Start: Recreate start as a QtWidgets-based app

Removes all Start network access and dependency on Chromium for rendering. Written
entirely in C++ (no HTML, CSS, JS, etc.).

.gitmodules

@@ -4,3 +4,6 @@
 [submodule "tests/lib"]
 	path = tests/lib
 	url = https://github.com/google/googletest
+[submodule "src/3rdParty/GSL"]
+	path = src/3rdParty/GSL
+	url = https://github.com/microsoft/GSL

cMake/FreeCAD_Helpers/PrintFinalReport.cmake

@@ -88,11 +88,39 @@ macro(PrintFinalReport)
     value(FREECAD_CREATE_MAC_APP)
     value(FREECAD_USE_PYBIND11)
     value(FREECAD_USE_EXTERNAL_KDL)
+    value(BUILD_ADDONMGR)
+    value(BUILD_ARCH)
+    value(BUILD_ASSEMBLY)
+    value(BUILD_CLOUD)
+    value(BUILD_DRAFT)
+    value(BUILD_DRAWING)
     value(BUILD_FEM)
-    value(BUILD_WEB)
-    value(BUILD_GUI)
+    value(BUILD_HELP)
+    value(BUILD_IDF)
+    value(BUILD_IMPORT)
+    value(BUILD_INSPECTION)
+    value(BUILD_JTREADER)
+    value(BUILD_MATERIAL)
+    value(BUILD_MESH)
+    value(BUILD_MESH_PART)
+    value(BUILD_OPENSCAD)
+    value(BUILD_PART)
+    value(BUILD_PART_DESIGN)
+    value(BUILD_PATH)
+    value(BUILD_PLOT)
+    value(BUILD_POINTS)
+    value(BUILD_REVERSEENGINEERING)
+    value(BUILD_ROBOT)
+    value(BUILD_SANDBOX)
+    value(BUILD_SHOW)
+    value(BUILD_SKETCHER)
+    value(BUILD_SPREADSHEET)
     value(BUILD_START)
+    value(BUILD_SURFACE)
     value(BUILD_TECHDRAW)
+    value(BUILD_TEST)
+    value(BUILD_TUX)
+    value(BUILD_WEB)
     value(CMAKE_INSTALL_PREFIX)
     value(USE_CUDA)
     value(USE_OPENCV)

src/Gui/Icons/resource.qrc

@@ -12,6 +12,7 @@
         <file>list-add.svg</file>
         <file>freecad.svg</file>
         <file>freecad-doc.png</file>
+        <file>freecad-doc.svg</file>
         <file>bulb.svg</file>
         <file>TextDocument.svg</file>
         <file>button_down.svg</file>

src/Mod/Assembly/Gui/Resources/Assembly.qrc

@@ -16,5 +16,6 @@
         <file>panels/TaskAssemblyInsertLink.ui</file>
         <file>preferences/Assembly.ui</file>
         <file>icons/Assembly_CreateJointDistance.svg</file>
+        <file>icons/AssemblyWorkbench.svg</file>
     </qresource>
 </RCC>

src/Mod/CMakeLists.txt

@@ -10,6 +10,10 @@ if(BUILD_ASSEMBLY)
   add_subdirectory(Assembly)
 endif(BUILD_ASSEMBLY)
 
+if(BUILD_CLEANSTART)
+    add_subdirectory(CleanStart)
+endif(BUILD_CLEANSTART)
+
 if(BUILD_CLOUD)
     add_subdirectory(Cloud)
 endif(BUILD_CLOUD)

src/Mod/CleanStart/App/AppCleanStart.cpp

@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+
+#include <Base/Interpreter.h>
+#include <Base/Tools.h>
+#include <Base/Console.h>
+
+#include <Base/PyObjectBase.h>
+
+#include <3rdParty/GSL/include/gsl/pointers>
+
+namespace CleanStart
+{
+class Module: public Py::ExtensionModule<Module>
+{
+public:
+    Module()
+        : Py::ExtensionModule<Module>("CleanStart")
+    {
+        initialize("This module is the CleanStart module.");  // register with Python
+    }
+};
+
+PyObject* initModule()
+{
+    auto newModule = gsl::owner<Module *>(new Module);
+    return Base::Interpreter().addModule(newModule);  // Transfer ownership
+}
+
+}  // namespace CleanStart
+
+/* Python entry */
+PyMOD_INIT_FUNC(CleanStart)
+{
+    PyObject* mod = CleanStart::initModule();
+    Base::Console().Log("Loading CleanStart module... done\n");
+    PyMOD_Return(mod);
+}

src/Mod/CleanStart/App/CMakeLists.txt

@@ -0,0 +1,50 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# /****************************************************************************
+#  *                                                                          *
+#  *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+#  *                                                                          *
+#  *   This file is part of FreeCAD.                                          *
+#  *                                                                          *
+#  *   FreeCAD is free software: you can redistribute it and/or modify it     *
+#  *   under the terms of the GNU Lesser General Public License as            *
+#  *   published by the Free Software Foundation, either version 2.1 of the   *
+#  *   License, or (at your option) any later version.                        *
+#  *                                                                          *
+#  *   FreeCAD 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       *
+#  *   Lesser General Public License for more details.                        *
+#  *                                                                          *
+#  *   You should have received a copy of the GNU Lesser General Public       *
+#  *   License along with FreeCAD. If not, see                                *
+#  *   <https://www.gnu.org/licenses/>.                                       *
+#  *                                                                          *
+#  ***************************************************************************/
+
+include_directories(
+        ${PYTHON_INCLUDE_DIRS}
+        ${QtCore_INCLUDE_DIRS}
+)
+
+set(CleanStart_LIBS
+        FreeCADApp
+        )
+
+SET(CleanStart_SRCS
+        AppCleanStart.cpp
+        DisplayedFilesModel.cpp
+        DisplayedFilesModel.h
+        ExamplesModel.cpp
+        ExamplesModel.h
+        PreCompiled.cpp
+        PreCompiled.h
+        RecentFilesModel.cpp
+        RecentFilesModel.h)
+
+add_library(CleanStart SHARED ${CleanStart_SRCS})
+target_link_libraries(CleanStart ${CleanStart_LIBS})
+
+SET_BIN_DIR(CleanStart CleanStart /Mod/CleanStart)
+SET_PYTHON_PREFIX_SUFFIX(CleanStart)
+
+INSTALL(TARGETS CleanStart DESTINATION ${CMAKE_INSTALL_LIBDIR})

src/Mod/CleanStart/App/DisplayedFilesModel.cpp

@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+#ifndef _PreComp_
+#include <QByteArray>
+#include <QFile>
+#include <QFileInfo>
+#endif
+
+#include "DisplayedFilesModel.h"
+#include <App/Application.h>
+#include <App/ProjectFile.h>
+
+using namespace CleanStart;
+
+
+namespace
+{
+
+std::string humanReadableSize(unsigned int bytes)
+{
+    static const std::vector<std::string> siPrefix {
+        "b",
+        "kb",
+        "Mb",
+        "Gb",
+        "Tb",
+        "Pb",
+        "Eb"  // I think it's safe to stop here (for the time being)...
+    };
+    size_t base = 0;
+    double inUnits = bytes;
+    constexpr double siFactor {1000.0};
+    while (inUnits > siFactor && base < siPrefix.size() - 1) {
+        ++base;
+        inUnits /= siFactor;
+    }
+    if (base == 0) {
+        // Don't include a decimal point for bytes
+        return fmt::format("{:.0f} {}", inUnits, siPrefix[base]);
+    }
+    // For all others, include one digit after the decimal place
+    return fmt::format("{:.1f} {}", inUnits, siPrefix[base]);
+}
+
+FileStats fileInfoFromFreeCADFile(const std::string& path)
+{
+    App::ProjectFile proj(path);
+    proj.loadDocument();
+    auto metadata = proj.getMetadata();
+    FileStats result;
+    result.insert(std::make_pair(DisplayedFilesModelRoles::author, metadata.createdBy));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::modifiedTime, metadata.lastModifiedDate));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::creationTime, metadata.creationDate));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::company, metadata.company));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::license, metadata.license));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::description, metadata.comment));
+    return result;
+}
+
+/// Load the thumbnail image data (if any) that is stored in an FCStd file.
+/// \returns The image bytes, or an empty QByteArray (if no thumbnail was stored)
+QByteArray loadFCStdThumbnail(const std::string & pathToFCStdFile)
+{
+    App::ProjectFile proj(pathToFCStdFile);
+    if (proj.loadDocument()) {
+        try {
+            std::string thumbnailFile = proj.extractInputFile("thumbnails/Thumbnail.png");
+            auto inputFile = QFile(QString::fromStdString(thumbnailFile));
+            inputFile.open(QIODevice::OpenModeFlag::ReadOnly);
+            return inputFile.readAll();
+        }
+        catch (...) {
+        }
+    }
+    return {};
+}
+
+FileStats getFileInfo(const std::string& path)
+{
+    FileStats result;
+    Base::FileInfo file(path);
+    if (file.hasExtension("FCStd")) {
+        result = fileInfoFromFreeCADFile(path);
+    }
+    else {
+        file.lastModified();
+    }
+    result.insert(std::make_pair(DisplayedFilesModelRoles::path, path));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::size, humanReadableSize(file.size())));
+    result.insert(std::make_pair(DisplayedFilesModelRoles::baseName, file.fileName()));
+    return result;
+}
+}  // namespace
+
+DisplayedFilesModel::DisplayedFilesModel(QObject* parent) : QAbstractListModel(parent)
+{
+}
+
+
+int DisplayedFilesModel::rowCount(const QModelIndex& parent) const
+{
+    Q_UNUSED(parent);
+    return static_cast<int>(_fileInfoCache.size());
+}
+
+QVariant DisplayedFilesModel::data(const QModelIndex& index, int roleAsInt) const
+{
+    int row = index.row();
+    if (row < 0 || row >= static_cast<int>(_fileInfoCache.size())) {
+        return {};
+    }
+    auto mapEntry = _fileInfoCache.at(row);
+    auto role = static_cast<DisplayedFilesModelRoles>(roleAsInt);
+    switch (role) {
+        case DisplayedFilesModelRoles::author:  // NOLINT(bugprone-branch-clone)
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::baseName:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::company:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::creationTime:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::description:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::license:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::modifiedTime:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::path:
+            [[fallthrough]];
+        case DisplayedFilesModelRoles::size:
+            if (mapEntry.find(role) != mapEntry.end()) {
+                return QString::fromStdString(mapEntry.at(role));
+            }
+            else {
+                return {};
+            }
+        case DisplayedFilesModelRoles::image: {
+            auto path = QString::fromStdString(mapEntry.at(DisplayedFilesModelRoles::path));
+            if (_imageCache.contains(path)) {
+                return _imageCache[path];
+            }
+            break;
+        }
+        default:
+            break;
+    }
+    switch (roleAsInt) {
+        case Qt::ItemDataRole::ToolTipRole:
+            return QString::fromStdString(mapEntry.at(DisplayedFilesModelRoles::path));
+    }
+    return {};
+}
+
+bool freecadCanOpen (const QString& extension)
+{
+    auto importTypes = App::GetApplication().getImportTypes();
+    return std::find(importTypes.begin(), importTypes.end(), extension.toStdString()) != importTypes.end();
+}
+
+void DisplayedFilesModel::addFile(const QString &filePath)
+{
+    QFileInfo qfi (filePath);
+    if (!qfi.isReadable()){
+        return;
+    }
+    if (!freecadCanOpen(qfi.suffix())) {
+        return;
+    }
+    _fileInfoCache.emplace_back(getFileInfo(filePath.toStdString()));
+    if (qfi.completeSuffix() == QLatin1String("FCStd")) {
+        auto thumbnail = loadFCStdThumbnail(filePath.toStdString());
+        if (!thumbnail.isEmpty()) {
+            _imageCache.insert(filePath, thumbnail);
+        }
+    }
+}
+
+void DisplayedFilesModel::clear()
+{
+    _fileInfoCache.clear();
+}
+
+QHash<int, QByteArray> DisplayedFilesModel::roleNames() const
+{
+    static QHash<int, QByteArray> nameMap {
+        std::make_pair(int(DisplayedFilesModelRoles::author), "author"),
+        std::make_pair(int(DisplayedFilesModelRoles::baseName), "baseName"),
+        std::make_pair(int(DisplayedFilesModelRoles::company), "company"),
+        std::make_pair(int(DisplayedFilesModelRoles::creationTime), "creationTime"),
+        std::make_pair(int(DisplayedFilesModelRoles::description), "description"),
+        std::make_pair(int(DisplayedFilesModelRoles::image), "image"),
+        std::make_pair(int(DisplayedFilesModelRoles::license), "license"),
+        std::make_pair(int(DisplayedFilesModelRoles::modifiedTime), "modifiedTime"),
+        std::make_pair(int(DisplayedFilesModelRoles::path), "path"),
+        std::make_pair(int(DisplayedFilesModelRoles::size), "size"),
+    };
+    return nameMap;
+}

src/Mod/CleanStart/App/DisplayedFilesModel.h

@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef FREECAD_CLEANSTART_DISPLAYEDFILESMODEL_H
+#define FREECAD_CLEANSTART_DISPLAYEDFILESMODEL_H
+
+#include <QAbstractListModel>
+#include <Base/Parameter.h>
+#include <QtQml/QQmlTypeInfo>
+
+#include "../CleanStartGlobal.h"
+
+namespace CleanStart
+{
+
+enum class DisplayedFilesModelRoles
+{
+    baseName = Qt::UserRole + 1,
+    image,
+    size,
+    author,
+    creationTime,
+    modifiedTime,
+    description,
+    company,
+    license,
+    path
+};
+
+using FileStats = std::map<DisplayedFilesModelRoles, std::string>;
+
+/// A model for displaying a list of files including a thumbnail or icon, plus various file statistics.
+class CleanStartExport DisplayedFilesModel: public QAbstractListModel
+{
+    Q_OBJECT
+public:
+    explicit DisplayedFilesModel(QObject* parent = nullptr);
+
+    int rowCount(const QModelIndex& parent = QModelIndex()) const override;
+
+    QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const override;
+
+    void addFile(const QString &filePath);
+
+    void clear();
+
+protected:
+    /// For communication with QML, define the text version of each role name defined in the
+    /// DisplayedFilesModelRoles enumeration
+    QHash<int, QByteArray> roleNames() const override;
+
+    /// Destroy and recreate the cache of info about the files. Should be connected to a signal
+    /// indicating when some piece of information about the files has changed. Does NOT generate
+    /// a new list of files, only re-caches the existing ones.
+    void reCacheFileInfo();
+
+private:
+
+    std::vector<FileStats> _fileInfoCache;
+    QMap<QString, QByteArray> _imageCache;
+};
+
+}  // namespace CleanStart
+
+#endif  // FREECAD_CLEANSTART_DISPLAYEDFILESMODEL_H

src/Mod/CleanStart/App/ExamplesModel.cpp

@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+#ifndef _PreComp_
+#include <QDir>
+#endif
+
+#include "ExamplesModel.h"
+#include <App/Application.h>
+
+using namespace CleanStart;
+
+FC_LOG_LEVEL_INIT(ExamplesModel)
+
+ExamplesModel::ExamplesModel(QObject* parent) : DisplayedFilesModel(parent)
+{
+    auto examplesPath = QDir(QString::fromStdString(App::Application::getResourceDir()));
+    _examplesDirectory.setPath (examplesPath.filePath(QLatin1String("examples")));
+}
+
+void ExamplesModel::loadExamples()
+{
+    beginResetModel();
+    clear();
+    if (!_examplesDirectory.isReadable()) {
+        Base::Console().Warning("Cannot read %s", _examplesDirectory.absolutePath().toStdString().c_str());
+    }
+    auto entries = _examplesDirectory.entryList(QDir::Filter::Files | QDir::Filter::Readable, QDir::SortFlag::Name);
+    for (const auto & entry : entries) {
+        addFile(_examplesDirectory.filePath(entry));
+    }
+    endResetModel();
+}

src/Mod/CleanStart/App/ExamplesModel.h

@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef FREECAD_CLEANSTART_EXAMPLESMODEL_H
+#define FREECAD_CLEANSTART_EXAMPLESMODEL_H
+
+#include <QAbstractListModel>
+#include <QDir>
+#include <Base/Parameter.h>
+#include <QtQml/QQmlTypeInfo>
+
+#include "DisplayedFilesModel.h"
+#include "../CleanStartGlobal.h"
+
+namespace CleanStart
+{
+
+/// A model for displaying a list of files including a thumbnail or icon, plus various file statistics.
+class CleanStartExport ExamplesModel: public DisplayedFilesModel
+{
+    Q_OBJECT
+public:
+    explicit ExamplesModel(QObject* parent = nullptr);
+
+    void loadExamples();
+
+private:
+    QDir _examplesDirectory;
+};
+
+}  // namespace CleanStart
+
+#endif  // FREECAD_CLEANSTART_EXAMPLESMODEL_H

src/Mod/CleanStart/App/PreCompiled.cpp

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+
+#include "PreCompiled.h"

src/Mod/CleanStart/App/PreCompiled.h

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef CLEANSTART_PRECOMPILED_H
+#define CLEANSTART_PRECOMPILED_H
+
+#include <FCConfig.h>
+
+#ifdef _MSC_VER
+#pragma warning(disable : 5208)
+#endif
+
+#ifdef _PreComp_
+
+// standard
+#include <cinttypes>
+#include <cmath>
+#include <iomanip>
+#include <map>
+#include <sstream>
+#include <string>
+#include <vector>
+#include <unordered_map>
+
+// Qt (should never include GUI files, only QtCore)
+#include <QDir>
+#include <QFile>
+#include <QFileInfo>
+
+#endif  // _PreComp_
+#endif  // CLEANSTART_PRECOMPILED_H

src/Mod/CleanStart/App/RecentFilesModel.cpp

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+#ifndef _PreComp_
+#endif
+
+#include "RecentFilesModel.h"
+#include <App/Application.h>
+#include <App/ProjectFile.h>
+
+using namespace CleanStart;
+
+RecentFilesModel::RecentFilesModel(QObject* parent) : DisplayedFilesModel(parent)
+{
+    _parameterGroup = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/RecentFiles");
+}
+
+void RecentFilesModel::loadRecentFiles()
+{
+    beginResetModel();
+    clear();
+    auto numRows {_parameterGroup->GetInt("RecentFiles", 0)};
+    for (int i = 0; i < numRows; ++i) {
+        auto entry = fmt::format("MRU{}", i);
+        auto path = _parameterGroup->GetASCII(entry.c_str(), "");
+        addFile(QString::fromStdString(path));
+    }
+    endResetModel();
+}

src/Mod/CleanStart/App/RecentFilesModel.h

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef FREECAD_CLEANSTART_RECENTFILESMODEL_H
+#define FREECAD_CLEANSTART_RECENTFILESMODEL_H
+
+#include <QAbstractListModel>
+#include <Base/Parameter.h>
+#include <QtQml/QQmlTypeInfo>
+
+#include "DisplayedFilesModel.h"
+#include "../CleanStartGlobal.h"
+
+namespace CleanStart
+{
+
+/// A model for displaying a list of files including a thumbnail or icon, plus various file statistics.
+class CleanStartExport RecentFilesModel: public DisplayedFilesModel
+{
+    Q_OBJECT
+public:
+    explicit RecentFilesModel(QObject* parent = nullptr);
+
+    void loadRecentFiles();
+
+private:
+    Base::Reference<ParameterGrp> _parameterGroup;
+};
+
+}  // namespace CleanStart
+
+#endif  // FREECAD_CLEANSTART_RECENTFILESMODEL_H

src/Mod/CleanStart/CMakeLists.txt

@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# /****************************************************************************
+#  *                                                                          *
+#  *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+#  *                                                                          *
+#  *   This file is part of FreeCAD.                                          *
+#  *                                                                          *
+#  *   FreeCAD is free software: you can redistribute it and/or modify it     *
+#  *   under the terms of the GNU Lesser General Public License as            *
+#  *   published by the Free Software Foundation, either version 2.1 of the   *
+#  *   License, or (at your option) any later version.                        *
+#  *                                                                          *
+#  *   FreeCAD 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       *
+#  *   Lesser General Public License for more details.                        *
+#  *                                                                          *
+#  *   You should have received a copy of the GNU Lesser General Public       *
+#  *   License along with FreeCAD. If not, see                                *
+#  *   <https://www.gnu.org/licenses/>.                                       *
+#  *                                                                          *
+#  ***************************************************************************/
+
+add_subdirectory(App)
+
+set(CleanStart_Scripts
+        Init.py
+        )
+
+if (BUILD_GUI)
+    add_subdirectory(Gui)
+    list(APPEND CleanStart_Scripts InitGui.py)
+endif (BUILD_GUI)
+
+add_custom_target(CleanStartScripts ALL
+        SOURCES ${CleanStart_Scripts}
+        )
+
+fc_target_copy_resource(CleanStartScripts
+        ${CMAKE_CURRENT_SOURCE_DIR}
+        ${CMAKE_BINARY_DIR}/Mod/CleanStart
+        ${CleanStart_Scripts})
+
+INSTALL(
+        FILES
+        ${CleanStart_Scripts}
+        DESTINATION
+        Mod/CleanStart
+)

src/Mod/CleanStart/CleanStartGlobal.h

@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include <FCGlobal.h>
+
+#ifndef LAUNCHER_GLOBAL_H
+#define LAUNCHER_GLOBAL_H
+
+
+// CleanStart
+#ifndef CleanStartExport
+#ifdef CleanStart_EXPORTS
+#define CleanStartExport FREECAD_DECL_EXPORT
+#else
+#define CleanStartExport FREECAD_DECL_IMPORT
+#endif
+#endif
+
+// CleanStartGui
+#ifndef CleanStartGuiExport
+#ifdef CleanStartGui_EXPORTS
+#define CleanStartGuiExport FREECAD_DECL_EXPORT
+#else
+#define CleanStartGuiExport FREECAD_DECL_IMPORT
+#endif
+#endif
+
+#endif  // LAUNCHER_GLOBAL_H

src/Mod/CleanStart/Gui/AppCleanStartGui.cpp

@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+
+#include <Base/Console.h>
+#include <Base/Interpreter.h>
+#include <Base/PyObjectBase.h>
+#include <Gui/Language/Translator.h>
+
+#include <QString>
+
+#include <3rdParty/GSL/include/gsl/pointers>
+
+#include "Workbench.h"
+
+void loadCleanStartResource()
+{
+    // add resources and reloads the translators
+    Q_INIT_RESOURCE(CleanStart);
+    Q_INIT_RESOURCE(CleanStart_translation);
+    Gui::Translator::instance()->refresh();
+}
+
+namespace CleanStartGui
+{
+    extern PyObject* initModule();
+}
+
+
+namespace CleanStartGui
+{
+class Module: public Py::ExtensionModule<Module>
+{
+public:
+    Module()
+        : Py::ExtensionModule<Module>("CleanStartGui")
+    {
+        initialize("This module is the CleanStartGui module.");  // register with Python
+    }
+};
+
+PyObject* initModule()
+{
+    auto newModule = gsl::owner<Module*>(new Module);
+    return Base::Interpreter().addModule(newModule);  // Transfer ownership
+}
+
+}  // namespace CleanStartGui
+
+/* Python entry */
+PyMOD_INIT_FUNC(CleanStartGui)
+{
+    Base::Console().Log("Loading GUI of CleanStart module... ");
+    PyObject* mod = CleanStartGui::initModule();
+    CleanStartGui::Workbench::init();
+    loadCleanStartResource();
+    Base::Console().Log("done\n");
+
+    PyMOD_Return(mod);
+}

src/Mod/CleanStart/Gui/CMakeLists.txt

@@ -0,0 +1,89 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# /****************************************************************************
+#  *                                                                          *
+#  *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+#  *                                                                          *
+#  *   This file is part of FreeCAD.                                          *
+#  *                                                                          *
+#  *   FreeCAD is free software: you can redistribute it and/or modify it     *
+#  *   under the terms of the GNU Lesser General Public License as            *
+#  *   published by the Free Software Foundation, either version 2.1 of the   *
+#  *   License, or (at your option) any later version.                        *
+#  *                                                                          *
+#  *   FreeCAD 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       *
+#  *   Lesser General Public License for more details.                        *
+#  *                                                                          *
+#  *   You should have received a copy of the GNU Lesser General Public       *
+#  *   License along with FreeCAD. If not, see                                *
+#  *   <https://www.gnu.org/licenses/>.                                       *
+#  *                                                                          *
+#  ***************************************************************************/
+
+include_directories(
+        ${CMAKE_CURRENT_BINARY_DIR}
+        ${PYTHON_INCLUDE_DIRS}
+        ${Boost_INCLUDE_DIRS}
+        ${ZLIB_INCLUDE_DIR}
+        ${XercesC_INCLUDE_DIRS}
+        ${QtCore_INCLUDE_DIRS}
+        ${QtWidgets_INCLUDE_DIRS}
+        ${QtSvg_INCLUDE_DIRS}
+        #${QtNetwork_INCLUDE_DIRS}
+        ${QtUiTools_INCLUDE_DIRS}
+        #${QtQuick_INCLUDE_DIRS}
+        #${QtQuickWidgets_INCLUDE_DIRS}
+)
+
+set(CleanStartGui_LIBS
+        CleanStart
+        FreeCADGui
+        )
+
+set(CleanStart_TR_QRC ${CMAKE_CURRENT_BINARY_DIR}/Resources/CleanStart_translation.qrc)
+qt_find_and_add_translation(QM_SRCS "Resources/translations/*_*.ts"
+        ${CMAKE_CURRENT_BINARY_DIR}/Resources/translations)
+qt_create_resource_file(${CleanStart_TR_QRC} ${QM_SRCS})
+qt_add_resources(CleanStart_QRC_SRCS Resources/CleanStart.qrc ${CleanStart_TR_QRC})
+# qtquick_compiler_add_resources(CleanStart_QRC_SRCS Resources/CleanStart.qrc ${CleanStart_TR_QRC} qml.qrc)
+
+SET(CleanStartGui_SRCS
+        ${CleanStart_QRC_SRCS}
+        ${CleanStartGui_UIC_SRCS}
+        AppCleanStartGui.cpp
+        Command.cpp
+        PreCompiled.cpp
+        PreCompiled.h
+        CleanStartView.cpp
+        CleanStartView.h
+        FileCardDelegate.cpp
+        FileCardDelegate.h
+        FileCardView.cpp
+        FileCardView.h
+        Workbench.cpp
+        Workbench.h
+        )
+
+SET(CleanStartGuiIcon_SVG
+        Resources/icons/CleanStartWorkbench.svg
+        )
+
+# TODO: Evaluate PCH use with Qt6/QtQuick/Qml
+if (FREECAD_USE_PCH)
+    add_definitions(-D_PreComp_)
+    GET_MSVC_PRECOMPILED_SOURCE("PreCompiled.cpp" PCH_SRCS ${CleanStartGui_SRCS})
+    ADD_MSVC_PRECOMPILED_HEADER(CleanStartGui PreCompiled.h PreCompiled.cpp PCH_SRCS)
+endif (FREECAD_USE_PCH)
+
+add_library(CleanStartGui SHARED ${CleanStartGui_SRCS} ${CleanStartGuiIcon_SVG})
+# target_link_libraries(CleanStartGui ${CleanStartGui_LIBS} Qt::Quick Qt::Qml Qt::QuickWidgets)
+target_link_libraries(CleanStartGui ${CleanStartGui_LIBS})
+
+SET_BIN_DIR(CleanStartGui CleanStartGui /Mod/CleanStart)
+SET_PYTHON_PREFIX_SUFFIX(CleanStartGui)
+
+fc_copy_sources(CleanStartGui "${CMAKE_BINARY_DIR}/${CMAKE_INSTALL_DATADIR}/Mod/CleanStart" ${CleanStartGuiIcon_SVG})
+
+INSTALL(TARGETS CleanStartGui DESTINATION ${CMAKE_INSTALL_LIBDIR})
+INSTALL(FILES ${CleanStartGuiIcon_SVG} DESTINATION "${CMAKE_INSTALL_DATADIR}/Mod/CleanStart/Resources/icons")

