diff --git a/src/libtiled/mapreader.h b/src/libtiled/mapreader.h
index 8a8c169452..8ca2d41e40 100644
--- a/src/libtiled/mapreader.h
+++ b/src/libtiled/mapreader.h
@@ -42,7 +42,7 @@ class Map;
 
 namespace Internal {
 class MapReaderPrivate;
-}
+} // namespace Internal
 
 /**
  * A fast QXmlStreamReader based reader for the TMX and TSX formats.
diff --git a/src/libtiled/mapwriter.h b/src/libtiled/mapwriter.h
index 17cefc3bd3..4c94672ec4 100644
--- a/src/libtiled/mapwriter.h
+++ b/src/libtiled/mapwriter.h
@@ -45,7 +45,7 @@ class Tileset;
 
 namespace Internal {
 class MapWriterPrivate;
-}
+} // namespace Internal
 
 /**
  * A QXmlStreamWriter based writer for the TMX and TSX formats.
diff --git a/src/libtiled/templatemanager.h b/src/libtiled/templatemanager.h
index 997634989a..05acd01a64 100644
--- a/src/libtiled/templatemanager.h
+++ b/src/libtiled/templatemanager.h
@@ -69,4 +69,4 @@ inline ObjectTemplate *TemplateManager::findObjectTemplate(const QString &fileNa
     return mObjectTemplates.value(fileName);
 }
 
-} // namespace Tiled::Internal
+} // namespace Tiled
diff --git a/src/tiled/aboutdialog.cpp b/src/tiled/aboutdialog.cpp
index e703ca318b..9ca9e34578 100644
--- a/src/tiled/aboutdialog.cpp
+++ b/src/tiled/aboutdialog.cpp
@@ -30,7 +30,7 @@
 
 #include <cmath>
 
-using namespace Tiled::Internal;
+using namespace Tiled;
 
 AboutDialog::AboutDialog(QWidget *parent): QDialog(parent)
 {
diff --git a/src/tiled/aboutdialog.h b/src/tiled/aboutdialog.h
index 1f4490a66c..2f67db4968 100644
--- a/src/tiled/aboutdialog.h
+++ b/src/tiled/aboutdialog.h
@@ -25,7 +25,6 @@
 #include "ui_aboutdialog.h"
 
 namespace Tiled {
-namespace Internal {
 
 class AboutDialog : public QDialog, private Ui::AboutDialog
 {
@@ -38,5 +37,4 @@ private slots:
     void donate();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/abstractobjecttool.cpp b/src/tiled/abstractobjecttool.cpp
index 13e12985bf..a4430d03dd 100644
--- a/src/tiled/abstractobjecttool.cpp
+++ b/src/tiled/abstractobjecttool.cpp
@@ -48,7 +48,6 @@
 #include <QtMath>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 static bool isTileObject(MapObject *mapObject)
 {
@@ -175,13 +174,13 @@ void AbstractObjectTool::languageChanged()
 {
     mFlipHorizontal->setToolTip(tr("Flip Horizontally"));
     mFlipVertical->setToolTip(tr("Flip Vertically"));
-    mRotateLeft->setToolTip(QCoreApplication::translate("Tiled::Internal::StampActions", "Rotate Left"));
-    mRotateRight->setToolTip(QCoreApplication::translate("Tiled::Internal::StampActions", "Rotate Right"));
+    mRotateLeft->setToolTip(QCoreApplication::translate("Tiled::StampActions", "Rotate Left"));
+    mRotateRight->setToolTip(QCoreApplication::translate("Tiled::StampActions", "Rotate Right"));
 
-    mFlipHorizontal->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::Internal::StampActions", "X")));
-    mFlipVertical->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::Internal::StampActions", "Y")));
-    mRotateLeft->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::Internal::StampActions", "Shift+Z")));
-    mRotateRight->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::Internal::StampActions", "Z")));
+    mFlipHorizontal->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::StampActions", "X")));
+    mFlipVertical->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::StampActions", "Y")));
+    mRotateLeft->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::StampActions", "Shift+Z")));
+    mRotateRight->setShortcut(QKeySequence(QCoreApplication::translate("Tiled::StampActions", "Z")));
 }
 
 void AbstractObjectTool::populateToolBar(QToolBar *toolBar)
@@ -281,12 +280,12 @@ static QString saveObjectTemplate(const MapObject *mapObject)
     if (!mapObject->name().isEmpty())
         suggestedFileName += mapObject->name();
     else
-        suggestedFileName += QCoreApplication::translate("Tiled::Internal::MainWindow", "untitled");
+        suggestedFileName += QCoreApplication::translate("Tiled::MainWindow", "untitled");
     suggestedFileName += QLatin1String(".tx");
 
     QWidget *parent = DocumentManager::instance()->widget()->window();
     QString fileName = QFileDialog::getSaveFileName(parent,
-                                                    QCoreApplication::translate("Tiled::Internal::MainWindow", "Save Template"),
+                                                    QCoreApplication::translate("Tiled::MainWindow", "Save Template"),
                                                     suggestedFileName,
                                                     filter,
                                                     &selectedFilter);
@@ -300,7 +299,7 @@ static QString saveObjectTemplate(const MapObject *mapObject)
     objectTemplate.setObject(mapObject);
 
     if (!format->write(&objectTemplate, fileName)) {
-        QMessageBox::critical(nullptr, QCoreApplication::translate("Tiled::Internal::MainWindow", "Error Saving Template"),
+        QMessageBox::critical(nullptr, QCoreApplication::translate("Tiled::MainWindow", "Error Saving Template"),
                               format->errorString());
         return QString();
     }
diff --git a/src/tiled/abstractobjecttool.h b/src/tiled/abstractobjecttool.h
index cfe9057350..e45a3c2715 100644
--- a/src/tiled/abstractobjecttool.h
+++ b/src/tiled/abstractobjecttool.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class MapObject;
 class ObjectGroup;
 
-namespace Internal {
-
 class MapObjectItem;
 
 /**
@@ -106,5 +104,4 @@ private slots:
     QAction *mRotateRight;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/abstracttilefilltool.cpp b/src/tiled/abstracttilefilltool.cpp
index da53254d9a..84c4985dc6 100644
--- a/src/tiled/abstracttilefilltool.cpp
+++ b/src/tiled/abstracttilefilltool.cpp
@@ -28,7 +28,6 @@
 #include <QAction>
 
 using namespace Tiled;
-using namespace Internal;
 
 AbstractTileFillTool::AbstractTileFillTool(const QString &name,
                                            const QIcon &icon,
diff --git a/src/tiled/abstracttilefilltool.h b/src/tiled/abstracttilefilltool.h
index ca5fad4a5e..a31111b319 100644
--- a/src/tiled/abstracttilefilltool.h
+++ b/src/tiled/abstracttilefilltool.h
@@ -31,8 +31,6 @@ namespace Tiled {
 
 class WangSet;
 
-namespace Internal {
-
 class MapDocument;
 class StampActions;
 class WangFiller;
@@ -141,5 +139,4 @@ inline bool AbstractTileFillTool::isCapturing() const
     return mCaptureStampHelper.isActive();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/abstracttileselectiontool.cpp b/src/tiled/abstracttileselectiontool.cpp
index 724252efd9..23aaaa3da7 100644
--- a/src/tiled/abstracttileselectiontool.cpp
+++ b/src/tiled/abstracttileselectiontool.cpp
@@ -30,7 +30,6 @@
 #include <QToolBar>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AbstractTileSelectionTool::AbstractTileSelectionTool(const QString &name,
                                                      const QIcon &icon,
diff --git a/src/tiled/abstracttileselectiontool.h b/src/tiled/abstracttileselectiontool.h
index 57e4561d35..5901a01bc1 100644
--- a/src/tiled/abstracttileselectiontool.h
+++ b/src/tiled/abstracttileselectiontool.h
@@ -27,7 +27,6 @@ class QAction;
 class QActionGroup;
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -78,5 +77,4 @@ class AbstractTileSelectionTool : public AbstractTileTool
     QActionGroup *mActionGroup;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/abstracttiletool.cpp b/src/tiled/abstracttiletool.cpp
index 0bf707fc14..4fd2459846 100644
--- a/src/tiled/abstracttiletool.cpp
+++ b/src/tiled/abstracttiletool.cpp
@@ -32,7 +32,6 @@
 #include <QtMath>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AbstractTileTool::AbstractTileTool(const QString &name,
                                    const QIcon &icon,
diff --git a/src/tiled/abstracttiletool.h b/src/tiled/abstracttiletool.h
index e27c69f23f..5e9eae35da 100644
--- a/src/tiled/abstracttiletool.h
+++ b/src/tiled/abstracttiletool.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class TileLayer;
 
-namespace Internal {
-
 class BrushItem;
 class MapDocument;
 class TileStamp;
@@ -130,5 +128,4 @@ class AbstractTileTool : public AbstractTool
     bool mBrushVisible;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/abstracttool.cpp b/src/tiled/abstracttool.cpp
index 6441980532..71f70384c0 100644
--- a/src/tiled/abstracttool.cpp
+++ b/src/tiled/abstracttool.cpp
@@ -27,7 +27,6 @@
 #include <QKeyEvent>
 
 namespace Tiled {
-namespace Internal {
 
 AbstractTool::AbstractTool(const QString &name, const QIcon &icon,
                            const QKeySequence &shortcut, QObject *parent)
@@ -127,5 +126,4 @@ Layer *AbstractTool::currentLayer() const
     return mMapDocument ? mMapDocument->currentLayer() : nullptr;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/abstracttool.h b/src/tiled/abstracttool.h
index 90be717c86..56576cbc69 100644
--- a/src/tiled/abstracttool.h
+++ b/src/tiled/abstracttool.h
@@ -39,8 +39,6 @@ class Layer;
 class Tile;
 class ObjectTemplate;
 
