChanged(int)
 
 void Transform::accept()
 {
-    on_applyButton_clicked();
+    onApplyButtonClicked();
     QDialog::accept();
 }
 
@@ -358,7 +361,7 @@ void Transform::reject()
     QDialog::reject();
 }
 
-void Transform::on_applyButton_clicked()
+void Transform::onApplyButtonClicked()
 {
     Gui::WaitCursor wc;
     Base::Placement plm = this->getPlacementData();
@@ -461,7 +464,7 @@ bool TaskTransform::reject()
 void TaskTransform::clicked(int id)
 {
     if (id == QDialogButtonBox::Apply) {
-        dialog->on_applyButton_clicked();
+        dialog->onApplyButtonClicked();
     }
 }
 
diff --git a/src/Gui/Transform.h b/src/Gui/Transform.h
index 1268bea0b7..9d52dd2a74 100644
--- a/src/Gui/Transform.h
+++ b/src/Gui/Transform.h
@@ -84,13 +84,11 @@ protected:
     Base::Vector3d getDirection() const;
     void changeEvent(QEvent *e) override;
 
-public Q_SLOTS:
-    void on_applyButton_clicked();
-
-private Q_SLOTS:
-    void onTransformChanged(int);
+public:
+    void onApplyButtonClicked();
 
 private:
+    void onTransformChanged(int);
     Base::Placement getPlacementData() const;
 
 private: