diff --git a/src/Gui/CommandFeat.cpp b/src/Gui/CommandFeat.cpp
index dfee930f48..730b77394e 100644
--- a/src/Gui/CommandFeat.cpp
+++ b/src/Gui/CommandFeat.cpp
@@ -25,8 +25,9 @@
 #ifndef _PreComp_
 #endif
 
-#include <App/DocumentObject.h>
+#include <App/DocumentObjectGroup.h>
 #include <App/GroupExtension.h>
+#include <App/Part.h>
 #include "Application.h"
 #include "CommandT.h"
 #include "DockWindowManager.h"
@@ -116,6 +117,10 @@ void StdCmdRandomColor::activated(int iMsg)
         }
     };
 
+    auto allowToChangeColor = [](const App::DocumentObject* obj) {
+        return (obj->isDerivedFrom<App::Part>() || obj->isDerivedFrom<App::DocumentObjectGroup>());
+    };
+
     // get the complete selection
     std::vector<SelectionSingleton::SelObj> sel = Selection().getCompleteSelection();
 
@@ -125,10 +130,12 @@ void StdCmdRandomColor::activated(int iMsg)
         setRandomColor(view);
 
         if (auto grp = it.pObject->getExtension<App::GroupExtension>()) {
-            std::vector<App::DocumentObject*> objs = grp->getObjects();
-            for (auto obj : objs) {
-                ViewProvider* view = Application::Instance->getViewProvider(obj);
-                setRandomColor(view);
+            if (allowToChangeColor(it.pObject)) {
+                std::vector<App::DocumentObject*> objs = grp->getObjects();
+                for (auto obj : objs) {
+                    ViewProvider* view = Application::Instance->getViewProvider(obj);
+                    setRandomColor(view);
+                }
             }
         }
     }
diff --git a/src/Gui/Quarter/QuarterWidgetP.cpp b/src/Gui/Quarter/QuarterWidgetP.cpp
index 5f3267e5c8..7771c4b79b 100644
--- a/src/Gui/Quarter/QuarterWidgetP.cpp
+++ b/src/Gui/Quarter/QuarterWidgetP.cpp
@@ -169,13 +169,22 @@ QuarterWidgetP::removeFromCacheContext(QuarterWidgetP_cachecontext * context, co
 
     for (int i = 0; i < cachecontext_list->getLength(); i++) {
       if ((*cachecontext_list)[i] == context) {
-        // set the context while calling destructingContext() (might trigger OpenGL calls)
-        const_cast<QtGLWidget*> (widget)->makeCurrent();
-        // fetch the cc_glglue context instance as a workaround for a bug fixed in Coin r12818
-        (void) cc_glglue_instance(context->id);
+        QtGLContext* glcontext = widget->context();
+        if (glcontext) {
+          // set the context while calling destructingContext() (might trigger OpenGL calls)
+          if (glcontext->isValid()) {
+            const_cast<QtGLWidget*> (widget)->makeCurrent();
+          }
+          // fetch the cc_glglue context instance as a workaround for a bug fixed in Coin r12818
+          (void) cc_glglue_instance(context->id);
+        }
         cachecontext_list->removeFast(i);
         SoContextHandler::destructingContext(context->id);
-        const_cast<QtGLWidget*> (widget)->doneCurrent();
+        if (glcontext) {
+          if (glcontext->isValid()) {
+            const_cast<QtGLWidget*> (widget)->doneCurrent();
+          }
+        }
         delete context;
         return;
       }
diff --git a/src/Gui/TaskView/TaskImage.cpp b/src/Gui/TaskView/TaskImage.cpp
index 0480fd8aa1..1e2cbaf509 100644
--- a/src/Gui/TaskView/TaskImage.cpp
+++ b/src/Gui/TaskView/TaskImage.cpp
@@ -204,16 +204,20 @@ void TaskImage::scaleImage(double factor)
 
 void TaskImage::startScale()
 {
-    scale->activate();
-    ui->pushButtonScale->hide();
-    ui->groupBoxCalibration->show();
-    ui->pushButtonApply->setEnabled(false);
+    if (scale) {
+        scale->activate();
+        ui->pushButtonScale->hide();
+        ui->groupBoxCalibration->show();
+        ui->pushButtonApply->setEnabled(false);
+    }
 }
 
 void TaskImage::acceptScale()
 {
-    scaleImage(scale->getScaleFactor());
-    rejectScale();
+    if (scale) {
+        scaleImage(scale->getScaleFactor());
+        rejectScale();
+    }
 }
 
 void TaskImage::enableApplyBtn()
@@ -223,9 +227,11 @@ void TaskImage::enableApplyBtn()
 
 void TaskImage::rejectScale()
 {
-    scale->deactivate();
-    ui->pushButtonScale->show();
-    ui->groupBoxCalibration->hide();
+    if (scale) {
+        scale->deactivate();
+        ui->pushButtonScale->show();
+        ui->groupBoxCalibration->hide();
+    }
 }
 
 void TaskImage::onInteractiveScale()
diff --git a/src/Gui/Workbench.cpp b/src/Gui/Workbench.cpp
index e4ca175b20..11fbdc2a5a 100644
--- a/src/Gui/Workbench.cpp
+++ b/src/Gui/Workbench.cpp
@@ -853,15 +853,13 @@ ToolBarItem* StdWorkbench::setupCommandBars() const
 DockWindowItems* StdWorkbench::setupDockWindows() const
 {
     auto root = new DockWindowItems();
-    root->addDockWidget("Std_ToolBox", Qt::RightDockWidgetArea, false, false);
-    //root->addDockWidget("Std_HelpView", Qt::RightDockWidgetArea, true, false);
     root->addDockWidget("Std_TreeView", Qt::LeftDockWidgetArea, true, false);
     root->addDockWidget("Std_PropertyView", Qt::LeftDockWidgetArea, true, false);
     root->addDockWidget("Std_SelectionView", Qt::LeftDockWidgetArea, false, false);
     root->addDockWidget("Std_ComboView", Qt::LeftDockWidgetArea, true, true);
     root->addDockWidget("Std_TaskView", Qt::LeftDockWidgetArea, true, true);
-    root->addDockWidget("Std_ReportView", Qt::BottomDockWidgetArea, true, true);
-    root->addDockWidget("Std_PythonView", Qt::BottomDockWidgetArea, true, true);
+    root->addDockWidget("Std_ReportView", Qt::BottomDockWidgetArea, false, true);
+    root->addDockWidget("Std_PythonView", Qt::BottomDockWidgetArea, false, true);
 
     //Dagview through parameter.
     ParameterGrp::handle group = App::GetApplication().GetUserParameter().
diff --git a/src/Mod/Mesh/Gui/Command.cpp b/src/Mod/Mesh/Gui/Command.cpp
index c086afbf9b..19d9360d72 100644
--- a/src/Mod/Mesh/Gui/Command.cpp
+++ b/src/Mod/Mesh/Gui/Command.cpp
@@ -904,8 +904,10 @@ CmdMeshTrimByPlane::CmdMeshTrimByPlane()
 
 void CmdMeshTrimByPlane::activated(int)
 {
-    doCommand(Doc,
-              "import MeshPartGui, FreeCADGui\nFreeCADGui.runCommand('MeshPart_TrimByPlane')\n");
+    const char* cmd = "import MeshPartGui\n"
+                      "import FreeCADGui\n"
+                      "FreeCADGui.runCommand('MeshPart_TrimByPlane')\n";
+    runCommand(Doc, cmd);
 }
 
 bool CmdMeshTrimByPlane::isActive()
@@ -935,8 +937,10 @@ CmdMeshSectionByPlane::CmdMeshSectionByPlane()
 
 void CmdMeshSectionByPlane::activated(int)
 {
-    doCommand(Doc,
-              "import MeshPartGui, FreeCADGui\nFreeCADGui.runCommand('MeshPart_SectionByPlane')\n");
+    const char* cmd = "import MeshPartGui\n"
+                      "import FreeCADGui\n"
+                      "FreeCADGui.runCommand('MeshPart_SectionByPlane')\n";
+    runCommand(Doc, cmd);
 }
 
 bool CmdMeshSectionByPlane::isActive()
@@ -966,8 +970,10 @@ CmdMeshCrossSections::CmdMeshCrossSections()
 
 void CmdMeshCrossSections::activated(int)
 {
-    doCommand(Doc,
-              "import MeshPartGui, FreeCADGui\nFreeCADGui.runCommand('MeshPart_CrossSections')\n");
+    const char* cmd = "import MeshPartGui\n"
+                      "import FreeCADGui\n"
+                      "FreeCADGui.runCommand('MeshPart_CrossSections')\n";
+    runCommand(Doc, cmd);
 }
 
 bool CmdMeshCrossSections::isActive()
diff --git a/src/Mod/MeshPart/Gui/Command.cpp b/src/Mod/MeshPart/Gui/Command.cpp
index 9e3b6cb0c5..1934ad5b25 100644
--- a/src/Mod/MeshPart/Gui/Command.cpp
+++ b/src/Mod/MeshPart/Gui/Command.cpp
@@ -230,7 +230,8 @@ void CmdMeshPartSection::activated(int)
     for (auto it : docObj) {
         const Mesh::MeshObject* mesh = static_cast<Mesh::Feature*>(it)->Mesh.getValuePtr();
         std::vector<Mesh::MeshObject::TPolylines> polylines;
-        mesh->crossSections(sections, polylines);
+        const float minSectionLength = 1e-7F;
+        mesh->crossSections(sections, polylines, minSectionLength);
 
         for (const auto& it2 : polylines) {
             for (const auto& it3 : it2) {
diff --git a/src/Mod/PartDesign/Gui/TaskThicknessParameters.cpp b/src/Mod/PartDesign/Gui/TaskThicknessParameters.cpp
index 5edc2a807a..05624eb89e 100644
--- a/src/Mod/PartDesign/Gui/TaskThicknessParameters.cpp
+++ b/src/Mod/PartDesign/Gui/TaskThicknessParameters.cpp
@@ -24,9 +24,9 @@
 #include "PreCompiled.h"
 
 #ifndef _PreComp_
-# include <QAction>
-# include <QListWidget>
-# include <QMessageBox>
+#include <QAction>
+#include <QListWidget>
+#include <QMessageBox>
 #endif
 
 #include <Base/Interpreter.h>
@@ -45,20 +45,28 @@ using namespace Gui;
 