src/Mod/CleanStart/Gui/CleanStartView.cpp

@@ -0,0 +1,298 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+#ifndef _PreComp_
+#include <QCoreApplication>
+#include <QGridLayout>
+#include <QLabel>
+#include <QListView>
+#include <QPushButton>
+#include <QScrollArea>
+#include <QWidget>
+#endif
+
+#include "CleanStartView.h"
+#include "FileCardDelegate.h"
+#include "FileCardView.h"
+#include "Gui/Workbench.h"
+#include <Gui/Document.h>
+#include <App/DocumentObject.h>
+#include <App/Application.h>
+#include <Base/Interpreter.h>
+#include <Gui/Application.h>
+#include <Gui/Command.h>
+#include <3rdParty/GSL/include/gsl/pointers>
+
+using namespace CleanStartGui;
+
+TYPESYSTEM_SOURCE_ABSTRACT(CleanStartGui::CleanStartView, Gui::MDIView)  // NOLINT
+
+namespace {
+
+struct NewButton
+{
+    QString heading;
+    QString description;
+    QString iconPath;
+};
+
+gsl::owner<QPushButton*> createNewButton(const NewButton& newButton)
+{
+    auto hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/Mod/Start");
+    const auto cardSpacing = static_cast<int>(hGrp->GetInt("FileCardSpacing", 20));      // NOLINT
+    const auto newFileIconSize = static_cast<int>(hGrp->GetInt("NewFileIconSize", 48));  // NOLINT
+
+    auto button = gsl::owner<QPushButton*>(new QPushButton());
+    auto mainLayout = gsl::owner<QHBoxLayout*>(new QHBoxLayout(button));
+    auto iconLabel = gsl::owner<QLabel*>(new QLabel(button));
+    mainLayout->addWidget(iconLabel);
+    QIcon baseIcon(newButton.iconPath);
+    iconLabel->setPixmap(baseIcon.pixmap(newFileIconSize, newFileIconSize));
+
+    auto textLayout = gsl::owner<QVBoxLayout*>(new QVBoxLayout);
+    auto textLabelLine1 = gsl::owner<QLabel*>(new QLabel(button));
+    textLabelLine1->setText(QLatin1String("<b>") + newButton.heading + QLatin1String("</b>"));
+    auto textLabelLine2 = gsl::owner<QLabel*>(new QLabel(button));
+    textLabelLine2->setText(newButton.description);
+    textLabelLine2->setWordWrap(true);
+    textLayout->addWidget(textLabelLine1);
+    textLayout->addWidget(textLabelLine2);
+    textLayout->setSpacing(0);
+    mainLayout->addItem(textLayout);
+
+    mainLayout->addStretch();
+
+    button->setMinimumHeight(newFileIconSize + cardSpacing);
+    return button;
+}
+
+}
+
+CleanStartView::CleanStartView(Gui::Document* pcDocument, QWidget* parent)
+    : Gui::MDIView(pcDocument, parent)
+    , _contents(new QScrollArea(parent))
+{
+    setObjectName(QLatin1String("CleanStartView"));
+    auto hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/Mod/Start");
+    auto cardSpacing = hGrp->GetInt("FileCardSpacing", 20);  // NOLINT
+
+    auto scrolledWidget = gsl::owner<QWidget*>(new QWidget(this));
+    _contents->setWidget(scrolledWidget);
+    _contents->setHorizontalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAlwaysOff);
+    _contents->setVerticalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAsNeeded);
+    _contents->setWidgetResizable(true);
+    auto layout = gsl::owner<QVBoxLayout*>(new QVBoxLayout(scrolledWidget));
+    layout->setSizeConstraint(QLayout::SizeConstraint::SetMinAndMaxSize);
+
+    auto newFileLabel = gsl::owner<QLabel*>(new QLabel(tr("New File")));
+    layout->addWidget(newFileLabel);
+    auto gridLayout = gsl::owner<QGridLayout*>(new QGridLayout);
+    layout->addLayout(gridLayout);
+    configureNewFileButtons(gridLayout);
+
+    auto recentFilesLabel = gsl::owner<QLabel*>(new QLabel(tr("Recent Files")));
+    layout->addWidget(recentFilesLabel);
+    auto recentFilesListWidget = gsl::owner<FileCardView*>(new FileCardView(_contents));
+    connect(recentFilesListWidget, &QListView::clicked, this, &CleanStartView::fileCardSelected);
+    layout->addWidget(recentFilesListWidget);
+
+    auto examplesLabel = gsl::owner<QLabel*>(new QLabel(tr("Examples")));
+    layout->addWidget(examplesLabel);
+    auto examplesListWidget = gsl::owner<FileCardView*>(new FileCardView(_contents));
+    connect(examplesListWidget, &QListView::clicked, this, &CleanStartView::fileCardSelected);
+    layout->addWidget(examplesListWidget);
+
+    layout->setSpacing(static_cast<int>(cardSpacing));
+    layout->addStretch();
+
+    setCentralWidget(_contents);
+
+    QString title = QCoreApplication::translate("Workbench", "Start");
+    setWindowTitle(title);
+
+    configureExamplesListWidget(examplesListWidget);
+    configureRecentFilesListWidget(recentFilesListWidget);
+}
+
+
+void CleanStartView::configureNewFileButtons(QGridLayout* layout) const
+{
+    auto newEmptyFile = createNewButton({tr("Empty file"),
+                                         tr("Create a new empty FreeCAD file"),
+                                         QLatin1String(":/icons/document-new.svg")});
+    auto openFile = createNewButton({tr("Open File"),
+                                     tr("Open an existing CAD file or 3D model"),
+                                     QLatin1String(":/icons/document-open.svg")});
+    auto partDesign = createNewButton({tr("Parametric Part"),
+                                       tr("Create a part with the Part Design workbench"),
+                                       QLatin1String(":/icons/PartDesignWorkbench.svg")});
+    auto assembly = createNewButton({tr("Assembly"),
+                                     tr("Create an assembly project"),
+                                     QLatin1String(":/icons/AssemblyWorkbench.svg")});
+    auto draft = createNewButton({tr("2D Draft"),
+                                  tr("Create a 2D Draft with the Draft workbench"),
+                                  QLatin1String(":/icons/DraftWorkbench.svg")});
+    auto arch = createNewButton({tr("BIM/Architecture"),
+                                 tr("Create an architectural project"),
+                                 QLatin1String(":/icons/ArchWorkbench.svg")});
+
+    layout->addWidget(partDesign, 0, 0);
+    layout->addWidget(assembly, 0, 1);
+    layout->addWidget(draft, 0, 2);
+    layout->addWidget(arch, 1, 0);
+    layout->addWidget(newEmptyFile, 1, 1);
+    layout->addWidget(openFile, 1, 2);
+
+    connect(newEmptyFile, &QPushButton::clicked, this, &CleanStartView::newEmptyFile);
+    connect(openFile, &QPushButton::clicked, this, &CleanStartView::openExistingFile);
+    connect(partDesign, &QPushButton::clicked, this, &CleanStartView::newPartDesignFile);
+    connect(assembly, &QPushButton::clicked, this, &CleanStartView::newAssemblyFile);
+    connect(draft, &QPushButton::clicked, this, &CleanStartView::newDraftFile);
+    connect(arch, &QPushButton::clicked, this, &CleanStartView::newArchFile);
+}
+
+void CleanStartView::configureFileCardWidget(QListView* fileCardWidget)
+{
+    auto delegate = gsl::owner<FileCardDelegate*>(new FileCardDelegate);
+    fileCardWidget->setItemDelegate(delegate);
+    fileCardWidget->setMinimumWidth(fileCardWidget->parentWidget()->width());
+    fileCardWidget->setGridSize(
+        fileCardWidget->itemDelegate()->sizeHint(QStyleOptionViewItem(),
+                                                 fileCardWidget->model()->index(0, 0)));
+}
+
+
+void CleanStartView::configureRecentFilesListWidget(QListView* recentFilesListWidget)
+{
+    _recentFilesModel.loadRecentFiles();
+    recentFilesListWidget->setModel(&_recentFilesModel);
+    configureFileCardWidget(recentFilesListWidget);
+}
+
+
+void CleanStartView::configureExamplesListWidget(QListView* examplesListWidget)
+{
+    _examplesModel.loadExamples();
+    examplesListWidget->setModel(&_examplesModel);
+    configureFileCardWidget(examplesListWidget);
+}
+
+
+void CleanStartView::newEmptyFile() const
+{
+    Gui::Application::Instance->commandManager().runCommandByName("Std_New");
+    postStart(PostStartBehavior::switchWorkbench);
+}
+
+void CleanStartView::newPartDesignFile() const
+{
+    Gui::Application::Instance->commandManager().runCommandByName("Std_New");
+    Gui::Application::Instance->activateWorkbench("PartDesignWorkbench");
+    Gui::Application::Instance->commandManager().runCommandByName("PartDesign_Body");
+    postStart(PostStartBehavior::doNotSwitchWorkbench);
+}
+
+void CleanStartView::openExistingFile() const
+{
+    auto originalDocument = Gui::Application::Instance->activeDocument();
+    Gui::Application::Instance->commandManager().runCommandByName("Std_Open");
+    if (Gui::Application::Instance->activeDocument() != originalDocument) {
+        // Only run this if the user chose a new document to open (that is, they didn't cancel the
+        // open file dialog)
+        postStart(PostStartBehavior::switchWorkbench);
+    }
+}
+
+void CleanStartView::newAssemblyFile() const
+{
+    Gui::Application::Instance->commandManager().runCommandByName("Std_New");
+    Gui::Application::Instance->activateWorkbench("AssemblyWorkbench");
+    Gui::Application::Instance->commandManager().runCommandByName("Assembly_CreateAssembly");
+    Gui::Application::Instance->commandManager().runCommandByName("Std_Refresh");
+    postStart(PostStartBehavior::doNotSwitchWorkbench);
+}
+
+void CleanStartView::newDraftFile() const
+{
+    Gui::Application::Instance->commandManager().runCommandByName("Std_New");
+    Gui::Application::Instance->activateWorkbench("DraftWorkbench");
+    Gui::Application::Instance->commandManager().runCommandByName("Std_ViewTop");
+    postStart(PostStartBehavior::doNotSwitchWorkbench);
+}
+
+void CleanStartView::newArchFile() const
+{
+    Gui::Application::Instance->commandManager().runCommandByName("Std_New");
+    try {
+        Gui::Application::Instance->activateWorkbench("BIMWorkbench");
+    }
+    catch (...) {
+        Gui::Application::Instance->activateWorkbench("ArchWorkbench");
+    }
+    postStart(PostStartBehavior::doNotSwitchWorkbench);
+}
+
+void CleanStartView::postStart(PostStartBehavior behavior) const
+{
+    auto hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/Mod/Start");
+
+    if (behavior == PostStartBehavior::switchWorkbench) {
+        auto wb = hGrp->GetASCII("AutoloadModule", "");
+        if (wb == "$LastModule") {
+            wb = App::GetApplication()
+                     .GetParameterGroupByPath("User parameter:BaseApp/Preferences/General")
+                     ->GetASCII("LastModule", "");
+        }
+        if (!wb.empty()) {
+            Gui::Application::Instance->activateWorkbench(wb.c_str());
+        }
+    }
+    auto closeStart = hGrp->GetBool("closeStart", false);
+    if (closeStart) {
+        this->window()->close();
+    }
+}
+
+
+void CleanStartView::fileCardSelected(const QModelIndex& index)
+{
+    auto file = index.data(static_cast<int>(CleanStart::DisplayedFilesModelRoles::path)).toString();
+    auto command = std::string("FreeCAD.loadFile('") + file.toStdString() + "')";
+    try {
+        Base::Interpreter().runString(command.c_str());
+        postStart(PostStartBehavior::doNotSwitchWorkbench);
+    }
+    catch (Base::PyException& e) {
+        Base::Console().Error(e.getMessage().c_str());
+    }
+    catch (Base::Exception &e) {
+        Base::Console().Error(e.getMessage().c_str());
+    }
+    catch (...) {
+        Base::Console().Error("An unknown error occurred");
+    }
+}