-namespace Internal {
-
 class MapDocument;
 class MapScene;
 class ToolManager;
@@ -260,7 +258,6 @@ inline ToolManager *AbstractTool::toolManager() const
     return mToolManager;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::AbstractTool*)
+Q_DECLARE_METATYPE(Tiled::AbstractTool*)
diff --git a/src/tiled/actionmanager.cpp b/src/tiled/actionmanager.cpp
index 9227a445d8..e627b90bd7 100644
--- a/src/tiled/actionmanager.cpp
+++ b/src/tiled/actionmanager.cpp
@@ -23,7 +23,6 @@
 #include <QHash>
 
 namespace Tiled {
-namespace Internal {
 
 class ActionManagerPrivate
 {
@@ -65,5 +64,4 @@ QAction *ActionManager::findAction(Id id)
     return d->mIdToAction.value(id);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/actionmanager.h b/src/tiled/actionmanager.h
index 3064d5cc58..b94a841275 100644
--- a/src/tiled/actionmanager.h
+++ b/src/tiled/actionmanager.h
@@ -27,7 +27,6 @@
 class QAction;
 
 namespace Tiled {
-namespace Internal {
 
 class MainWindow;
 
@@ -51,8 +50,7 @@ class ActionManager : public QObject
     explicit ActionManager(QObject *parent = nullptr);
     ~ActionManager();
 
-    friend class Tiled::Internal::MainWindow;   // creation
+    friend class Tiled::MainWindow;   // creation
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addpropertydialog.cpp b/src/tiled/addpropertydialog.cpp
index 0efc9fcec3..2da57a379a 100644
--- a/src/tiled/addpropertydialog.cpp
+++ b/src/tiled/addpropertydialog.cpp
@@ -30,7 +30,6 @@
 #include <QSettings>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 static const char * const TYPE_KEY = "AddPropertyDialog/PropertyType";
 
diff --git a/src/tiled/addremovelayer.cpp b/src/tiled/addremovelayer.cpp
index 7511e5897a..20d1a7cbdd 100644
--- a/src/tiled/addremovelayer.cpp
+++ b/src/tiled/addremovelayer.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 AddRemoveLayer::AddRemoveLayer(MapDocument *mapDocument,
                                int index,
@@ -83,5 +82,4 @@ RemoveLayer::RemoveLayer(MapDocument *mapDocument,
     setText(QCoreApplication::translate("Undo Commands", "Remove Layer"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremovelayer.h b/src/tiled/addremovelayer.h
index 41e60e0b66..b8e2453ac5 100644
--- a/src/tiled/addremovelayer.h
+++ b/src/tiled/addremovelayer.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class GroupLayer;
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -98,5 +96,4 @@ class RemoveLayer : public AddRemoveLayer
     { removeLayer(); }
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremovemapobject.cpp b/src/tiled/addremovemapobject.cpp
index 22a59c8d9c..a53835c71c 100644
--- a/src/tiled/addremovemapobject.cpp
+++ b/src/tiled/addremovemapobject.cpp
@@ -31,7 +31,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AddRemoveMapObjects::AddRemoveMapObjects(MapDocument *mapDocument,
                                          const QVector<Entry> &entries,
diff --git a/src/tiled/addremovemapobject.h b/src/tiled/addremovemapobject.h
index 6c632b8069..57e7298234 100644
--- a/src/tiled/addremovemapobject.h
+++ b/src/tiled/addremovemapobject.h
@@ -28,8 +28,6 @@ namespace Tiled {
 class MapObject;
 class ObjectGroup;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -103,5 +101,4 @@ class RemoveMapObjects : public AddRemoveMapObjects
     void redo() override;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremoveterrain.cpp b/src/tiled/addremoveterrain.cpp
index 145858a0f2..9b09ea3049 100644
--- a/src/tiled/addremoveterrain.cpp
+++ b/src/tiled/addremoveterrain.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AddRemoveTerrain::AddRemoveTerrain(TilesetDocument *tilesetDocument,
                                    int index,
diff --git a/src/tiled/addremoveterrain.h b/src/tiled/addremoveterrain.h
index a4ddfec480..de91c6f3aa 100644
--- a/src/tiled/addremoveterrain.h
+++ b/src/tiled/addremoveterrain.h
@@ -27,8 +27,6 @@ namespace Tiled {
 class Terrain;
 class Tileset;
 
-namespace Internal {
-
 class TilesetDocument;
 
 /**
@@ -78,5 +76,4 @@ class RemoveTerrain : public AddRemoveTerrain
     void redo() override { removeTerrain(); }
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremovetiles.cpp b/src/tiled/addremovetiles.cpp
index 9e2dd02f51..1db3158a54 100644
--- a/src/tiled/addremovetiles.cpp
+++ b/src/tiled/addremovetiles.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 AddRemoveTiles::AddRemoveTiles(TilesetDocument *tilesetDocument,
                                const QList<Tile *> &tiles,
@@ -71,5 +70,4 @@ RemoveTiles::RemoveTiles(TilesetDocument *tilesetDocument,
     setText(QCoreApplication::translate("Undo Commands", "Remove Tiles"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremovetiles.h b/src/tiled/addremovetiles.h
index 4773b2a2e9..6026627bca 100644
--- a/src/tiled/addremovetiles.h
+++ b/src/tiled/addremovetiles.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Tile;
 
-namespace Internal {
-
 class TilesetDocument;
 
 /**
@@ -84,5 +82,4 @@ class RemoveTiles : public AddRemoveTiles
     { removeTiles(); }
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremovetileset.cpp b/src/tiled/addremovetileset.cpp
index c945739180..7cc9fdbf02 100644
--- a/src/tiled/addremovetileset.cpp
+++ b/src/tiled/addremovetileset.cpp
@@ -24,7 +24,6 @@
 #include "mapdocument.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AddRemoveTileset::AddRemoveTileset(MapDocument *mapDocument,
                                    int index,
diff --git a/src/tiled/addremovetileset.h b/src/tiled/addremovetileset.h
index 608e8abeb4..b4dd72237d 100644
--- a/src/tiled/addremovetileset.h
+++ b/src/tiled/addremovetileset.h
@@ -27,7 +27,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -86,5 +85,4 @@ class RemoveTileset : public AddRemoveTileset
     { removeTileset(); }
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/addremovewangset.cpp b/src/tiled/addremovewangset.cpp
index d9a190a789..8c1d69694a 100644
--- a/src/tiled/addremovewangset.cpp
+++ b/src/tiled/addremovewangset.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Internal;
 
 AddRemoveWangSet::AddRemoveWangSet(TilesetDocument *tilesetDocument,
                                    int index,
diff --git a/src/tiled/addremovewangset.h b/src/tiled/addremovewangset.h
index e8bca08591..cbb2c04801 100644
--- a/src/tiled/addremovewangset.h
+++ b/src/tiled/addremovewangset.h
@@ -26,9 +26,6 @@ namespace Tiled {
 
 class WangSet;
 class Tileset;
-
-namespace Internal {
-
 class TilesetDocument;
 
 class AddRemoveWangSet : public QUndoCommand
@@ -67,5 +64,4 @@ class RemoveWangSet : public AddRemoveWangSet
     void redo() override { removeWangSet(); }
 };
 
-} // namespace internal
-} // namespace tiled
+} // namespace Tiled
diff --git a/src/tiled/adjusttileindexes.cpp b/src/tiled/adjusttileindexes.cpp
index 1fce6a7184..82fcf0c54f 100644
--- a/src/tiled/adjusttileindexes.cpp
+++ b/src/tiled/adjusttileindexes.cpp
@@ -42,7 +42,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 AdjustTileIndexes::AdjustTileIndexes(MapDocument *mapDocument,
                                      const Tileset &tileset)
@@ -316,5 +315,4 @@ AdjustTileMetaData::AdjustTileMetaData(TilesetDocument *tilesetDocument)
         new ChangeTileTerrain(tilesetDocument, terrainChanges, this);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/adjusttileindexes.h b/src/tiled/adjusttileindexes.h
index 9373045cf1..abf80104cd 100644
--- a/src/tiled/adjusttileindexes.h
+++ b/src/tiled/adjusttileindexes.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Tileset;
 
-namespace Internal {
-
 class MapDocument;
 class TilesetDocument;
 
@@ -51,5 +49,4 @@ class AdjustTileMetaData : public QUndoCommand
     AdjustTileMetaData(TilesetDocument *tilesetDocument);
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/automapper.cpp b/src/tiled/automapper.cpp
index f9e764d59c..77796cbe9e 100644
--- a/src/tiled/automapper.cpp
+++ b/src/tiled/automapper.cpp
@@ -41,7 +41,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 /*
  * About the order of the methods in this file.
diff --git a/src/tiled/automapper.h b/src/tiled/automapper.h
index dcf6daeb59..993803d751 100644
--- a/src/tiled/automapper.h
+++ b/src/tiled/automapper.h
@@ -37,8 +37,6 @@ class MapObject;
 class ObjectGroup;
 class TileLayer;
 
-namespace Internal {
-
 class MapDocument;
 
 struct InputLayer
@@ -374,5 +372,4 @@ class AutoMapper : public QObject
     QString mWarning;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/automapperwrapper.cpp b/src/tiled/automapperwrapper.cpp
index 767f9120b6..f579f4333b 100644
--- a/src/tiled/automapperwrapper.cpp
+++ b/src/tiled/automapperwrapper.cpp
@@ -28,7 +28,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AutoMapperWrapper::AutoMapperWrapper(MapDocument *mapDocument,
                                      QVector<AutoMapper*> autoMapper,
diff --git a/src/tiled/automapperwrapper.h b/src/tiled/automapperwrapper.h
index 6311ab6168..297d98e208 100644
--- a/src/tiled/automapperwrapper.h
+++ b/src/tiled/automapperwrapper.h
@@ -27,7 +27,6 @@
 
 namespace Tiled {
 
-namespace Internal {
 
 class MapDocument;
 
@@ -56,5 +55,4 @@ class AutoMapperWrapper : public QUndoCommand
     QVector<TileLayer*> mLayersBefore;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/automappingmanager.cpp b/src/tiled/automappingmanager.cpp
index 55882ab5f1..b26fc4c8c6 100644
--- a/src/tiled/automappingmanager.cpp
+++ b/src/tiled/automappingmanager.cpp
@@ -36,7 +36,6 @@
 #include <memory>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 AutomappingManager::AutomappingManager(QObject *parent)
     : QObject(parent)
diff --git a/src/tiled/automappingmanager.h b/src/tiled/automappingmanager.h
index 41ff2fc0c5..6e454437fb 100644
--- a/src/tiled/automappingmanager.h
+++ b/src/tiled/automappingmanager.h
@@ -30,8 +30,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class AutoMapper;
 class MapDocument;
 