 /* TRANSLATOR PartDesignGui::TaskThicknessParameters */
 
-TaskThicknessParameters::TaskThicknessParameters(ViewProviderDressUp *DressUpView, QWidget *parent)
+TaskThicknessParameters::TaskThicknessParameters(ViewProviderDressUp* DressUpView, QWidget* parent)
     : TaskDressUpParameters(DressUpView, false, true, parent)
     , ui(new Ui_TaskThicknessParameters)
+{
+    addContainerWidget();
+    initControls();
+}
+
+void TaskThicknessParameters::addContainerWidget()
 {
     // we need a separate container widget to add all controls to
     proxy = new QWidget(this);
     ui->setupUi(proxy);
     this->groupLayout()->addWidget(proxy);
+}
 
-    PartDesign::Thickness* pcThickness = static_cast<PartDesign::Thickness*>(DressUpView->getObject());
+void TaskThicknessParameters::initControls()
+{
+    auto pcThickness = dynamic_cast<PartDesign::Thickness*>(DressUpView->getObject());
     double a = pcThickness->Value.getValue();
 
     ui->Value->setMinimum(0.0);
-    ui->Value->setMaximum(89.99);
     ui->Value->setValue(a);
     ui->Value->selectAll();
     QMetaObject::invokeMethod(ui->Value, "setFocus", Qt::QueuedConnection);
@@ -73,54 +81,59 @@ TaskThicknessParameters::TaskThicknessParameters(ViewProviderDressUp *DressUpVie
     ui->checkIntersection->setChecked(i);
 
     std::vector<std::string> strings = pcThickness->Base.getSubValues();
-    for (const auto & string : strings)
-    {
+    for (const auto& string : strings) {
         ui->listWidgetReferences->addItem(QString::fromStdString(string));
     }
 
+    setupConnections();
+
+    int mode = static_cast<int>(pcThickness->Mode.getValue());
+    ui->modeComboBox->setCurrentIndex(mode);
+
+    int join = static_cast<int>(pcThickness->Join.getValue());
+    ui->joinComboBox->setCurrentIndex(join);
+
+    if (strings.empty()) {
+        setSelectionMode(refSel);
+    }
+    else {
+        hideOnError();
+    }
+}
+
+void TaskThicknessParameters::setupConnections()
+{
+    // clang-format off
     QMetaObject::connectSlotsByName(this);
 
     connect(ui->Value, qOverload<double>(&Gui::QuantitySpinBox::valueChanged),
-        this, &TaskThicknessParameters::onValueChanged);
+            this, &TaskThicknessParameters::onValueChanged);
     connect(ui->checkReverse, &QCheckBox::toggled,
-        this, &TaskThicknessParameters::onReversedChanged);
+            this, &TaskThicknessParameters::onReversedChanged);
     connect(ui->checkIntersection, &QCheckBox::toggled,
-        this, &TaskThicknessParameters::onIntersectionChanged);
+            this, &TaskThicknessParameters::onIntersectionChanged);
     connect(ui->buttonRefSel, &QToolButton::toggled,
-        this, &TaskThicknessParameters::onButtonRefSel);
+            this, &TaskThicknessParameters::onButtonRefSel);
     connect(ui->modeComboBox, qOverload<int>(&QComboBox::currentIndexChanged),
-        this, &TaskThicknessParameters::onModeChanged);
+            this, &TaskThicknessParameters::onModeChanged);
     connect(ui->joinComboBox, qOverload<int>(&QComboBox::currentIndexChanged),
-        this, &TaskThicknessParameters::onJoinTypeChanged);
+            this, &TaskThicknessParameters::onJoinTypeChanged);
 
     // Create context menu
     createDeleteAction(ui->listWidgetReferences);
     connect(deleteAction, &QAction::triggered, this, &TaskThicknessParameters::onRefDeleted);
 
     connect(ui->listWidgetReferences, &QListWidget::currentItemChanged,
-        this, &TaskThicknessParameters::setSelection);
+            this, &TaskThicknessParameters::setSelection);
     connect(ui->listWidgetReferences, &QListWidget::itemClicked,
-        this, &TaskThicknessParameters::setSelection);
+            this, &TaskThicknessParameters::setSelection);
     connect(ui->listWidgetReferences, &QListWidget::itemDoubleClicked,
-        this, &TaskThicknessParameters::doubleClicked);
-
-    int mode = pcThickness->Mode.getValue();
-    ui->modeComboBox->setCurrentIndex(mode);
-
-    int join = pcThickness->Join.getValue();
-    ui->joinComboBox->setCurrentIndex(join);
-
-    if (strings.size() == 0)
-        setSelectionMode(refSel);
-    else
-        hideOnError();
+            this, &TaskThicknessParameters::doubleClicked);
+    // clang-format on
 }
 
 void TaskThicknessParameters::onSelectionChanged(const Gui::SelectionChanges& msg)
 {
-    // executed when the user selected something in the CAD object
-    // adds/deletes the selection accordingly
-
     if (msg.Type == Gui::SelectionChanges::AddSelection) {
         if (selectionMode == refSel) {
             referenceSelected(msg, ui->listWidgetReferences);
@@ -139,37 +152,41 @@ void TaskThicknessParameters::onRefDeleted()
     TaskDressUpParameters::deleteRef(ui->listWidgetReferences);
 }
 
-void TaskThicknessParameters::onValueChanged(double angle)
+PartDesign::Thickness* TaskThicknessParameters::onBeforeChange()
 {
     setButtons(none);
-    PartDesign::Thickness* pcThickness = static_cast<PartDesign::Thickness*>(DressUpView->getObject());
     setupTransaction();
-    pcThickness->Value.setValue(angle);
-    pcThickness->getDocument()->recomputeFeature(pcThickness);
+    return dynamic_cast<PartDesign::Thickness*>(DressUpView->getObject());
+}
+
+void TaskThicknessParameters::onAfterChange(PartDesign::Thickness* obj)
+{
+    obj->recomputeFeature();
     // hide the thickness if there was a computation error
     hideOnError();
 }
 