src/Mod/CleanStart/Gui/CleanStartView.h

@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef FREECAD_CLEANSTARTVIEW_H
+#define FREECAD_CLEANSTARTVIEW_H
+
+#include <Mod/CleanStart/CleanStartGlobal.h>
+#include <Base/Type.h>
+#include <Gui/MDIView.h>
+
+#include "../App/DisplayedFilesModel.h"
+#include "../App/RecentFilesModel.h"
+#include "../App/ExamplesModel.h"
+
+
+class QListView;
+class QGridLayout;
+class QScrollArea;
+
+namespace Gui
+{
+class Document;
+}
+
+namespace CleanStartGui
+{
+
+class CleanStartGuiExport CleanStartView: public Gui::MDIView
+{
+    Q_OBJECT
+
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();  // NOLINT
+
+public:
+    CleanStartView(Gui::Document* pcDocument, QWidget* parent);
+
+    const char* getName() const override
+    {
+        return "CleanStartView";
+    }
+
+    void newEmptyFile() const;
+    void newPartDesignFile() const;
+    void openExistingFile() const;
+    void newAssemblyFile() const;
+    void newDraftFile() const;
+    void newArchFile() const;
+
+public:
+    enum class PostStartBehavior {
+        switchWorkbench,
+        doNotSwitchWorkbench
+    };
+
+protected:
+
+    void configureNewFileButtons(QGridLayout *layout) const;
+    static void configureFileCardWidget(QListView *fileCardWidget);
+    void configureRecentFilesListWidget(QListView *recentFilesListWidget);
+    void configureExamplesListWidget(QListView *examplesListWidget);
+
+    void postStart(PostStartBehavior behavior) const;
+
+    void fileCardSelected(const QModelIndex &index);
+
+private:
+    QScrollArea* _contents = nullptr;
+    CleanStart::RecentFilesModel _recentFilesModel;
+    CleanStart::ExamplesModel _examplesModel;
+
+
+};  // namespace CleanStartGui
+
+}  // namespace CleanStartGui
+
+#endif  // FREECAD_CLEANSTARTVIEW_H

src/Mod/CleanStart/Gui/Command.cpp

@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+
+#include <Gui/Application.h>
+#include <Gui/Command.h>
+
+#include <3rdParty/GSL/include/gsl/pointers>
+
+#include "Workbench.h"
+
+
+using namespace std;
+
+DEF_STD_CMD(CmdCleanStart)
+
+CmdCleanStart::CmdCleanStart()
+    : Command("CleanStart_CleanStart")
+{
+    sAppModule = "CleanStart";
+    sGroup = QT_TR_NOOP("CleanStart");
+    sMenuText = QT_TR_NOOP("CleanStart");
+    sToolTipText = QT_TR_NOOP("Displays the CleanStart in an MDI view");
+    sWhatsThis = "CleanStart_CleanStart";
+    sStatusTip = sToolTipText;
+    sPixmap = "CleanStartWorkbench";
+}
+
+void CmdCleanStart::activated(int iMsg)
+{
+    Q_UNUSED(iMsg);
+    CleanStartGui::Workbench::loadCleanStart();
+}
+
+
+void CreateCleanStartCommands()
+{
+    Gui::CommandManager& rcCmdMgr = Gui::Application::Instance->commandManager();
+    auto newCommand = gsl::owner<CmdCleanStart*>(new CmdCleanStart);
+    rcCmdMgr.addCommand(newCommand);  // Transfer ownership
+}

src/Mod/CleanStart/Gui/FileCardDelegate.cpp

@@ -0,0 +1,148 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+
+#ifndef _PreComp_
+#include <QFile>
+#include <QFileIconProvider>
+#include <QImageReader>
+#include <QPainter>
+#include <QStyleOptionViewItem>
+#include <QLabel>
+#include <QModelIndex>
+#include <QVBoxLayout>
+#include <QGuiApplication>
+#endif
+
+#include "FileCardDelegate.h"
+#include "../App/DisplayedFilesModel.h"
+#include "App/Application.h"
+#include <3rdParty/GSL/include/gsl/pointers>
+
+using namespace CleanStart;
+
+FileCardDelegate::FileCardDelegate(QObject *parent)
+        : QAbstractItemDelegate(parent) {
+    _parameterGroup = App::GetApplication().GetParameterGroupByPath(
+            "User parameter:BaseApp/Preferences/Mod/Start");
+}
+
+
+void FileCardDelegate::paint(QPainter *painter,
+                             const QStyleOptionViewItem &option,
+                             const QModelIndex &index) const {
+    auto thumbnailSize =
+            static_cast<int>(_parameterGroup->GetInt("FileThumbnailIconsSize", 64));  // NOLINT
+    auto cardWidth = thumbnailSize;
+    auto baseName = index.data(static_cast<int>(DisplayedFilesModelRoles::baseName)).toString();
+    auto size = index.data(static_cast<int>(DisplayedFilesModelRoles::size)).toString();
+    auto image = index.data(static_cast<int>(DisplayedFilesModelRoles::image)).toByteArray();
+    auto path = index.data(static_cast<int>(DisplayedFilesModelRoles::path)).toString();
+    painter->save();
+    auto widget = gsl::owner<QWidget *>(new QWidget());
+    auto layout = gsl::owner<QVBoxLayout *>(new QVBoxLayout());
+    widget->setLayout(layout);
+    auto thumbnail = gsl::owner<QLabel *>(new QLabel());
+    auto pixmap = gsl::owner<QPixmap *>(new QPixmap());
+    if (!image.isEmpty()) {
+        pixmap->loadFromData(image);
+        auto scaled = pixmap->scaled(QSize(thumbnailSize, thumbnailSize),
+                                     Qt::AspectRatioMode::KeepAspectRatio,
+                                     Qt::TransformationMode::SmoothTransformation);
+        thumbnail->setPixmap(scaled);
+    } else {
+        thumbnail->setPixmap(generateThumbnail(path));
+    }
+    thumbnail->setFixedSize(thumbnailSize, thumbnailSize);
+    thumbnail->setSizePolicy(QSizePolicy::Policy::Fixed, QSizePolicy::Policy::Fixed);
+    auto elided =
+            painter->fontMetrics().elidedText(baseName, Qt::TextElideMode::ElideRight, cardWidth);
+    auto name = gsl::owner<QLabel *>(new QLabel(elided));
+    layout->addWidget(thumbnail);
+    layout->addWidget(name);
+    auto sizeLabel = gsl::owner<QLabel *>(new QLabel(size));
+    layout->addWidget(sizeLabel);
+    layout->addStretch();
+    layout->setSpacing(0);
+    widget->resize(option.rect.size());
+    painter->translate(option.rect.topLeft());
+    widget->render(painter, QPoint(), QRegion(), QWidget::DrawChildren);
+    painter->restore();
+    delete pixmap;
+}
+
+
+QSize FileCardDelegate::sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const {
+    Q_UNUSED(option)
+    Q_UNUSED(index)
+    auto thumbnailSize = _parameterGroup->GetInt("FileThumbnailIconsSize", 128);  // NOLINT
+    auto cardSpacing = _parameterGroup->GetInt("FileCardSpacing", 20);           // NOLINT
+    auto cardWidth = thumbnailSize + cardSpacing;
+
+    auto font = QGuiApplication::font();
+    auto qfm = QFontMetrics(font);
+    auto textHeight = 2 * qfm.lineSpacing();
+    auto cardHeight = thumbnailSize + textHeight + cardSpacing;
+
+    return {static_cast<int>(cardWidth), static_cast<int>(cardHeight)};
+}
+
+namespace {
+    QPixmap pixmapToSizedQImage(const QImage &pixmap, int size) {
+        return QPixmap::fromImage(pixmap).scaled(size, size,
+                                                 Qt::AspectRatioMode::KeepAspectRatio,
+                                                 Qt::TransformationMode::SmoothTransformation);
+    }
+}
+
+QPixmap FileCardDelegate::generateThumbnail(const QString &path) const {
+    auto thumbnailSize =
+            static_cast<int>(_parameterGroup->GetInt("FileThumbnailIconsSize", 64));  // NOLINT
+    if (path.endsWith(QLatin1String(".fcstd"), Qt::CaseSensitivity::CaseInsensitive)) {
+        QImageReader reader(QLatin1String(":/icons/freecad-doc.svg"));;
+        reader.setScaledSize({thumbnailSize, thumbnailSize});
+        return QPixmap::fromImage(reader.read());
+    }
+    if (path.endsWith(QLatin1String(".fcmacro"), Qt::CaseSensitivity::CaseInsensitive)) {
+        QImageReader reader(QLatin1String(":/icons/MacroEditor.svg"));;
+        reader.setScaledSize({thumbnailSize, thumbnailSize});
+        return QPixmap::fromImage(reader.read());
+    }
+    if (!QImageReader::imageFormat(path).isEmpty()) {
+        // It is an image: it can be its own thumbnail
+        QImageReader reader(path);
+        auto image = reader.read();
+        return pixmapToSizedQImage(image, thumbnailSize);
+    }
+    QIcon icon = QFileIconProvider().icon(QFileInfo(path));
+    if (!icon.isNull()) {
+        QPixmap pixmap = icon.pixmap(thumbnailSize);
+        if (!pixmap.isNull()) {
+            return pixmap;
+        }
+    }
+    QPixmap pixmap = QPixmap(thumbnailSize, thumbnailSize);
+    pixmap.fill();
+    return pixmap;
+}