@@ -142,5 +140,4 @@ private slots:
     QString rulesFileName() const;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/automappingutils.cpp b/src/tiled/automappingutils.cpp
index 5723a728bd..425ac13f0c 100644
--- a/src/tiled/automappingutils.cpp
+++ b/src/tiled/automappingutils.cpp
@@ -30,7 +30,6 @@
 #include <QUndoStack>
 
 namespace Tiled {
-namespace Internal {
 
 void eraseRegionObjectGroup(MapDocument *mapDocument,
                             ObjectGroup *layer,
@@ -96,5 +95,4 @@ const QList<MapObject*> objectsInRegion(const ObjectGroup *layer,
     return ret;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/automappingutils.h b/src/tiled/automappingutils.h
index f8c396763c..5bac0363f3 100644
--- a/src/tiled/automappingutils.h
+++ b/src/tiled/automappingutils.h
@@ -27,8 +27,6 @@ namespace Tiled {
 class MapObject;
 class ObjectGroup;
 
-namespace Internal {
-
 class MapDocument;
 
 const QList<MapObject*> objectsInRegion(const ObjectGroup *layer,
@@ -40,5 +38,4 @@ void eraseRegionObjectGroup(MapDocument *mapDocument,
 
 QRegion tileRegionOfObjectGroup(const ObjectGroup *layer);
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/brokenlinks.cpp b/src/tiled/brokenlinks.cpp
index a1b525dce1..29c31170c1 100644
--- a/src/tiled/brokenlinks.cpp
+++ b/src/tiled/brokenlinks.cpp
@@ -54,7 +54,6 @@
 #include <algorithm>
 
 namespace Tiled {
-namespace Internal {
 
 QString BrokenLink::filePath() const
 {
@@ -484,15 +483,15 @@ void BrokenLinksWidget::selectionChanged()
         const BrokenLink &link = mBrokenLinksModel->brokenLink(firstIndex.row());
 
         switch (link.type) {
-        case Tiled::Internal::MapTilesetReference:
-        case Tiled::Internal::ObjectTemplateReference:
+        case MapTilesetReference:
+        case ObjectTemplateReference:
             mLocateButton->setText(tr("Locate File..."));
             break;
-        case Tiled::Internal::ObjectTemplateTilesetReference:
+        case ObjectTemplateTilesetReference:
             mLocateButton->setText(tr("Open Template..."));
             break;
-        case Tiled::Internal::TilesetTileImageSource:
-        case Tiled::Internal::TilesetImageSource:
+        case TilesetTileImageSource:
+        case TilesetImageSource:
             if (isTileset)
                 mLocateButton->setText(tr("Locate File..."));
             else
@@ -673,7 +672,7 @@ bool BrokenLinksWidget::tryFixLink(const BrokenLink &link, const QString &newFil
         SharedTileset newTileset = TilesetManager::instance()->findTileset(newFilePath);
         if (!newTileset || newTileset->status() == LoadingError) {
             QString error;
-            newTileset = Tiled::readTileset(newFilePath, &error);
+            newTileset = readTileset(newFilePath, &error);
 
             if (!newTileset) {
                 QMessageBox::critical(window(), tr("Error Reading Tileset"), error);
@@ -708,5 +707,4 @@ bool BrokenLinksWidget::tryFixLink(const BrokenLink &link, const QString &newFil
     return true;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/brokenlinks.h b/src/tiled/brokenlinks.h
index 6794bc558c..fc8488c554 100644
--- a/src/tiled/brokenlinks.h
+++ b/src/tiled/brokenlinks.h
@@ -38,8 +38,6 @@ class Tile;
 class Tileset;
 class ObjectTemplate;
 
-namespace Internal {
-
 class Document;
 class TilesetDocument;
 
@@ -153,5 +151,4 @@ private slots:
     QAbstractButton *mLocateButton;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/brushitem.cpp b/src/tiled/brushitem.cpp
index 83272028ac..27e3dc4188 100644
--- a/src/tiled/brushitem.cpp
+++ b/src/tiled/brushitem.cpp
@@ -33,7 +33,6 @@
 #include <QUndoStack>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 BrushItem::BrushItem():
     mMapDocument(nullptr)
diff --git a/src/tiled/brushitem.h b/src/tiled/brushitem.h
index 0cd39cc893..e05e7c57c0 100644
--- a/src/tiled/brushitem.h
+++ b/src/tiled/brushitem.h
@@ -27,7 +27,6 @@
 #include <QGraphicsItem>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -102,5 +101,4 @@ inline const QRegion &BrushItem::tileRegion() const
     return mRegion;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/bucketfilltool.cpp b/src/tiled/bucketfilltool.cpp
index 7d63842c21..4040ba49b2 100644
--- a/src/tiled/bucketfilltool.cpp
+++ b/src/tiled/bucketfilltool.cpp
@@ -38,7 +38,6 @@
 #include <memory>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 BucketFillTool::BucketFillTool(QObject *parent)
     : AbstractTileFillTool(tr("Bucket Fill Tool"),
diff --git a/src/tiled/bucketfilltool.h b/src/tiled/bucketfilltool.h
index 04b5138618..64ee324720 100644
--- a/src/tiled/bucketfilltool.h
+++ b/src/tiled/bucketfilltool.h
@@ -30,8 +30,6 @@ namespace Tiled {
 
 class WangSet;
 
-namespace Internal {
-
 class MapDocument;
 class StampActions;
 class WangFiller;
@@ -77,5 +75,4 @@ private slots:
     void makeConnections();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/capturestamphelper.cpp b/src/tiled/capturestamphelper.cpp
index d0cc02c10c..e013774760 100644
--- a/src/tiled/capturestamphelper.cpp
+++ b/src/tiled/capturestamphelper.cpp
@@ -27,7 +27,6 @@
 #include <memory>
 
 namespace Tiled {
-namespace Internal {
 
 CaptureStampHelper::CaptureStampHelper()
     : mActive(false)
@@ -108,5 +107,4 @@ QRect CaptureStampHelper::capturedArea(QPoint tilePosition) const
     return captured;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/capturestamphelper.h b/src/tiled/capturestamphelper.h
index 568ca0e994..ca49da761c 100644
--- a/src/tiled/capturestamphelper.h
+++ b/src/tiled/capturestamphelper.h
@@ -26,7 +26,6 @@
 #include <QRect>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -48,7 +47,6 @@ class CaptureStampHelper
     bool mActive;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
 #endif // CAPTURESTAMPHELPER_H
diff --git a/src/tiled/changeimagelayerposition.cpp b/src/tiled/changeimagelayerposition.cpp
index 210a4f5cd4..d18210b5e4 100644
--- a/src/tiled/changeimagelayerposition.cpp
+++ b/src/tiled/changeimagelayerposition.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeImageLayerPosition::ChangeImageLayerPosition(
         MapDocument *mapDocument,
diff --git a/src/tiled/changeimagelayerposition.h b/src/tiled/changeimagelayerposition.h
index d929b22917..cc8527d82d 100644
--- a/src/tiled/changeimagelayerposition.h
+++ b/src/tiled/changeimagelayerposition.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class ImageLayer;
 
-namespace Internal {
-
 class MapDocument;
 
 class ChangeImageLayerPosition : public QUndoCommand
@@ -55,5 +53,4 @@ class ChangeImageLayerPosition : public QUndoCommand
     const QPoint mRedoPos;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changeimagelayerproperties.cpp b/src/tiled/changeimagelayerproperties.cpp
index d97ac99c9c..d9ca3ca871 100644
--- a/src/tiled/changeimagelayerproperties.cpp
+++ b/src/tiled/changeimagelayerproperties.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeImageLayerProperties::ChangeImageLayerProperties(
         MapDocument *mapDocument,
diff --git a/src/tiled/changeimagelayerproperties.h b/src/tiled/changeimagelayerproperties.h
index 134fcb1418..394545a4fb 100644
--- a/src/tiled/changeimagelayerproperties.h
+++ b/src/tiled/changeimagelayerproperties.h
@@ -30,8 +30,6 @@ namespace Tiled {
 
 class ImageLayer;
 
-namespace Internal {
-
 class MapDocument;
 
 class ChangeImageLayerProperties : public QUndoCommand
@@ -62,5 +60,4 @@ class ChangeImageLayerProperties : public QUndoCommand
     const QUrl mRedoSource;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changelayer.cpp b/src/tiled/changelayer.cpp
index 6a88e4270d..ec554867f7 100644
--- a/src/tiled/changelayer.cpp
+++ b/src/tiled/changelayer.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 SetLayerVisible::SetLayerVisible(MapDocument *mapDocument,
                                  Layer *layer,
@@ -124,5 +123,4 @@ void SetLayerOffset::setOffset(const QPointF &offset)
 }
 
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changelayer.h b/src/tiled/changelayer.h
index aeea70d1df..4f8f4fa849 100644
--- a/src/tiled/changelayer.h
+++ b/src/tiled/changelayer.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -127,5 +125,4 @@ class SetLayerOffset : public QUndoCommand
     QPointF mNewOffset;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changemapobject.cpp b/src/tiled/changemapobject.cpp
index 9bb7589376..0cf4b596b0 100644
--- a/src/tiled/changemapobject.cpp
+++ b/src/tiled/changemapobject.cpp
@@ -29,7 +29,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeMapObject::ChangeMapObject(MapDocument *mapDocument,
                                  MapObject *mapObject,
diff --git a/src/tiled/changemapobject.h b/src/tiled/changemapobject.h
index d108a77035..1acb373af0 100644
--- a/src/tiled/changemapobject.h
+++ b/src/tiled/changemapobject.h
@@ -32,8 +32,6 @@ class MapObject;
 class ObjectTemplate;
 class Tile;
 
-namespace Internal {
-
 class MapDocument;
 class MapObjectModel;
 
@@ -175,5 +173,4 @@ class ReplaceObjectsWithTemplate : public QUndoCommand
     ObjectTemplate *mObjectTemplate;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changemapobjectsorder.cpp b/src/tiled/changemapobjectsorder.cpp
index 399e18dfc1..95d6b09fe0 100644
--- a/src/tiled/changemapobjectsorder.cpp
+++ b/src/tiled/changemapobjectsorder.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeMapObjectsOrder::ChangeMapObjectsOrder(MapDocument *mapDocument,
                                              ObjectGroup *objectGroup,
diff --git a/src/tiled/changemapobjectsorder.h b/src/tiled/changemapobjectsorder.h
index 791f0e3812..44a3c3a4f0 100644
--- a/src/tiled/changemapobjectsorder.h
+++ b/src/tiled/changemapobjectsorder.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class ObjectGroup;
 