-void TaskThicknessParameters::onJoinTypeChanged(int join) {
-
-    setButtons(none);
-    PartDesign::Thickness* pcThickness = static_cast<PartDesign::Thickness*>(DressUpView->getObject());
-    setupTransaction();
-    pcThickness->Join.setValue(join);
-    pcThickness->getDocument()->recomputeFeature(pcThickness);
-    // hide the thickness if there was a computation error
-    hideOnError();
+void TaskThicknessParameters::onValueChanged(double angle)
+{
+    PartDesign::Thickness* thickness = onBeforeChange();
+    thickness->Value.setValue(angle);
+    onAfterChange(thickness);
 }
 
-void TaskThicknessParameters::onModeChanged(int mode) {
+void TaskThicknessParameters::onJoinTypeChanged(int join)
+{
 
-    setButtons(none);
-    PartDesign::Thickness* pcThickness = static_cast<PartDesign::Thickness*>(DressUpView->getObject());
-    setupTransaction();
-    pcThickness->Mode.setValue(mode);
-    pcThickness->getDocument()->recomputeFeature(pcThickness);
-    // hide the thickness if there was a computation error
-    hideOnError();
+    PartDesign::Thickness* thickness = onBeforeChange();
+    thickness->Join.setValue(join);
+    onAfterChange(thickness);
+}
+
+void TaskThicknessParameters::onModeChanged(int mode)
+{
+
+    PartDesign::Thickness* thickness = onBeforeChange();
+    thickness->Mode.setValue(mode);
+    onAfterChange(thickness);
 }
 
 double TaskThicknessParameters::getValue() const
@@ -177,14 +194,11 @@ double TaskThicknessParameters::getValue() const
     return ui->Value->value().getValue();
 }
 
-void TaskThicknessParameters::onReversedChanged(const bool on) {
-    setButtons(none);
-    PartDesign::Thickness* pcThickness = static_cast<PartDesign::Thickness*>(DressUpView->getObject());
-    setupTransaction();
-    pcThickness->Reversed.setValue(on);
-    pcThickness->getDocument()->recomputeFeature(pcThickness);
-    // hide the thickness if there was a computation error
-    hideOnError();
+void TaskThicknessParameters::onReversedChanged(bool on)
+{
+    PartDesign::Thickness* thickness = onBeforeChange();
+    thickness->Reversed.setValue(on);
+    onAfterChange(thickness);
 }
 
 bool TaskThicknessParameters::getReversed() const
@@ -192,13 +206,11 @@ bool TaskThicknessParameters::getReversed() const
     return ui->checkReverse->isChecked();
 }
 
-void TaskThicknessParameters::onIntersectionChanged(const bool on) {
-    setButtons(none);
-    PartDesign::Thickness* pcThickness = static_cast<PartDesign::Thickness*>(DressUpView->getObject());
-    pcThickness->Intersection.setValue(on);
-    pcThickness->getDocument()->recomputeFeature(pcThickness);
-    // hide the thickness if there was a computation error
-    hideOnError();
+void TaskThicknessParameters::onIntersectionChanged(bool on)
+{
+    PartDesign::Thickness* thickness = onBeforeChange();
+    thickness->Intersection.setValue(on);
+    onAfterChange(thickness);
 }
 
 bool TaskThicknessParameters::getIntersection() const
@@ -206,12 +218,14 @@ bool TaskThicknessParameters::getIntersection() const
     return ui->checkIntersection->isChecked();
 }
 
-int TaskThicknessParameters::getJoinType() const {
+int TaskThicknessParameters::getJoinType() const
+{
 
     return ui->joinComboBox->currentIndex();
 }
 
-int TaskThicknessParameters::getMode() const {
+int TaskThicknessParameters::getMode() const
+{
 
     return ui->modeComboBox->currentIndex();
 }
@@ -223,17 +237,17 @@ TaskThicknessParameters::~TaskThicknessParameters()
         Gui::Selection().rmvSelectionGate();
     }
     catch (const Py::Exception&) {
-        Base::PyException e; // extract the Python error text
+        Base::PyException e;  // extract the Python error text
         e.ReportException();
     }
 }
 
-bool TaskThicknessParameters::event(QEvent *e)
+bool TaskThicknessParameters::event(QEvent* e)
 {
     return TaskDressUpParameters::KeyEvent(e);
 }
 
-void TaskThicknessParameters::changeEvent(QEvent *e)
+void TaskThicknessParameters::changeEvent(QEvent* e)
 {
     TaskBox::changeEvent(e);
     if (e->type() == QEvent::LanguageChange) {
@@ -243,9 +257,10 @@ void TaskThicknessParameters::changeEvent(QEvent *e)
 
 void TaskThicknessParameters::apply()
 {
-    //Alert user if he created an empty feature
-    if (ui->listWidgetReferences->count() == 0)
+    // Alert user if he created an empty feature
+    if (ui->listWidgetReferences->count() == 0) {
         Base::Console().Warning(tr("Empty thickness created !\n").toStdString().c_str());
+    }
 }
 