src/Mod/CleanStart/Gui/FileCardDelegate.h

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef FREECAD_CLEANSTART_FILECARDDELEGATE_H
+#define FREECAD_CLEANSTART_FILECARDDELEGATE_H
+
+#include <Base/Parameter.h>
+#include <QImage>
+
+#include <QAbstractItemDelegate>
+
+class FileCardDelegate : public QAbstractItemDelegate {
+
+public:
+
+    explicit FileCardDelegate(QObject *parent = nullptr);
+
+    void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const override;
+
+    QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const override;
+
+protected:
+
+    QPixmap generateThumbnail(const QString &path) const;
+
+private:
+
+    Base::Reference<ParameterGrp> _parameterGroup;
+};
+
+
+#endif //FREECAD_CLEANSTART_FILECARDDELEGATE_H

src/Mod/CleanStart/Gui/FileCardView.cpp

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+#include "FileCardView.h"
+
+#include <App/Application.h>
+#include "../App/DisplayedFilesModel.h"
+
+namespace CleanStartGui
+{
+
+
+FileCardView::FileCardView(QWidget *parent) : QListView(parent)
+{
+    QSizePolicy sizePolicy(QSizePolicy::Policy::MinimumExpanding,
+                           QSizePolicy::Policy::MinimumExpanding);
+    sizePolicy.setHeightForWidth(true);
+    setSizePolicy(sizePolicy);
+    setHorizontalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAlwaysOff);
+    setVerticalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAlwaysOff);
+    setViewMode(QListView::ViewMode::IconMode);
+    setFlow(QListView::Flow::LeftToRight);
+    setResizeMode(QListView::ResizeMode::Adjust);
+    setUniformItemSizes(true);
+}
+
+int FileCardView::heightForWidth(int width) const
+{
+    auto model = this->model();
+    auto delegate = this->itemDelegate();
+    if (!model || !delegate) {
+        return 0;
+    }
+    int numCards = model->rowCount();
+    auto cardSize = delegate->sizeHint(QStyleOptionViewItem(), model->index(0, 0));
+    int cardsPerRow = static_cast<int>(width / cardSize.width());
+    int numRows = static_cast<int> (ceil(static_cast<double>(numCards) / static_cast<double>(cardsPerRow)));
+    int neededHeight = numRows * cardSize.height();
+    auto hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/Mod/Start");
+    int cardSpacing = static_cast<int>(hGrp->GetInt("FileCardSpacing", 20));  // NOLINT
+    return neededHeight + cardSpacing*(numRows-1) + 2*cardSpacing;
+}
+
+QSize FileCardView::sizeHint() const
+{
+    auto hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/Mod/Start");
+    int cardSpacing = static_cast<int>(hGrp->GetInt("FileCardSpacing", 20));  // NOLINT
+
+    auto model = this->model();
+    auto delegate = this->itemDelegate();
+    if (!model || !delegate) {
+        // The model and/or delegate have not been set yet, this was an early startup call
+        return {cardSpacing, cardSpacing};
+    }
+    int numCards = model->rowCount();
+    auto cardSize = delegate->sizeHint(QStyleOptionViewItem(), model->index(0, 0));
+    return {(cardSize.width()+cardSpacing) * numCards + cardSpacing, cardSize.height() + 2* cardSpacing};
+}
+
+
+}  // namespace CleanStart

src/Mod/CleanStart/Gui/FileCardView.h

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef FREECAD_CLEANSTART_FILECARDVIEW_H
+#define FREECAD_CLEANSTART_FILECARDVIEW_H
+
+#include <QListView>
+
+namespace CleanStartGui
+{
+
+class FileCardView : public QListView
+{
+    Q_OBJECT
+
+public:
+    explicit FileCardView(QWidget *parent = nullptr);
+
+    int heightForWidth(int width) const override;
+
+    QSize sizeHint() const override;
+
+};
+
+}  // namespace CleanStart
+
+#endif  // FREECAD_CLEANSTART_FILECARDVIEW_H

src/Mod/CleanStart/Gui/PreCompiled.cpp

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+
+#include "PreCompiled.h"

src/Mod/CleanStart/Gui/PreCompiled.h

@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#ifndef CLEANSTARTGUI_PRECOMPILED_H
+#define CLEANSTARTGUI_PRECOMPILED_H
+
+#include <FCConfig.h>
+
+#ifdef _MSC_VER
+#pragma warning(disable : 5208)
+#endif
+
+#ifdef _PreComp_
+
+// standard
+#include <cinttypes>
+#include <cmath>
+#include <iomanip>
+#include <map>
+#include <sstream>
+#include <string>
+#include <vector>
+#include <unordered_map>
+
+// Qt
+#include <QCoreApplication>
+#include <QFile>
+#include <QFileIconProvider>
+#include <QGridLayout>
+#include <QGuiApplication>
+#include <QImageReader>
+#include <QLabel>
+#include <QListView>
+#include <QModelIndex>
+#include <QPainter>
+#include <QPushButton>
+#include <QScrollArea>
+#include <QSpacerItem>
+#include <QStyleOptionViewItem>
+#include <QUrl>
+#include <QVBoxLayout>
+#include <QWidget>
+
+#endif  // _PreComp_
+#endif  // CLEANSTARTGUI_PRECOMPILED_H

src/Mod/CleanStart/Gui/Resources/CleanStart.qrc

@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/">
+        <file>icons/CleanStartWorkbench.svg</file>
+    </qresource>
+</RCC>

src/Mod/CleanStart/Gui/Workbench.cpp

@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+#include "PreCompiled.h"
+#ifndef _PreComp_
+#include <QCoreApplication>
+#include <QLayout>
+#endif
+
+#include <Base/Console.h>
+#include <Base/Exception.h>
+#include <Gui/Command.h>
+#include <Gui/DockWindowManager.h>
+#include <Gui/MDIView.h>
+#include <Gui/MainWindow.h>
+#include <Gui/ToolBarManager.h>
+
+#include "Workbench.h"
+#include "CleanStartView.h"
+
+#include <3rdParty/GSL/include/gsl/pointers>
+
+using namespace CleanStartGui;
+
+TYPESYSTEM_SOURCE(CleanStartGui::Workbench, Gui::StdWorkbench)  // NOLINT
+
+void CleanStartGui::Workbench::activated()
+{
+    loadCleanStart();
+}
+
+void CleanStartGui::Workbench::loadCleanStart()
+{
+    auto mw = Gui::getMainWindow();
+    auto doc = Gui::Application::Instance->activeDocument();
+    auto existingView = mw->findChild<CleanStartView*>(QLatin1String("CleanStartView"));
+    if (!existingView) {
+        existingView = gsl::owner<CleanStartView*> (new CleanStartView (doc, mw));
+        mw->addWindow(existingView);  // Transfers ownership
+    }
+    Gui::getMainWindow()->setActiveWindow(existingView);
+    existingView->show();
+}
+
+Gui::MenuItem* CleanStartGui::Workbench::setupMenuBar() const
+{
+    return Gui::StdWorkbench::setupMenuBar();
+}
+
+Gui::ToolBarItem* CleanStartGui::Workbench::setupToolBars() const
+{
+    return Gui::StdWorkbench::setupToolBars();
+}
+
+Gui::ToolBarItem* CleanStartGui::Workbench::setupCommandBars() const
+{
+    return Gui::StdWorkbench::setupCommandBars();
+}
+
+Gui::DockWindowItems* CleanStartGui::Workbench::setupDockWindows() const
+{
+    Gui::DockWindowItems* root = Gui::StdWorkbench::setupDockWindows();
+    root->setVisibility(false);                  // hide all dock windows by default
+    root->setVisibility("Std_ComboView", true);  // except of the combo view
+    root->setVisibility("Std_TaskView", true);   // and the task view
+    return root;
+}