-namespace Internal {
-
 class MapDocument;
 
 class ChangeMapObjectsOrder : public QUndoCommand
@@ -51,5 +49,4 @@ class ChangeMapObjectsOrder : public QUndoCommand
     int mCount;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changemapproperty.cpp b/src/tiled/changemapproperty.cpp
index 65a100ee09..85a06ce195 100644
--- a/src/tiled/changemapproperty.cpp
+++ b/src/tiled/changemapproperty.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeMapProperty::ChangeMapProperty(MapDocument *mapDocument,
                                      ChangeMapProperty::Property property,
diff --git a/src/tiled/changemapproperty.h b/src/tiled/changemapproperty.h
index 3f3c18557b..84e3bcbd6b 100644
--- a/src/tiled/changemapproperty.h
+++ b/src/tiled/changemapproperty.h
@@ -26,7 +26,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -123,5 +122,4 @@ class ChangeMapProperty : public QUndoCommand
     };
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changeobjectgroupproperties.cpp b/src/tiled/changeobjectgroupproperties.cpp
index 7a344819a5..1769850878 100644
--- a/src/tiled/changeobjectgroupproperties.cpp
+++ b/src/tiled/changeobjectgroupproperties.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeObjectGroupProperties::ChangeObjectGroupProperties(
         MapDocument *mapDocument,
diff --git a/src/tiled/changeobjectgroupproperties.h b/src/tiled/changeobjectgroupproperties.h
index 15af683ee2..f65165b83c 100644
--- a/src/tiled/changeobjectgroupproperties.h
+++ b/src/tiled/changeobjectgroupproperties.h
@@ -27,7 +27,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -58,5 +57,4 @@ class ChangeObjectGroupProperties : public QUndoCommand
     ObjectGroup::DrawOrder mRedoDrawOrder;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changepolygon.cpp b/src/tiled/changepolygon.cpp
index c724a627f9..1f3758e40b 100644
--- a/src/tiled/changepolygon.cpp
+++ b/src/tiled/changepolygon.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangePolygon::ChangePolygon(MapDocument *mapDocument,
                              MapObject *mapObject,
diff --git a/src/tiled/changepolygon.h b/src/tiled/changepolygon.h
index 79ec997587..b4e83e70b7 100644
--- a/src/tiled/changepolygon.h
+++ b/src/tiled/changepolygon.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class MapObject;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -104,5 +102,4 @@ class SplitPolyline : public QUndoCommand
     bool mOwnsSecondPolyline;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changeproperties.cpp b/src/tiled/changeproperties.cpp
index 62bc6a4d4f..95215da5e7 100644
--- a/src/tiled/changeproperties.cpp
+++ b/src/tiled/changeproperties.cpp
@@ -25,7 +25,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ChangeProperties::ChangeProperties(Document *document,
                                    const QString &kind,
diff --git a/src/tiled/changeproperties.h b/src/tiled/changeproperties.h
index 7efe26fa1a..d60fc70749 100644
--- a/src/tiled/changeproperties.h
+++ b/src/tiled/changeproperties.h
@@ -27,7 +27,6 @@
 #include <QVector>
 
 namespace Tiled {
-namespace Internal {
 
 class Document;
 
@@ -134,5 +133,4 @@ class RenameProperty : public QUndoCommand
                    const QString &newName);
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changeselectedarea.cpp b/src/tiled/changeselectedarea.cpp
index 7b8d19ceef..56d8cf6774 100644
--- a/src/tiled/changeselectedarea.cpp
+++ b/src/tiled/changeselectedarea.cpp
@@ -24,7 +24,7 @@
 
 #include <QCoreApplication>
 
-using namespace Tiled::Internal;
+using namespace Tiled;
 
 ChangeSelectedArea::ChangeSelectedArea(MapDocument *mapDocument,
                                        const QRegion &newSelection,
diff --git a/src/tiled/changeselectedarea.h b/src/tiled/changeselectedarea.h
index 536e86afee..e89c1b2f26 100644
--- a/src/tiled/changeselectedarea.h
+++ b/src/tiled/changeselectedarea.h
@@ -24,7 +24,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -49,5 +48,4 @@ class ChangeSelectedArea: public QUndoCommand
     QRegion mSelection;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetile.cpp b/src/tiled/changetile.cpp
index 5bac9d7ac5..c8e54f3858 100644
--- a/src/tiled/changetile.cpp
+++ b/src/tiled/changetile.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ChangeTileType::ChangeTileType(TilesetDocument *tilesetDocument,
                                const QList<Tile *> &tiles,
@@ -49,5 +48,4 @@ void ChangeTileType::swap()
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetile.h b/src/tiled/changetile.h
index 9df2f7da43..c1d32ce6e1 100644
--- a/src/tiled/changetile.h
+++ b/src/tiled/changetile.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class Tile;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeTileType : public QUndoCommand
@@ -52,5 +50,4 @@ class ChangeTileType : public QUndoCommand
     QVector<QString> mTypes;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileanimation.cpp b/src/tiled/changetileanimation.cpp
index 4a91c423fc..2905c00af8 100644
--- a/src/tiled/changetileanimation.cpp
+++ b/src/tiled/changetileanimation.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ChangeTileAnimation::ChangeTileAnimation(TilesetDocument *document,
                                          Tile *tile,
@@ -51,5 +50,4 @@ void ChangeTileAnimation::swap()
     emit mTilesetDocument->tileAnimationChanged(mTile);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileanimation.h b/src/tiled/changetileanimation.h
index c1f3486741..df316f12a4 100644
--- a/src/tiled/changetileanimation.h
+++ b/src/tiled/changetileanimation.h
@@ -25,7 +25,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetDocument;
 
@@ -48,5 +47,4 @@ class ChangeTileAnimation : public QUndoCommand
     QVector<Frame> mFrames;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileimagesource.cpp b/src/tiled/changetileimagesource.cpp
index c361b53173..32666b18d6 100644
--- a/src/tiled/changetileimagesource.cpp
+++ b/src/tiled/changetileimagesource.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ChangeTileImageSource::ChangeTileImageSource(TilesetDocument *tilesetDocument,
                                              Tile *tile,
@@ -49,5 +48,4 @@ void ChangeTileImageSource::apply(const QUrl &imageSource)
                                    imageSource);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileimagesource.h b/src/tiled/changetileimagesource.h
index dec3f8ab95..b5316c7a4d 100644
--- a/src/tiled/changetileimagesource.h
+++ b/src/tiled/changetileimagesource.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class Tile;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeTileImageSource : public QUndoCommand
@@ -50,5 +48,4 @@ class ChangeTileImageSource : public QUndoCommand
     QUrl mNewImageSource;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileobjectgroup.cpp b/src/tiled/changetileobjectgroup.cpp
index 64980508e9..3cb5cab5ec 100644
--- a/src/tiled/changetileobjectgroup.cpp
+++ b/src/tiled/changetileobjectgroup.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ChangeTileObjectGroup::ChangeTileObjectGroup(TilesetDocument *tilesetDocument,
                                              Tile *tile,
@@ -48,5 +47,4 @@ void ChangeTileObjectGroup::swap()
     emit mTilesetDocument->tileObjectGroupChanged(mTile);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileobjectgroup.h b/src/tiled/changetileobjectgroup.h
index 37624e7a48..69db696064 100644
--- a/src/tiled/changetileobjectgroup.h
+++ b/src/tiled/changetileobjectgroup.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class ObjectGroup;
 class Tile;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeTileObjectGroup : public QUndoCommand
@@ -56,5 +54,4 @@ class ChangeTileObjectGroup : public QUndoCommand
     std::unique_ptr<ObjectGroup> mObjectGroup;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileprobability.cpp b/src/tiled/changetileprobability.cpp
index cbf5278204..dd2f8bbdc6 100644
--- a/src/tiled/changetileprobability.cpp
+++ b/src/tiled/changetileprobability.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ChangeTileProbability::ChangeTileProbability(TilesetDocument *tilesetDocument,
                                              const QList<Tile*>& tiles,
@@ -66,6 +65,5 @@ void ChangeTileProbability::swap()
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
 
diff --git a/src/tiled/changetileprobability.h b/src/tiled/changetileprobability.h
index d389de9add..8da59938b7 100644
--- a/src/tiled/changetileprobability.h
+++ b/src/tiled/changetileprobability.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Tile;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeTileProbability : public QUndoCommand
@@ -53,5 +51,4 @@ class ChangeTileProbability : public QUndoCommand
     QList<qreal> mProbabilities;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileterrain.cpp b/src/tiled/changetileterrain.cpp
index 571891f0b1..02e63d6533 100644
--- a/src/tiled/changetileterrain.cpp
+++ b/src/tiled/changetileterrain.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ChangeTileTerrain::ChangeTileTerrain()
     : mTilesetDocument(nullptr)
@@ -140,5 +139,4 @@ void ChangeTileTerrain::initText()
                                         "Change Tile Terrain"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetileterrain.h b/src/tiled/changetileterrain.h
index e99f338e92..8d4ca7a94a 100644
--- a/src/tiled/changetileterrain.h
+++ b/src/tiled/changetileterrain.h
@@ -30,8 +30,6 @@ namespace Tiled {
 class Tile;
 class Tileset;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeTileTerrain : public QUndoCommand
@@ -81,5 +79,4 @@ class ChangeTileTerrain : public QUndoCommand
     bool mMergeable;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changetilewangid.cpp b/src/tiled/changetilewangid.cpp
index 8fb406042b..89930be954 100644
--- a/src/tiled/changetilewangid.cpp
+++ b/src/tiled/changetilewangid.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Internal;
 
 ChangeTileWangId::ChangeTileWangId()
     : mTilesetDocument(nullptr)
diff --git a/src/tiled/changetilewangid.h b/src/tiled/changetilewangid.h
index 8b5236ea77..2b51479e74 100644
--- a/src/tiled/changetilewangid.h
+++ b/src/tiled/changetilewangid.h
@@ -26,7 +26,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetDocument;
 