 //**************************************************************************
@@ -253,48 +268,32 @@ void TaskThicknessParameters::apply()
 // TaskDialog
 //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
-TaskDlgThicknessParameters::TaskDlgThicknessParameters(ViewProviderThickness *DressUpView)
+TaskDlgThicknessParameters::TaskDlgThicknessParameters(ViewProviderThickness* DressUpView)
     : TaskDlgDressUpParameters(DressUpView)
 {
-    parameter  = new TaskThicknessParameters(DressUpView);
+    parameter = new TaskThicknessParameters(DressUpView);
 
     Content.push_back(parameter);
 }
 
 TaskDlgThicknessParameters::~TaskDlgThicknessParameters() = default;
 
-//==== calls from the TaskView ===============================================================
-
-
-//void TaskDlgThicknessParameters::open()
-//{
-//    // a transaction is already open at creation time of the draft
-//    if (!Gui::Command::hasPendingCommand()) {
-//        QString msg = QObject::tr("Edit draft");
-//        Gui::Command::openCommand((const char*)msg.toUtf8());
-//    }
-//}
-//
-//void TaskDlgThicknessParameters::clicked(int)
-//{
-//
-//}
-
 bool TaskDlgThicknessParameters::accept()
 {
     auto obj = vp->getObject();
-    if (!obj->isError())
+    if (!obj->isError()) {
         parameter->showObject();
+    }
 
     parameter->apply();
 
-    TaskThicknessParameters* draftparameter = static_cast<TaskThicknessParameters*>(parameter);
+    auto draftparameter = dynamic_cast<TaskThicknessParameters*>(parameter);
 
-    FCMD_OBJ_CMD(obj,"Value = " << draftparameter->getValue());
-    FCMD_OBJ_CMD(obj,"Reversed = " << draftparameter->getReversed());
-    FCMD_OBJ_CMD(obj,"Mode = " << draftparameter->getMode());
-    FCMD_OBJ_CMD(obj,"Intersection = " << draftparameter->getIntersection());
-    FCMD_OBJ_CMD(obj,"Join = " << draftparameter->getJoinType());
+    FCMD_OBJ_CMD(obj, "Value = " << draftparameter->getValue());
+    FCMD_OBJ_CMD(obj, "Reversed = " << draftparameter->getReversed());
+    FCMD_OBJ_CMD(obj, "Mode = " << draftparameter->getMode());
+    FCMD_OBJ_CMD(obj, "Intersection = " << draftparameter->getIntersection());
+    FCMD_OBJ_CMD(obj, "Join = " << draftparameter->getJoinType());
 
     return TaskDlgDressUpParameters::accept();
 }
diff --git a/src/Mod/PartDesign/Gui/TaskThicknessParameters.h b/src/Mod/PartDesign/Gui/TaskThicknessParameters.h
index 7d16706a98..35c2194044 100644
--- a/src/Mod/PartDesign/Gui/TaskThicknessParameters.h
+++ b/src/Mod/PartDesign/Gui/TaskThicknessParameters.h
@@ -29,14 +29,20 @@
 
 class Ui_TaskThicknessParameters;
 
-namespace PartDesignGui {
+namespace PartDesign
+{
+class Thickness;
+}
 
-class TaskThicknessParameters : public TaskDressUpParameters
+namespace PartDesignGui
+{
+
+class TaskThicknessParameters: public TaskDressUpParameters
 {
     Q_OBJECT
 
 public:
-    explicit TaskThicknessParameters(ViewProviderDressUp *DressUpView, QWidget *parent=nullptr);
+    explicit TaskThicknessParameters(ViewProviderDressUp* DressUpView, QWidget* parent = nullptr);
     ~TaskThicknessParameters() override;
 
     void apply() override;
@@ -44,34 +50,41 @@ public:
     double getValue() const;
     bool getReversed() const;
     bool getIntersection() const;
-    int  getMode() const;
-    int  getJoinType() const;
+    int getMode() const;
+    int getJoinType() const;
 
 private Q_SLOTS:
     void onValueChanged(double angle);
     void onModeChanged(int mode);
     void onJoinTypeChanged(int join);
-    void onReversedChanged(bool reversed);
-    void onIntersectionChanged(bool intersection);
+    void onReversedChanged(bool on);
+    void onIntersectionChanged(bool on);
     void onRefDeleted() override;
 
 protected:
     void setButtons(const selectionModes mode) override;
-    bool event(QEvent *e) override;
-    void changeEvent(QEvent *e) override;
+    bool event(QEvent* e) override;
+    void changeEvent(QEvent* e) override;
     void onSelectionChanged(const Gui::SelectionChanges& msg) override;
 
+private:
+    void addContainerWidget();
+    void initControls();
+    void setupConnections();
+    PartDesign::Thickness* onBeforeChange();
+    void onAfterChange(PartDesign::Thickness* obj);
+
 private:
     std::unique_ptr<Ui_TaskThicknessParameters> ui;
 };
 
 /// simulation dialog for the TaskView
-class TaskDlgThicknessParameters : public TaskDlgDressUpParameters
+class TaskDlgThicknessParameters: public TaskDlgDressUpParameters
 {
     Q_OBJECT
 
 public:
-    explicit TaskDlgThicknessParameters(ViewProviderThickness *ThicknessView);
+    explicit TaskDlgThicknessParameters(ViewProviderThickness* ThicknessView);
     ~TaskDlgThicknessParameters() override;
 
 public:
@@ -79,6 +92,6 @@ public:
     bool accept() override;
 };
 