src/Mod/CleanStart/Gui/Workbench.h

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: LGPL-2.1-or-later
+/****************************************************************************
+ *                                                                          *
+ *   Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+ *                                                                          *
+ *   This file is part of FreeCAD.                                          *
+ *                                                                          *
+ *   FreeCAD is free software: you can redistribute it and/or modify it     *
+ *   under the terms of the GNU Lesser General Public License as            *
+ *   published by the Free Software Foundation, either version 2.1 of the   *
+ *   License, or (at your option) any later version.                        *
+ *                                                                          *
+ *   FreeCAD 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       *
+ *   Lesser General Public License for more details.                        *
+ *                                                                          *
+ *   You should have received a copy of the GNU Lesser General Public       *
+ *   License along with FreeCAD. If not, see                                *
+ *   <https://www.gnu.org/licenses/>.                                       *
+ *                                                                          *
+ ***************************************************************************/
+
+
+#ifndef LAUNCHERGUI_WORKBENCH_H
+#define LAUNCHERGUI_WORKBENCH_H
+
+#include <Gui/Workbench.h>
+#include <memory>
+
+namespace Gui {
+class MDIView;
+}
+
+namespace CleanStartGui
+{
+
+class Workbench: public Gui::StdWorkbench
+{
+    TYPESYSTEM_HEADER_WITH_OVERRIDE();  // NOLINT
+
+public:
+    Workbench() = default;
+
+    /** Run some actions when the workbench gets activated. */
+    void activated() override;
+
+    static void loadCleanStart();
+
+protected:
+    /** Defines the standard menus. */
+    Gui::MenuItem* setupMenuBar() const override;
+    /** Defines the standard toolbars. */
+    Gui::ToolBarItem* setupToolBars() const override;
+    /** Defines the standard command bars. */
+    Gui::ToolBarItem* setupCommandBars() const override;
+    /** Returns a DockWindowItems structure of dock windows this workbench. */
+    Gui::DockWindowItems* setupDockWindows() const override;
+
+};  // class Workbench
+
+}  // namespace CleanStartGui
+#endif  // LAUNCHERGUI_WORKBENCH_H

src/Mod/CleanStart/Init.py

@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# /**************************************************************************
+#                                                                           *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+#                                                                           *
+#    This file is part of FreeCAD.                                          *
+#                                                                           *
+#    FreeCAD is free software: you can redistribute it and/or modify it     *
+#    under the terms of the GNU Lesser General Public License as            *
+#    published by the Free Software Foundation, either version 2.1 of the   *
+#    License, or (at your option) any later version.                        *
+#                                                                           *
+#    FreeCAD 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       *
+#    Lesser General Public License for more details.                        *
+#                                                                           *
+#    You should have received a copy of the GNU Lesser General Public       *
+#    License along with FreeCAD. If not, see                                *
+#    <https://www.gnu.org/licenses/>.                                       *
+#                                                                           *
+# **************************************************************************/
+
+# Get the Parameter Group of this module
+ParGrp = App.ParamGet("System parameter:Modules").GetGroup("CleanStart")
+
+# Set the needed information
+ParGrp.SetString("WorkBenchName", "CleanStart")
+ParGrp.SetString("WorkBenchModule", "CleanStart.py")

src/Mod/CleanStart/InitGui.py

@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+# /**************************************************************************
+#                                                                           *
+#    Copyright (c) 2024 The FreeCAD Project Association AISBL               *
+#                                                                           *
+#    This file is part of FreeCAD.                                          *
+#                                                                           *
+#    FreeCAD is free software: you can redistribute it and/or modify it     *
+#    under the terms of the GNU Lesser General Public License as            *
+#    published by the Free Software Foundation, either version 2.1 of the   *
+#    License, or (at your option) any later version.                        *
+#                                                                           *
+#    FreeCAD 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       *
+#    Lesser General Public License for more details.                        *
+#                                                                           *
+#    You should have received a copy of the GNU Lesser General Public       *
+#    License along with FreeCAD. If not, see                                *
+#    <https://www.gnu.org/licenses/>.                                       *
+#                                                                           *
+# **************************************************************************/
+
+
+class CleanStartWorkbench(Workbench):
+    "CleanStartWorkbench workbench"
+
+    def __init__(self):
+        self.__class__.Icon = (
+                FreeCAD.getResourceDir() + "Mod/Start/Resources/icons/StartWorkbench.svg"
+        )
+        self.__class__.MenuText = "Start (new!)"
+        self.__class__.ToolTip = "Start workbench"
+
+    def Initialize(self):
+        import CleanStartGui
+
+    def Activated(self):
+        pass
+
+    def Deactivated(self):
+        pass
+
+    def ContextMenu(self, recipient):
+        pass
+
+    def GetClassName(self):
+        return "CleanStartGui::Workbench"
+
+
+Gui.addWorkbench(CleanStartWorkbench())

src/Mod/CleanStart/README.md

@@ -0,0 +1,53 @@
+## CleanStart Workbench
+
+This Workbench is intended to eventually replace (and be renamed to) Start. Its main reason for existing is to
+eliminate FreeCAD's dependency on QtWebEngine by redesigning Start to eliminate the HTML component.
+
+The long-term plan for this workbench is to migrate from Qt Widgets to QtQuick/QML with a C++ backend providing access
+to things like FreeCAD's Recent Files list. This switch will happen sometime after we no longer have to support building
+on Ubuntu 20.04 LTS, which still uses Qt 5.12. The cMake integration of QML and C++ together in a single project is
+greatly improved in Qt 5.15 and later.
+
+In the meantime the workbench is written in C++ so that the models can be re-used later, and only the UI itself will
+have to change.
+
+### Structure
+
+The main UI file for the Start screen is in `Gui/CleanStartView.cpp` -- that class is a `QScrollArea` that gets embedded
+into a new FreeCAD `MDIView`. Inside the scroll area are three regions:
+
+1. **New File**. A set of `QPushButtons` with embedded `QLayouts` displaying an image and two lines of text. Currently
+laid out manually in a `QGridLayout`, but eventually it would be nice to dynamically calculate that layout to allow the
+buttons to exist on a single line when there is enough space for them.
+2. **Recent Files**. One of two "File Card" regions, this shows a list of recent files. It uses the
+Model-View-Controller architecture for flexibility and re-usability. In that architecture, the data being displayed is
+called the "model", and the actual mechanism for doing the display is called the "view". Qt further differentiates
+between the overall view and the display of the individual items in the view. The items are rendered by a "delegate"
+when they are too complex to be displayed by the simple view (e.g. if you want images and text in a particular layout).
+    * The "model" in this case is `RecentFilesModel`, a simple read-only interface to 
+FreeCAD's preferences system, where it gets the list of recent files. That class is in`App/RecentFilesModel.*`. It is
+implemented using a set of User Roles, one for each piece of data about a file. Not all data is available for all files.
+For example, when given `const QModelIndex &index`, you can call `index.data(DisplayedFilesModelRoles::author)` to get
+the "author" metadata item of an `FCStd` file. See the `DisplayedFilesModelRoles` enumeration for possible values. These
+roles are also exposed to QML via their names.
+    * The View is a class derived from `QListView`, `Gui/FileCardView.*`, whose only function beyond the standard 
+`QListView` is to implement the "height for width" functionality, so the widget can properly resize based on the number
+of file cards and the screen width, laying them out in a grid. 
+    * The file cards are rendered using the `FileCardDelegate` class in `Gui/FileCardDelegate.*`. That class uses
+a simple `QVBoxLayout` to paint the icon, filename, and file size.
+3. **Examples**. Another "File Card" widget, using the same classes as Recent Files, but with a different model. In this
+case the model is `ExamplesModel` in `App/ExamplesModel.*`. It fetches a read-only list of files from the FreeCAD
+`resources/examples` directory and displays them.
+
+### UI Design
+
+This Workbench does the minimum amount of design customization, preferring to allow Stylesheet authors control over the
+display via the normal QSS mechanisms in Qt. There are three FreeCAD Parameters that control the spacing between the
+widgets and the size of the icons, all in the `BaseApp/Preferences/Mod/Start/` preferences group:
+* `FileCardSpacing` (default: 20). The space between and around the individual File Cards.
+* `FileThumbnailIconsSize` (default: 128). The size of the file thumbnail on the File Cards.
+* `NewFileIconSize` (default: 48). The size of the icons on each of the "new file" buttons.
+
+At present none of these are directly exposed to the user, and the new Start workbench does not have a preferences
+panel. The parameters are intended to be used by Preference Pack authors to assist in customization of FreeCAD themes.
+It is likely that this will be expanded once feedback from theme designers is received.