@@ -73,5 +72,4 @@ class ChangeTileWangId : public QUndoCommand
     bool mMergeable;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changewangcolordata.cpp b/src/tiled/changewangcolordata.cpp
index aceee3465e..cc73013f68 100644
--- a/src/tiled/changewangcolordata.cpp
+++ b/src/tiled/changewangcolordata.cpp
@@ -24,7 +24,6 @@
 #include "tilesetdocument.h"
 
 using namespace Tiled;
-using namespace Internal;
 
 ChangeWangColorName::ChangeWangColorName(TilesetDocument *tilesetDocument,
                                          WangColor *wangColor,
diff --git a/src/tiled/changewangcolordata.h b/src/tiled/changewangcolordata.h
index 2b13d802a6..4b62c82a59 100644
--- a/src/tiled/changewangcolordata.h
+++ b/src/tiled/changewangcolordata.h
@@ -28,8 +28,6 @@ namespace Tiled {
 
 class WangColor;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeWangColorName : public QUndoCommand
@@ -101,5 +99,4 @@ class ChangeWangColorProbability : public QUndoCommand
     qreal mNewProbability;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/changewangsetdata.cpp b/src/tiled/changewangsetdata.cpp
index f004195d3d..22bf6e673c 100644
--- a/src/tiled/changewangsetdata.cpp
+++ b/src/tiled/changewangsetdata.cpp
@@ -30,7 +30,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Internal;
 
 ChangeWangSetEdgeCount::ChangeWangSetEdgeCount(TilesetDocument *tilesetDocument,
                                                WangSet *wangSet,
diff --git a/src/tiled/changewangsetdata.h b/src/tiled/changewangsetdata.h
index 59457a2d94..7ec7153a84 100644
--- a/src/tiled/changewangsetdata.h
+++ b/src/tiled/changewangsetdata.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class Tileset;
 class Tile;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class ChangeWangSetEdgeCount : public QUndoCommand
@@ -119,5 +117,4 @@ class SetWangSetImage : public QUndoCommand
     int mNewImageTileId;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/clickablelabel.cpp b/src/tiled/clickablelabel.cpp
index a66a7990d5..96d2427b5a 100644
--- a/src/tiled/clickablelabel.cpp
+++ b/src/tiled/clickablelabel.cpp
@@ -21,7 +21,6 @@
 #include "clickablelabel.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ClickableLabel::ClickableLabel(QWidget *parent) :
     QLabel(parent)
diff --git a/src/tiled/clickablelabel.h b/src/tiled/clickablelabel.h
index 74e8077b1e..c21de35b6c 100644
--- a/src/tiled/clickablelabel.h
+++ b/src/tiled/clickablelabel.h
@@ -23,7 +23,6 @@
 #include <QLabel>
 
 namespace Tiled {
-namespace Internal {
 
 class ClickableLabel : public QLabel
 {
@@ -44,4 +43,3 @@ class ClickableLabel : public QLabel
 };
 
 } // namespace Tiled
-} // namespace Internal
diff --git a/src/tiled/clipboardmanager.cpp b/src/tiled/clipboardmanager.cpp
index f4f6772c31..4b84842778 100644
--- a/src/tiled/clipboardmanager.cpp
+++ b/src/tiled/clipboardmanager.cpp
@@ -44,7 +44,6 @@
 static const char * const TMX_MIMETYPE = "text/tmx";
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ClipboardManager *ClipboardManager::mInstance;
 
diff --git a/src/tiled/clipboardmanager.h b/src/tiled/clipboardmanager.h
index ef73e02f51..3dcf6d5605 100644
--- a/src/tiled/clipboardmanager.h
+++ b/src/tiled/clipboardmanager.h
@@ -31,8 +31,6 @@ namespace Tiled {
 class ObjectGroup;
 class Map;
 
-namespace Internal {
-
 class MapDocument;
 class MapView;
 
@@ -107,5 +105,4 @@ inline bool ClipboardManager::hasProperties() const
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(ClipboardManager::PasteFlags)
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/colorbutton.cpp b/src/tiled/colorbutton.cpp
index 8f36566ddb..791ed547cf 100644
--- a/src/tiled/colorbutton.cpp
+++ b/src/tiled/colorbutton.cpp
@@ -26,7 +26,6 @@
 #include <QStyle>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ColorButton::ColorButton(QWidget *parent)
     : QToolButton(parent)
diff --git a/src/tiled/colorbutton.h b/src/tiled/colorbutton.h
index 82d3e8f6e4..bb55fc109b 100644
--- a/src/tiled/colorbutton.h
+++ b/src/tiled/colorbutton.h
@@ -24,7 +24,6 @@
 #include <QToolButton>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A tool button for letting the user pick a color. When clicked it shows a
@@ -53,5 +52,4 @@ class ColorButton : public QToolButton
     QColor mColor;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/command.cpp b/src/tiled/command.cpp
index d36109b0ca..f08aa72a4f 100644
--- a/src/tiled/command.cpp
+++ b/src/tiled/command.cpp
@@ -31,7 +31,6 @@
 #include <QStandardPaths>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 QString Command::finalWorkingDirectory() const
 {
diff --git a/src/tiled/command.h b/src/tiled/command.h
index a023c93cb5..5c40fc23f3 100644
--- a/src/tiled/command.h
+++ b/src/tiled/command.h
@@ -30,7 +30,6 @@
 #endif
 
 namespace Tiled {
-namespace Internal {
 
 struct Command
 {
@@ -110,5 +109,4 @@ private slots:
 #endif
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/commandbutton.cpp b/src/tiled/commandbutton.cpp
index 30e188e677..eff4fddcfe 100644
--- a/src/tiled/commandbutton.cpp
+++ b/src/tiled/commandbutton.cpp
@@ -30,7 +30,6 @@
 
 using namespace Tiled;
 using namespace Tiled::Utils;
-using namespace Tiled::Internal;
 
 CommandButton::CommandButton(QWidget *parent)
     : QToolButton(parent)
diff --git a/src/tiled/commandbutton.h b/src/tiled/commandbutton.h
index 0605ddf0ea..9115ba8511 100644
--- a/src/tiled/commandbutton.h
+++ b/src/tiled/commandbutton.h
@@ -25,7 +25,6 @@
 class QMenu;
 
 namespace Tiled {
-namespace Internal {
 
 class MainWindow;
 class DocumentManager;
@@ -50,5 +49,4 @@ private slots:
     QMenu *mMenu;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/commanddatamodel.cpp b/src/tiled/commanddatamodel.cpp
index a7742b3bfc..d7f5d51b42 100644
--- a/src/tiled/commanddatamodel.cpp
+++ b/src/tiled/commanddatamodel.cpp
@@ -27,7 +27,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 static const char *commandMimeType = "application/x-tiled-commandptr";
 
diff --git a/src/tiled/commanddatamodel.h b/src/tiled/commanddatamodel.h
index 2b3d470ad6..5fa5dbce51 100644
--- a/src/tiled/commanddatamodel.h
+++ b/src/tiled/commanddatamodel.h
@@ -28,7 +28,6 @@
 class QMenu;
 
 namespace Tiled {
-namespace Internal {
 
 class CommandDataModel : public QAbstractTableModel
 {
@@ -175,5 +174,4 @@ public slots:
     QList<Command> mCommands;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/commanddialog.cpp b/src/tiled/commanddialog.cpp
index b22360b1cc..d49666c9fa 100644
--- a/src/tiled/commanddialog.cpp
+++ b/src/tiled/commanddialog.cpp
@@ -33,7 +33,6 @@
 #include <QStandardPaths>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CommandDialog::CommandDialog(QWidget *parent)
     : QDialog(parent)
diff --git a/src/tiled/commanddialog.h b/src/tiled/commanddialog.h
index a7bc6f2be8..86ab42b78e 100644
--- a/src/tiled/commanddialog.h
+++ b/src/tiled/commanddialog.h
@@ -28,7 +28,6 @@ class CommandDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 class CommandDataModel;
 
@@ -101,5 +100,4 @@ private slots:
     CommandDataModel *mModel;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/commanddialog.ui b/src/tiled/commanddialog.ui
index dcb0b1051e..215047f7ab 100644
--- a/src/tiled/commanddialog.ui
+++ b/src/tiled/commanddialog.ui
@@ -24,7 +24,7 @@
   </property>
   <layout class="QGridLayout" name="gridLayout_2">
    <item row="0" column="0">
-    <widget class="Tiled::Internal::CommandTreeView" name="treeView">
+    <widget class="Tiled::CommandTreeView" name="treeView">
      <property name="sizePolicy">
       <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
        <horstretch>0</horstretch>
@@ -197,7 +197,7 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>Tiled::Internal::CommandTreeView</class>
+   <class>Tiled::CommandTreeView</class>
    <extends>QTreeView</extends>
    <header>commanddialog.h</header>
   </customwidget>
diff --git a/src/tiled/commandlineparser.cpp b/src/tiled/commandlineparser.cpp
index e43fb7850b..880f509f92 100644
--- a/src/tiled/commandlineparser.cpp
+++ b/src/tiled/commandlineparser.cpp
@@ -27,7 +27,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CommandLineParser::CommandLineParser()
     : mLongestArgument(0)
diff --git a/src/tiled/commandlineparser.h b/src/tiled/commandlineparser.h
index e32319f483..fa7bb89fa1 100644
--- a/src/tiled/commandlineparser.h
+++ b/src/tiled/commandlineparser.h
@@ -26,7 +26,6 @@
 #include <QVector>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * C-style callback function taking an arbitrary data pointer.
@@ -145,5 +144,4 @@ class CommandLineParser
     bool mShowHelp;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/commandmanager.cpp b/src/tiled/commandmanager.cpp
index 442d990c8e..6bb5cc1d37 100644
--- a/src/tiled/commandmanager.cpp
+++ b/src/tiled/commandmanager.cpp
@@ -32,7 +32,6 @@
 #include <QMenu>
 
 namespace Tiled {
-namespace Internal {
 
 CommandManager *CommandManager::mInstance;
 
@@ -135,5 +134,4 @@ void CommandManager::retranslateUi()
     mEditCommands->setText(tr("Edit Commands..."));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/commandmanager.h b/src/tiled/commandmanager.h
index 87d63311da..b1b3d939ad 100644
--- a/src/tiled/commandmanager.h
+++ b/src/tiled/commandmanager.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class LoggingInterface;
 