-} //namespace PartDesignGui
+}  // namespace PartDesignGui
 
-#endif // GUI_TASKVIEW_TASKAPPERANCE_H
+#endif  // GUI_TASKVIEW_TASKAPPERANCE_H
diff --git a/src/Mod/PartDesign/Gui/ViewProviderBody.cpp b/src/Mod/PartDesign/Gui/ViewProviderBody.cpp
index aa78a19e97..79947520cf 100644
--- a/src/Mod/PartDesign/Gui/ViewProviderBody.cpp
+++ b/src/Mod/PartDesign/Gui/ViewProviderBody.cpp
@@ -427,7 +427,6 @@ void ViewProviderBody::unifyVisualProperty(const App::Property* prop) {
     if (prop == &Visibility ||
         prop == &Selectable ||
         prop == &DisplayModeBody ||
-        prop == &ShapeAppearance ||
         prop == &PointColorArray ||
         prop == &LineColorArray) {
         return;
diff --git a/src/Mod/PartDesign/Gui/Workbench.cpp b/src/Mod/PartDesign/Gui/Workbench.cpp
index 651c1fae1e..0c4b196d2e 100644
--- a/src/Mod/PartDesign/Gui/Workbench.cpp
+++ b/src/Mod/PartDesign/Gui/Workbench.cpp
@@ -68,111 +68,18 @@ namespace sp = std::placeholders;
 /// @namespace PartDesignGui @class Workbench
 TYPESYSTEM_SOURCE(PartDesignGui::Workbench, Gui::StdWorkbench)
 
-Workbench::Workbench() {
-}
+Workbench::Workbench() = default;
 
-Workbench::~Workbench() {
+Workbench::~Workbench()
+{
     WorkflowManager::destruct();
 }
 
-void Workbench::_switchToDocument(const App::Document* /*doc*/)
-{
-// TODO Commented out for thurther remove or rewrite  (2015-09-04, Fat-Zer)
-//    if (doc == NULL) return;
-//
-//    PartDesign::Body* activeBody = NULL;
-//    std::vector<App::DocumentObject*> bodies = doc->getObjectsOfType(PartDesign::Body::getClassTypeId());
-//
-//    // No tip, so build up structure or migrate
-//    if (!doc->Tip.getValue())
-//    {
-//        ;/*if (doc->countObjects() == 0){
-//            buildDefaultPartAndBody(doc);
-//            activeBody = Gui::Application::Instance->activeView()->getActiveObject<PartDesign::Body*>(PDBODYKEY);
-//            assert(activeBody);
-//        } else {
-//            // empty document with no tip, so do migration
-//            _doMigration(doc);
-//                        activeBody = Gui::Application::Instance->activeView()->getActiveObject<PartDesign::Body*>(PDBODYKEY);
-//                        assert(activeBody);
-//                }
-//                */
-//    }
-//    else
-//    {
-//      App::Part *docPart = dynamic_cast<App::Part *>(doc->Tip.getValue());
-//      if (docPart) {
-//          App::Part *viewPart = Gui::Application::Instance->activeView()->getActiveObject<App::Part *>("Part");
-//          if (viewPart != docPart)
-//            Gui::Application::Instance->activeView()->setActiveObject(docPart, "Part");
-//          //if (docPart->countObjectsOfType(PartDesign::Body::getClassTypeId()) < 1)
-//          //  setUpPart(docPart);
-//          PartDesign::Body *tempBody = dynamic_cast<PartDesign::Body *> (docPart->getObjectsOfType(PartDesign::Body::getClassTypeId()).front());
-//          if (tempBody) {
-//              PartDesign::Body *viewBody = Gui::Application::Instance->activeView()->getActiveObject<PartDesign::Body*>(PDBODYKEY);
-//              activeBody = viewBody;
-//              if (!viewBody)
-//                activeBody = tempBody;
-//              else if (!docPart->hasObject(viewBody))
-//                activeBody = tempBody;
-//
-//              if (activeBody != viewBody)
-//                Gui::Application::Instance->activeView()->setActiveObject(activeBody, PDBODYKEY);
-//          }
-//      }
-//    }
-//
-//    /*if (activeBody == NULL) {
-//        QMessageBox::critical(Gui::getMainWindow(), QObject::tr("Could not create body"),
-//            QObject::tr("No body was found in this document, and none could be created. Please report this bug."
-//                        "We recommend you do not use this document with the PartDesign workbench until the bug has been fixed."
-//                        ));
-//    }*/
-}
-
-void Workbench::slotActiveDocument(const Gui::Document& /*Doc*/)
-{
-//     _switchToDocument(Doc.getDocument());
-}
-
-void Workbench::slotNewDocument(const App::Document& /*Doc*/)
-{
-//     _switchToDocument(&Doc);
-}
-
-void Workbench::slotFinishRestoreDocument(const App::Document& /*Doc*/)
-{
-//     _switchToDocument(&Doc);
-}
-
-void Workbench::slotDeleteDocument(const App::Document&)
-{
-    //ActivePartObject = 0;
-    //ActiveGuiDoc = 0;
-    //ActiveAppDoc = 0;
-    //ActiveVp = 0;
-}
-/*
-  This does not work for Std_DuplicateSelection:
-  Tree.cpp gives: "Cannot reparent unknown object", probably because the signalNewObject is emitted
-  before the duplication of the object has been completely finished
-
-void Workbench::slotNewObject(const App::DocumentObject& obj)
-{
-    if ((obj.getDocument() == ActiveAppDoc) && (ActivePartObject != NULL)) {
-        // Add the new object to the active Body
-        // Note: Will this break Undo? But how else can we catch Edit->Duplicate selection?
-        Gui::Command::doCommand(Gui::Command::Doc,"App.activeDocument().%s.addObject(App.activeDocument().%s)",
-                                ActivePartObject->getNameInDocument(), obj.getNameInDocument());
-    }
-}
-*/
-
 void Workbench::setupContextMenu(const char* recipient, Gui::MenuItem* item) const
 {
     auto selection = Gui::Selection().getSelection();
     // Add move Tip Command
-    if ( !selection.empty() ) {
+    if (!selection.empty()) {
         App::DocumentObject *feature = selection.front().pObject;
         PartDesign::Body *body = nullptr;
 