-namespace Internal {
-
 class CommandDataModel;
 
 class CommandManager : public QObject
@@ -86,5 +84,4 @@ public slots:
     LoggingInterface *mLogger;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/consoledock.cpp b/src/tiled/consoledock.cpp
index f3bf90cffb..a9f64c904b 100644
--- a/src/tiled/consoledock.cpp
+++ b/src/tiled/consoledock.cpp
@@ -30,7 +30,6 @@
 #include <QVBoxLayout>
 
 namespace Tiled {
-namespace Internal {
 
 ConsoleDock::ConsoleDock(QWidget *parent)
     : QDockWidget(parent)
@@ -167,5 +166,4 @@ void ConsoleDock::registerOutput(LoggingInterface *output)
     connect(output, &LoggingInterface::error, this, &ConsoleDock::appendError);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/consoledock.h b/src/tiled/consoledock.h
index 703ddddd37..c0fa4a08f5 100644
--- a/src/tiled/consoledock.h
+++ b/src/tiled/consoledock.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class LoggingInterface;
 
-namespace Internal {
-
 class ConsoleDock : public QDockWidget
 {
     Q_OBJECT
@@ -58,5 +56,4 @@ private slots:
     int mHistoryPosition = 0;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createellipseobjecttool.cpp b/src/tiled/createellipseobjecttool.cpp
index 17b1cecf27..158aadea8c 100644
--- a/src/tiled/createellipseobjecttool.cpp
+++ b/src/tiled/createellipseobjecttool.cpp
@@ -24,7 +24,6 @@
 #include "utils.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreateEllipseObjectTool::CreateEllipseObjectTool(QObject *parent)
     : CreateScalableObjectTool(parent)
diff --git a/src/tiled/createellipseobjecttool.h b/src/tiled/createellipseobjecttool.h
index 7378ffeb7a..3d48861a8f 100644
--- a/src/tiled/createellipseobjecttool.h
+++ b/src/tiled/createellipseobjecttool.h
@@ -23,7 +23,6 @@
 #include "createscalableobjecttool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class CreateEllipseObjectTool : public CreateScalableObjectTool
 {
@@ -41,5 +40,4 @@ class CreateEllipseObjectTool : public CreateScalableObjectTool
     void languageChangedImpl();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createobjecttool.cpp b/src/tiled/createobjecttool.cpp
index ad6b0bf654..43e0edab84 100644
--- a/src/tiled/createobjecttool.cpp
+++ b/src/tiled/createobjecttool.cpp
@@ -41,7 +41,6 @@
 #include <QPalette>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreateObjectTool::CreateObjectTool(QObject *parent)
     : AbstractObjectTool(QString(),
diff --git a/src/tiled/createobjecttool.h b/src/tiled/createobjecttool.h
index 804c060d27..ac7a52007e 100644
--- a/src/tiled/createobjecttool.h
+++ b/src/tiled/createobjecttool.h
@@ -28,8 +28,6 @@ namespace Tiled {
 
 class Tile;
 
-namespace Internal {
-
 class MapObjectItem;
 class ObjectGroupItem;
 
@@ -95,5 +93,4 @@ class CreateObjectTool : public AbstractObjectTool
     std::unique_ptr<ObjectGroupItem> mObjectGroupItem;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createpointobjecttool.cpp b/src/tiled/createpointobjecttool.cpp
index 50b87f69c9..bea8311c25 100644
--- a/src/tiled/createpointobjecttool.cpp
+++ b/src/tiled/createpointobjecttool.cpp
@@ -28,7 +28,6 @@
 #include "utils.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreatePointObjectTool::CreatePointObjectTool(QObject *parent)
     : CreateObjectTool(parent)
diff --git a/src/tiled/createpointobjecttool.h b/src/tiled/createpointobjecttool.h
index 128cb0bcb7..6ff691fa98 100644
--- a/src/tiled/createpointobjecttool.h
+++ b/src/tiled/createpointobjecttool.h
@@ -23,7 +23,6 @@
 #include "createobjecttool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class CreatePointObjectTool : public CreateObjectTool
 {
@@ -41,5 +40,4 @@ class CreatePointObjectTool : public CreateObjectTool
     void languageChangedImpl();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createpolygonobjecttool.cpp b/src/tiled/createpolygonobjecttool.cpp
index 0b9ccecd74..b14f0597b1 100644
--- a/src/tiled/createpolygonobjecttool.cpp
+++ b/src/tiled/createpolygonobjecttool.cpp
@@ -46,7 +46,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreatePolygonObjectTool::CreatePolygonObjectTool(QObject *parent)
     : CreateObjectTool(parent)
diff --git a/src/tiled/createpolygonobjecttool.h b/src/tiled/createpolygonobjecttool.h
index 2f4a671f4c..ac3c9a1b86 100644
--- a/src/tiled/createpolygonobjecttool.h
+++ b/src/tiled/createpolygonobjecttool.h
@@ -25,7 +25,6 @@
 
 namespace Tiled {
 
-namespace Internal {
 
 class PointHandle;
 
@@ -101,5 +100,4 @@ private slots:
     PointHandle *mClickedHandle;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createrectangleobjecttool.cpp b/src/tiled/createrectangleobjecttool.cpp
index e70ab74e24..989b4af40f 100644
--- a/src/tiled/createrectangleobjecttool.cpp
+++ b/src/tiled/createrectangleobjecttool.cpp
@@ -24,7 +24,6 @@
 #include "utils.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreateRectangleObjectTool::CreateRectangleObjectTool(QObject *parent)
     : CreateScalableObjectTool(parent)
diff --git a/src/tiled/createrectangleobjecttool.h b/src/tiled/createrectangleobjecttool.h
index d68febdaeb..30bc32356e 100644
--- a/src/tiled/createrectangleobjecttool.h
+++ b/src/tiled/createrectangleobjecttool.h
@@ -23,7 +23,6 @@
 #include "createscalableobjecttool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class CreateRectangleObjectTool : public CreateScalableObjectTool
 {
@@ -41,5 +40,4 @@ class CreateRectangleObjectTool : public CreateScalableObjectTool
     void languageChangedImpl();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createscalableobjecttool.cpp b/src/tiled/createscalableobjecttool.cpp
index 66c9063f3c..6967c3e133 100644
--- a/src/tiled/createscalableobjecttool.cpp
+++ b/src/tiled/createscalableobjecttool.cpp
@@ -28,7 +28,6 @@
 #include "utils.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreateScalableObjectTool::CreateScalableObjectTool(QObject *parent)
     : CreateObjectTool(parent)
diff --git a/src/tiled/createscalableobjecttool.h b/src/tiled/createscalableobjecttool.h
index 5ca72def99..89554c839b 100644
--- a/src/tiled/createscalableobjecttool.h
+++ b/src/tiled/createscalableobjecttool.h
@@ -23,7 +23,6 @@
 #include "createobjecttool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class CreateScalableObjectTool : public CreateObjectTool
 {
@@ -42,5 +41,4 @@ class CreateScalableObjectTool : public CreateObjectTool
     QPointF mStartPos;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createtemplatetool.cpp b/src/tiled/createtemplatetool.cpp
index 5cfdde58a7..b144b1723e 100644
--- a/src/tiled/createtemplatetool.cpp
+++ b/src/tiled/createtemplatetool.cpp
@@ -30,7 +30,6 @@
 #include "utils.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreateTemplateTool::CreateTemplateTool(QObject *parent)
     : CreateObjectTool(parent)
diff --git a/src/tiled/createtemplatetool.h b/src/tiled/createtemplatetool.h
index 8a8b86f3e1..4928f33ab8 100644
--- a/src/tiled/createtemplatetool.h
+++ b/src/tiled/createtemplatetool.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class ObjectTemplate;
 
-namespace Internal {
-
 class CreateTemplateTool : public CreateObjectTool
 {
     Q_OBJECT
@@ -45,5 +43,4 @@ class CreateTemplateTool : public CreateObjectTool
     void languageChangedImpl();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createtextobjecttool.cpp b/src/tiled/createtextobjecttool.cpp
index b5313cc154..61407ef80c 100644
--- a/src/tiled/createtextobjecttool.cpp
+++ b/src/tiled/createtextobjecttool.cpp
@@ -28,7 +28,6 @@
 #include "utils.h"
 
 namespace Tiled {
-namespace Internal {
 
 CreateTextObjectTool::CreateTextObjectTool(QObject *parent)
     : CreateObjectTool(parent)
@@ -78,5 +77,4 @@ MapObject *CreateTextObjectTool::createNewMapObject()
     return newMapObject;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createtextobjecttool.h b/src/tiled/createtextobjecttool.h
index b511a88c36..bfab5d5ca1 100644
--- a/src/tiled/createtextobjecttool.h
+++ b/src/tiled/createtextobjecttool.h
@@ -23,7 +23,6 @@
 #include "createobjecttool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class CreateTextObjectTool : public CreateObjectTool
 {
@@ -44,5 +43,4 @@ class CreateTextObjectTool : public CreateObjectTool
     void languageChangedImpl();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/createtileobjecttool.cpp b/src/tiled/createtileobjecttool.cpp
index 76e02ad168..641ff01624 100644
--- a/src/tiled/createtileobjecttool.cpp
+++ b/src/tiled/createtileobjecttool.cpp
@@ -29,7 +29,6 @@
 #include "utils.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 CreateTileObjectTool::CreateTileObjectTool(QObject *parent)
     : CreateObjectTool(parent)
diff --git a/src/tiled/createtileobjecttool.h b/src/tiled/createtileobjecttool.h
index db477c0d10..610aac82d2 100644
--- a/src/tiled/createtileobjecttool.h
+++ b/src/tiled/createtileobjecttool.h
@@ -24,7 +24,6 @@
 
 namespace Tiled {
 
-namespace Internal {
 
 class CreateTileObjectTool : public CreateObjectTool
 {
@@ -45,5 +44,4 @@ class CreateTileObjectTool : public CreateObjectTool
     void languageChangedImpl();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/document.cpp b/src/tiled/document.cpp
index 5af73813ef..fc1ce5ba7c 100644
--- a/src/tiled/document.cpp
+++ b/src/tiled/document.cpp
@@ -28,7 +28,6 @@
 #include <QUndoStack>
 
 namespace Tiled {
-namespace Internal {
 
 QList<Document*> Document::sDocumentInstances;
 
@@ -133,5 +132,4 @@ void Document::setChangedOnDisk(bool changedOnDisk)
     mChangedOnDisk = changedOnDisk;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/document.h b/src/tiled/document.h
index ef5ec969cc..840e05c9f5 100644
--- a/src/tiled/document.h
+++ b/src/tiled/document.h
@@ -37,8 +37,6 @@ class FileFormat;
 class Object;
 class Tile;
 
-namespace Internal {
-
 class EditableAsset;
 
 /**
@@ -92,7 +90,7 @@ class Document : public QObject,
     QUndoStack *undoStack();
     bool isModified() const;
 
-    Q_INVOKABLE virtual Tiled::Internal::EditableAsset *editable() = 0;
+    Q_INVOKABLE virtual Tiled::EditableAsset *editable() = 0;
 
     Object *currentObject() const { return mCurrentObject; }
     void setCurrentObject(Object *object);
@@ -188,5 +186,4 @@ inline const QList<Document *> &Document::documentInstances()
 
 using DocumentPtr = QSharedPointer<Document>;
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/documentmanager.cpp b/src/tiled/documentmanager.cpp
index 2bb34e5d9a..d2054c9606 100644
--- a/src/tiled/documentmanager.cpp
+++ b/src/tiled/documentmanager.cpp
@@ -63,7 +63,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 
 DocumentManager *DocumentManager::mInstance;
@@ -497,7 +496,7 @@ bool DocumentManager::saveDocument(Document *document, const QString &fileName)
 
     QString error;
     if (!document->save(fileName, &error)) {
-        QMessageBox::critical(mWidget->window(), QCoreApplication::translate("Tiled::Internal::MainWindow", "Error Saving File"), error);
+        QMessageBox::critical(mWidget->window(), QCoreApplication::translate("Tiled::MainWindow", "Error Saving File"), error);
         return false;
     }
 
@@ -540,12 +539,12 @@ bool DocumentManager::saveDocumentAs(Document *document)
                 !Utils::fileNameMatchesNameFilter(QFileInfo(fileName).fileName(), selectedFilter))
             {
                 QMessageBox messageBox(QMessageBox::Warning,
-                                       QCoreApplication::translate("Tiled::Internal::MainWindow", "Extension Mismatch"),
-                                       QCoreApplication::translate("Tiled::Internal::MainWindow", "The file extension does not match the chosen file type."),
+                                       QCoreApplication::translate("Tiled::MainWindow", "Extension Mismatch"),
+                                       QCoreApplication::translate("Tiled::MainWindow", "The file extension does not match the chosen file type."),
                                        QMessageBox::Yes | QMessageBox::No,
                                        mWidget->window());
 
-                messageBox.setInformativeText(QCoreApplication::translate("Tiled::Internal::MainWindow",
+                messageBox.setInformativeText(QCoreApplication::translate("Tiled::MainWindow",
                                                                           "Tiled may not automatically recognize your file when loading. "
                                                                           "Are you sure you want to save with this extension?"));
 
@@ -564,7 +563,7 @@ bool DocumentManager::saveDocumentAs(Document *document)
         FormatHelper<MapFormat> helper(FileFormat::ReadWrite);
         filter = helper.filter();
 
-        auto suggestedFileName = QCoreApplication::translate("Tiled::Internal::MainWindow", "untitled");
+        auto suggestedFileName = QCoreApplication::translate("Tiled::MainWindow", "untitled");
         suggestedFileName.append(QLatin1String(".tmx"));
 
         fileName = getSaveFileName(suggestedFileName);
@@ -584,7 +583,7 @@ bool DocumentManager::saveDocumentAs(Document *document)
 
         auto suggestedFileName = tilesetDocument->tileset()->name().trimmed();
         if (suggestedFileName.isEmpty())
-            suggestedFileName = QCoreApplication::translate("Tiled::Internal::MainWindow", "untitled");
+            suggestedFileName = QCoreApplication::translate("Tiled::MainWindow", "untitled");
         suggestedFileName.append(QLatin1String(".tsx"));
 
         fileName = getSaveFileName(suggestedFileName);
diff --git a/src/tiled/documentmanager.h b/src/tiled/documentmanager.h
index 31549eea4d..cc8a6e456e 100644
--- a/src/tiled/documentmanager.h
+++ b/src/tiled/documentmanager.h
@@ -40,8 +40,6 @@ namespace Tiled {
 class FileSystemWatcher;
 class ObjectTemplate;
 
-namespace Internal {
-
 class AbstractTool;
 class BrokenLinksModel;
 class BrokenLinksWidget;
@@ -254,5 +252,4 @@ inline TilesetDocumentsModel *DocumentManager::tilesetDocumentsModel() const
     return mTilesetDocumentsModel;
 }
 
-} // namespace Tiled::Internal
 } // namespace Tiled
diff --git a/src/tiled/editableasset.cpp b/src/tiled/editableasset.cpp
index 61967305d8..3871fd891c 100644
--- a/src/tiled/editableasset.cpp
+++ b/src/tiled/editableasset.cpp
@@ -23,7 +23,6 @@
 #include <QUndoStack>
 
 namespace Tiled {
-namespace Internal {
 
 EditableAsset::EditableAsset(QObject *parent)
     : QObject(parent)
@@ -55,5 +54,4 @@ void EditableAsset::redo()
     undoStack()->redo();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editableasset.h b/src/tiled/editableasset.h
index b60c08d0a8..3e995e9438 100644
--- a/src/tiled/editableasset.h
+++ b/src/tiled/editableasset.h
@@ -26,7 +26,6 @@ class QUndoCommand;
 class QUndoStack;
 
 namespace Tiled {
-namespace Internal {
 
 class EditableAsset : public QObject
 {
@@ -62,7 +61,6 @@ inline QUndoStack *EditableAsset::undoStack() const
     return mUndoStack;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::EditableAsset*)
+Q_DECLARE_METATYPE(Tiled::EditableAsset*)
diff --git a/src/tiled/editablelayer.cpp b/src/tiled/editablelayer.cpp
index f358e001ed..4338e642e5 100644
--- a/src/tiled/editablelayer.cpp
+++ b/src/tiled/editablelayer.cpp
@@ -26,7 +26,6 @@
 #include "scriptmanager.h"
 
 namespace Tiled {
-namespace Internal {
 
 EditableLayer::EditableLayer(EditableMap *map, Layer *layer, QObject *parent)
     : QObject(parent)
@@ -98,5 +97,4 @@ void EditableLayer::setOffset(QPointF offset)
         mLayer->setOffset(offset);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editablelayer.h b/src/tiled/editablelayer.h
index 2d8e80327d..8922fd5a05 100644
--- a/src/tiled/editablelayer.h
+++ b/src/tiled/editablelayer.h
@@ -27,7 +27,6 @@
 #include <memory>
 
 namespace Tiled {
-namespace Internal {
 
 class EditableMap;
 
@@ -40,7 +39,7 @@ class EditableLayer : public QObject
     Q_PROPERTY(bool visible READ isVisible WRITE setVisible)
     Q_PROPERTY(bool locked READ isLocked WRITE setLocked)
     Q_PROPERTY(QPointF offset READ offset WRITE setOffset)
-    Q_PROPERTY(Tiled::Internal::EditableMap *map READ map)
+    Q_PROPERTY(Tiled::EditableMap *map READ map)
 
 public:
     explicit EditableLayer(EditableMap *map,
@@ -109,7 +108,6 @@ inline Layer *EditableLayer::layer() const
     return mLayer;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::EditableLayer*)
+Q_DECLARE_METATYPE(Tiled::EditableLayer*)
diff --git a/src/tiled/editablemap.cpp b/src/tiled/editablemap.cpp
index ac278f371e..6e4b105230 100644
--- a/src/tiled/editablemap.cpp
+++ b/src/tiled/editablemap.cpp
@@ -44,7 +44,6 @@
 #include "qtcompat_p.h"
 
 namespace Tiled {
-namespace Internal {
 
 EditableMap::EditableMap(MapDocument *mapDocument, QObject *parent)
     : EditableAsset(parent)
@@ -293,5 +292,4 @@ void EditableMap::editableLayerDeleted(EditableLayer *editableLayer)
     mEditableLayers.remove(editableLayer->layer());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editablemap.h b/src/tiled/editablemap.h
index b49208714f..b17c7133bc 100644
--- a/src/tiled/editablemap.h
+++ b/src/tiled/editablemap.h
@@ -25,7 +25,6 @@
 #include "mapdocument.h"
 
 namespace Tiled {
-namespace Internal {
 
 class EditableLayer;
 
@@ -46,7 +45,7 @@ class EditableMap : public EditableAsset
     Q_PROPERTY(Tiled::Map::RenderOrder renderOrder READ renderOrder WRITE setRenderOrder)
     Q_PROPERTY(QColor backgroundColor READ backgroundColor WRITE setBackgroundColor)
     Q_PROPERTY(Tiled::Map::LayerDataFormat layerDataFormat READ layerDataFormat WRITE setLayerDataFormat)
-    Q_PROPERTY(Tiled::Internal::EditableSelectedArea *selectedArea READ selectedArea CONSTANT)
+    Q_PROPERTY(Tiled::EditableSelectedArea *selectedArea READ selectedArea CONSTANT)
     Q_PROPERTY(int layerCount READ layerCount)
 
 public:
@@ -70,9 +69,9 @@ class EditableMap : public EditableAsset
     QColor backgroundColor() const;
     Map::LayerDataFormat layerDataFormat() const;
     int layerCount() const;
-    Q_INVOKABLE Tiled::Internal::EditableLayer *layerAt(int index);
+    Q_INVOKABLE Tiled::EditableLayer *layerAt(int index);
     Q_INVOKABLE void removeLayerAt(int index);
-    Q_INVOKABLE void insertLayerAt(int index, Tiled::Internal::EditableLayer *layer);
+    Q_INVOKABLE void insertLayerAt(int index, Tiled::EditableLayer *layer);
 
     void setTileWidth(int value);
     void setTileHeight(int value);
@@ -206,7 +205,6 @@ inline EditableSelectedArea *EditableMap::selectedArea()
     return &mSelectedArea;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::EditableMap*)
+Q_DECLARE_METATYPE(Tiled::EditableMap*)
diff --git a/src/tiled/editableselectedarea.cpp b/src/tiled/editableselectedarea.cpp
index 251d4a3927..a22e5580a2 100644
--- a/src/tiled/editableselectedarea.cpp
+++ b/src/tiled/editableselectedarea.cpp
@@ -26,7 +26,6 @@
 #include <QUndoStack>
 