@@ -434,7 +341,6 @@ void Workbench::activated()
         "PartDesign_Mirrored",
         "PartDesign_LinearPattern",
         "PartDesign_PolarPattern",
-//        "PartDesign_Scaled",
         "PartDesign_MultiTransform",
         nullptr};
     Watcher.push_back(new Gui::TaskView::TaskWatcherCommands(
@@ -444,37 +350,18 @@ void Workbench::activated()
         "PartDesign_MultiTransform"
     ));
 
-    // make the previously used active Body active again
-    //PartDesignGui::ActivePartObject = NULL;
-    _switchToDocument(App::GetApplication().getActiveDocument());
-
     addTaskWatcher(Watcher);
     if(App::GetApplication().GetUserParameter().GetGroup("BaseApp")->GetGroup("Preferences")->GetGroup("Mod/PartDesign")->GetBool("SwitchToTask", true))
         Gui::Control().showTaskView();
-
-    //NOLINTBEGIN
-    // Let us be notified when a document is activated, so that we can update the ActivePartObject
-    activeDoc = Gui::Application::Instance->signalActiveDocument.connect(std::bind(&Workbench::slotActiveDocument, this, sp::_1));
-    createDoc = App::GetApplication().signalNewDocument.connect(std::bind(&Workbench::slotNewDocument, this, sp::_1));
-    finishDoc = App::GetApplication().signalFinishRestoreDocument.connect(std::bind(&Workbench::slotFinishRestoreDocument, this, sp::_1));
-    deleteDoc = App::GetApplication().signalDeleteDocument.connect(std::bind(&Workbench::slotDeleteDocument, this, sp::_1));
-    //NOLINTEND
 }
 
 void Workbench::deactivated()
 {
-    // Let us be notified when a document is activated, so that we can update the ActivePartObject
-    activeDoc.disconnect();
-    createDoc.disconnect();
-    finishDoc.disconnect();
-    deleteDoc.disconnect();
-
     removeTaskWatcher();
     // reset the active Body
     Gui::Command::doCommand(Gui::Command::Doc,"import PartDesignGui");
 
     Gui::Workbench::deactivated();
-
 }
 
 Gui::MenuItem* Workbench::setupMenuBar() const
@@ -536,7 +423,6 @@ Gui::MenuItem* Workbench::setupMenuBar() const
                      << "PartDesign_LinearPattern"
                      << "PartDesign_PolarPattern"
                      << "PartDesign_MultiTransform";
-//                     << "PartDesign_Scaled"
 
     // dressups
     Gui::MenuItem* dressups = new Gui::MenuItem;
@@ -572,7 +458,6 @@ Gui::MenuItem* Workbench::setupMenuBar() const
           << "Separator"
           << "Part_CheckGeometry"
           << "Separator"
-          << "PartDesign_Migrate"
           << "PartDesign_Sprocket";
 
     // For 0.13 a couple of python packages like numpy, matplotlib and others
@@ -650,16 +535,7 @@ Gui::ToolBarItem* Workbench::setupToolBars() const
     *part << "PartDesign_Mirrored"
           << "PartDesign_LinearPattern"
           << "PartDesign_PolarPattern"
-          // << "PartDesign_Scaled"
           << "PartDesign_MultiTransform";
 
     return root;
 }
-
-Gui::ToolBarItem* Workbench::setupCommandBars() const
-{
-    // Part tools
-    Gui::ToolBarItem* root = new Gui::ToolBarItem;
-    return root;
-}
-
diff --git a/src/Mod/PartDesign/Gui/Workbench.h b/src/Mod/PartDesign/Gui/Workbench.h
index 5138f78e02..af2bf5137b 100644
--- a/src/Mod/PartDesign/Gui/Workbench.h
+++ b/src/Mod/PartDesign/Gui/Workbench.h
@@ -30,8 +30,6 @@
 namespace Gui {
 
 class MenuItem;
-class Document;
-class ViewProviderDocumentObject;
 
 }
 
@@ -48,7 +46,7 @@ public:
     Workbench();
     ~Workbench() override;
 
-      /** Run some actions when the workbench gets activated. */
+    /** Run some actions when the workbench gets activated. */
     void activated() override;
     /** Run some actions when the workbench gets deactivated. */
     void deactivated() override;
@@ -57,29 +55,8 @@ public:
     void setupContextMenu(const char* recipient, Gui::MenuItem*) const override;
 
 protected:
-  Gui::MenuItem* setupMenuBar() const override;
-  Gui::ToolBarItem* setupToolBars() const override;
-  Gui::ToolBarItem* setupCommandBars() const override;
-
-private:
-   /// Refresh the Body's highlighting when a document becomes active
-   void slotActiveDocument(const Gui::Document&);
-   /// Refresh the highlighting. Migrate legacy documents on loading
-   void slotFinishRestoreDocument(const App::Document&);
-   /// Ensure that there are base planes and a body in a new document
-   void slotNewDocument(const App::Document&);
-   /// Update the ActivePartObject etc. when a document is closed
-   void slotDeleteDocument(const App::Document&);
-   // Add new objects to the body, if appropriate
-   //void slotNewObject(const App::DocumentObject& obj);
-
-   void _switchToDocument(const App::Document* doc);
-
-private:
-   boost::signals2::connection activeDoc;
-   boost::signals2::connection createDoc;
-   boost::signals2::connection finishDoc;
-   boost::signals2::connection deleteDoc;
+    Gui::MenuItem* setupMenuBar() const override;
+    Gui::ToolBarItem* setupToolBars() const override;
 };
 
 } // namespace PartDesignGui
diff --git a/src/Mod/Sketcher/App/ExternalGeometryFacade.cpp b/src/Mod/Sketcher/App/ExternalGeometryFacade.cpp
index 6cc6efaac8..152e10bd2b 100644
--- a/src/Mod/Sketcher/App/ExternalGeometryFacade.cpp
+++ b/src/Mod/Sketcher/App/ExternalGeometryFacade.cpp
@@ -91,7 +91,7 @@ void ExternalGeometryFacade::initExtensions()
 
         getGeo()->setExtension(std::make_unique<SketchGeometryExtension>());  // Create getExtension
 
-        Base::Console().Warning("%s\nSketcher External Geometry without Geometry Extension: %s \n",
+        Base::Console().Warning("Sketcher External Geometry without Geometry Extension: %s \n",
                                 boost::uuids::to_string(Geo->getTag()).c_str());
     }
 
@@ -101,7 +101,7 @@ void ExternalGeometryFacade::initExtensions()
             std::make_unique<ExternalGeometryExtension>());  // Create getExtension
 
         Base::Console().Warning(
-            "%s\nSketcher External Geometry without ExternalGeometryExtension: %s \n",
+            "Sketcher External Geometry without ExternalGeometryExtension: %s \n",
             boost::uuids::to_string(Geo->getTag()).c_str());
     }
 
diff --git a/src/Mod/Spreadsheet/App/Sheet.cpp b/src/Mod/Spreadsheet/App/Sheet.cpp
index e730ca29f0..241bdf30e9 100644
--- a/src/Mod/Spreadsheet/App/Sheet.cpp
+++ b/src/Mod/Spreadsheet/App/Sheet.cpp
@@ -1785,7 +1785,7 @@ PROPERTY_SOURCE_TEMPLATE(Spreadsheet::SheetPython, Spreadsheet::Sheet)
 template<>
 const char* Spreadsheet::SheetPython::getViewProviderName() const
 {
-    return "SpreadsheetGui::ViewProviderSheet";
+    return "SpreadsheetGui::ViewProviderSheetPython";
 }
 template<>
 PyObject* Spreadsheet::SheetPython::getPyObject()
diff --git a/src/Mod/Start/Gui/Manipulator.cpp b/src/Mod/Start/Gui/Manipulator.cpp
index 1682bb9cda..03522ada4e 100644
--- a/src/Mod/Start/Gui/Manipulator.cpp
+++ b/src/Mod/Start/Gui/Manipulator.cpp
@@ -56,10 +56,9 @@ void CmdStart::activated(int iMsg)
 {
     Q_UNUSED(iMsg);
     auto mw = Gui::getMainWindow();
-    auto doc = Gui::Application::Instance->activeDocument();
     auto existingView = mw->findChild<StartGui::StartView*>(QLatin1String("StartView"));
     if (!existingView) {
-        existingView = gsl::owner<StartGui::StartView*>(new StartGui::StartView(doc, mw));
+        existingView = gsl::owner<StartGui::StartView*>(new StartGui::StartView(mw));
         mw->addWindow(existingView);  // Transfers ownership
     }
     Gui::getMainWindow()->setActiveWindow(existingView);
diff --git a/src/Mod/Start/Gui/StartView.cpp b/src/Mod/Start/Gui/StartView.cpp
index 432c469bea..5232c55ad3 100644
--- a/src/Mod/Start/Gui/StartView.cpp
+++ b/src/Mod/Start/Gui/StartView.cpp
@@ -100,8 +100,8 @@ gsl::owner<QPushButton*> createNewButton(const NewButton& newButton)
 
 }  // namespace
 
-StartView::StartView(Gui::Document* pcDocument, QWidget* parent)
-    : Gui::MDIView(pcDocument, parent)
+StartView::StartView(QWidget* parent)
+    : Gui::MDIView(nullptr, parent)
     , _contents(new QScrollArea(parent))
     , _newFileLabel {nullptr}
     , _examplesLabel {nullptr}
diff --git a/src/Mod/Start/Gui/StartView.h b/src/Mod/Start/Gui/StartView.h
index 33beea9980..fe2d33167c 100644
--- a/src/Mod/Start/Gui/StartView.h
+++ b/src/Mod/Start/Gui/StartView.h
@@ -54,7 +54,7 @@ class StartGuiExport StartView: public Gui::MDIView
     TYPESYSTEM_HEADER_WITH_OVERRIDE();  // NOLINT
 
 public:
-    StartView(Gui::Document* pcDocument, QWidget* parent);
+    StartView(QWidget* parent);
 
     const char* getName() const override
     {