 namespace Tiled {
-namespace Internal {
 
 EditableSelectedArea::EditableSelectedArea(MapDocument *mapDocument, QObject *parent)
     : QObject(parent)
@@ -82,5 +81,4 @@ void EditableSelectedArea::set(const QRegion &region)
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editableselectedarea.h b/src/tiled/editableselectedarea.h
index 493662e0da..bc0f331205 100644
--- a/src/tiled/editableselectedarea.h
+++ b/src/tiled/editableselectedarea.h
@@ -28,7 +28,6 @@
 class QUndoCommand;
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -43,16 +42,16 @@ class EditableSelectedArea : public QObject
 public slots:
     void set(const QRect &rect);
     void set(const QRectF &rect);
-    void set(const Tiled::Internal::RegionValueType &region);
+    void set(const Tiled::RegionValueType &region);
     void add(const QRect &rect);
     void add(const QRectF &rect);
-    void add(const Tiled::Internal::RegionValueType &region);
+    void add(const Tiled::RegionValueType &region);
     void subtract(const QRect &rect);
     void subtract(const QRectF &rect);
-    void subtract(const Tiled::Internal::RegionValueType &region);
+    void subtract(const Tiled::RegionValueType &region);
     void intersect(const QRect &rect);
     void intersect(const QRectF &rect);
-    void intersect(const Tiled::Internal::RegionValueType &region);
+    void intersect(const Tiled::RegionValueType &region);
 
 private:
     void set(const QRegion &region);
@@ -81,5 +80,4 @@ inline void EditableSelectedArea::intersect(const QRectF &rect)
     intersect(rect.toRect());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editabletilelayer.cpp b/src/tiled/editabletilelayer.cpp
index ce39fb67a3..12b1fb4835 100644
--- a/src/tiled/editabletilelayer.cpp
+++ b/src/tiled/editabletilelayer.cpp
@@ -21,7 +21,6 @@
 #include "editabletilelayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 EditableTileLayer::EditableTileLayer(EditableMap *map,
                                      TileLayer *layer,
@@ -40,5 +39,4 @@ Cell EditableTileLayer::cellAt(int x, int y) const
     return tileLayer()->cellAt(x, y);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editabletilelayer.h b/src/tiled/editabletilelayer.h
index 919005ccdc..d581faf08b 100644
--- a/src/tiled/editabletilelayer.h
+++ b/src/tiled/editabletilelayer.h
@@ -25,7 +25,6 @@
 #include "tilelayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class EditableTileLayer : public EditableLayer
 {
@@ -45,7 +44,7 @@ class EditableTileLayer : public EditableLayer
     int height() const;
     QSize size() const;
 
-    Q_INVOKABLE Tiled::Internal::RegionValueType region() const;
+    Q_INVOKABLE Tiled::RegionValueType region() const;
 
     Tiled::Cell cell() const { return Tiled::Cell(); }
     Q_INVOKABLE Tiled::Cell cellAt(int x, int y) const;
@@ -79,7 +78,6 @@ inline TileLayer *EditableTileLayer::tileLayer() const
     return static_cast<TileLayer*>(layer());
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::EditableTileLayer*)
+Q_DECLARE_METATYPE(Tiled::EditableTileLayer*)
diff --git a/src/tiled/editabletileset.cpp b/src/tiled/editabletileset.cpp
index 399ddc7dd6..6c767370fe 100644
--- a/src/tiled/editabletileset.cpp
+++ b/src/tiled/editabletileset.cpp
@@ -24,7 +24,6 @@
 #include "tilesetdocument.h"
 
 namespace Tiled {
-namespace Internal {
 
 EditableTileset::EditableTileset(TilesetDocument *tilesetDocument,
                                  QObject *parent)
@@ -59,5 +58,4 @@ Tileset *EditableTileset::tileset() const
     return mTilesetDocument->tileset().data();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editabletileset.h b/src/tiled/editabletileset.h
index dbfe301d4a..51badd6b60 100644
--- a/src/tiled/editabletileset.h
+++ b/src/tiled/editabletileset.h
@@ -24,7 +24,6 @@
 #include "tileset.h"
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetDocument;
 
@@ -108,7 +107,6 @@ inline QColor EditableTileset::backgroundColor() const
     return tileset()->backgroundColor();
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::EditableTileset*)
+Q_DECLARE_METATYPE(Tiled::EditableTileset*)
diff --git a/src/tiled/editor.cpp b/src/tiled/editor.cpp
index 8deb724878..de5109d7b1 100644
--- a/src/tiled/editor.cpp
+++ b/src/tiled/editor.cpp
@@ -21,12 +21,10 @@
 #include "editor.h"
 
 namespace Tiled {
-namespace Internal {
 
 Editor::Editor(QObject *parent)
     : QObject(parent)
 {
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editor.h b/src/tiled/editor.h
index 2822426c9b..79c760e05d 100644
--- a/src/tiled/editor.h
+++ b/src/tiled/editor.h
@@ -26,7 +26,6 @@ class QToolBar;
 class QDockWidget;
 
 namespace Tiled {
-namespace Internal {
 
 class Document;
 class Zoomable;
@@ -74,5 +73,4 @@ class Editor : public QObject
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(Editor::StandardActions)
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/editpolygontool.cpp b/src/tiled/editpolygontool.cpp
index 71d3dd476b..ad8032429b 100644
--- a/src/tiled/editpolygontool.cpp
+++ b/src/tiled/editpolygontool.cpp
@@ -52,7 +52,6 @@
 #include <cstdlib>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 EditPolygonTool::EditPolygonTool(QObject *parent)
     : AbstractObjectTool(tr("Edit Polygons"),
diff --git a/src/tiled/editpolygontool.h b/src/tiled/editpolygontool.h
index dec4865591..1dbe5357b4 100644
--- a/src/tiled/editpolygontool.h
+++ b/src/tiled/editpolygontool.h
@@ -30,7 +30,6 @@
 class QGraphicsItem;
 
 namespace Tiled {
-namespace Internal {
 
 class PointHandle;
 class SelectionRectangle;
@@ -136,5 +135,4 @@ private slots:
     QSet<PointHandle*> mHighlightedHandles;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/eraser.cpp b/src/tiled/eraser.cpp
index 71497c85ce..ba64d9eb60 100644
--- a/src/tiled/eraser.cpp
+++ b/src/tiled/eraser.cpp
@@ -29,7 +29,6 @@
 #include "tilelayer.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 Eraser::Eraser(QObject *parent)
     : AbstractTileTool(tr("Eraser"),
diff --git a/src/tiled/eraser.h b/src/tiled/eraser.h
index 0ab8a1b18c..6a86febffe 100644
--- a/src/tiled/eraser.h
+++ b/src/tiled/eraser.h
@@ -23,7 +23,6 @@
 #include "abstracttiletool.h"
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Implements a simple eraser tool.
@@ -58,5 +57,4 @@ class Eraser : public AbstractTileTool
     QPoint mStart;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/erasetiles.cpp b/src/tiled/erasetiles.cpp
index a29c7e543b..a4258b4e97 100644
--- a/src/tiled/erasetiles.cpp
+++ b/src/tiled/erasetiles.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 EraseTiles::EraseTiles(MapDocument *mapDocument,
                        TileLayer *tileLayer,
diff --git a/src/tiled/erasetiles.h b/src/tiled/erasetiles.h
index d8d50049c3..4643fc19c3 100644
--- a/src/tiled/erasetiles.h
+++ b/src/tiled/erasetiles.h
@@ -31,8 +31,6 @@ namespace Tiled {
 class Tile;
 class TileLayer;
 
-namespace Internal {
-
 class MapDocument;
 
 class EraseTiles : public QUndoCommand
@@ -69,5 +67,4 @@ class EraseTiles : public QUndoCommand
     bool mMergeable;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/exportasimagedialog.cpp b/src/tiled/exportasimagedialog.cpp
index 792757c762..419254d73e 100644
--- a/src/tiled/exportasimagedialog.cpp
+++ b/src/tiled/exportasimagedialog.cpp
@@ -44,7 +44,6 @@ static const char * const DRAW_GRID_KEY = "SaveAsImage/DrawGrid";
 static const char * const INCLUDE_BACKGROUND_COLOR = "SaveAsImage/IncludeBackgroundColor";
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 QString ExportAsImageDialog::mPath;
 
diff --git a/src/tiled/exportasimagedialog.h b/src/tiled/exportasimagedialog.h
index 4c599de0db..52a30597d1 100644
--- a/src/tiled/exportasimagedialog.h
+++ b/src/tiled/exportasimagedialog.h
@@ -27,7 +27,6 @@ class ExportAsImageDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -64,5 +63,4 @@ private slots:
     static QString mPath;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/exporthelper.cpp b/src/tiled/exporthelper.cpp
index 83b3a423a9..c85ce7f2d9 100644
--- a/src/tiled/exporthelper.cpp
+++ b/src/tiled/exporthelper.cpp
@@ -24,7 +24,6 @@
 #include "objectgroup.h"
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Prepares a tileset for export.
@@ -142,5 +141,4 @@ void ExportHelper::resolveTypeAndProperties(MapObject *object) const
     object->setProperties(properties);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/exporthelper.h b/src/tiled/exporthelper.h
index b08d0911a7..02a8f74764 100644
--- a/src/tiled/exporthelper.h
+++ b/src/tiled/exporthelper.h
@@ -26,7 +26,6 @@
 #include <memory>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Applies certain export options to a map and its tilesets, or to a specific
@@ -50,5 +49,4 @@ class ExportHelper
     const Preferences::ExportOptions mOptions;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/filechangedwarning.cpp b/src/tiled/filechangedwarning.cpp
index 6e6fbeb363..3f435c1fe0 100644
--- a/src/tiled/filechangedwarning.cpp
+++ b/src/tiled/filechangedwarning.cpp
@@ -27,7 +27,6 @@
 #include <QPushButton>
 
 namespace Tiled {
-namespace Internal {
 
 FileChangedWarning::FileChangedWarning(QWidget *parent)
     : QWidget(parent)
@@ -70,5 +69,4 @@ void FileChangedWarning::paintEvent(QPaintEvent *event)
 
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/filechangedwarning.h b/src/tiled/filechangedwarning.h
index a9018ba53a..d26b699464 100644
--- a/src/tiled/filechangedwarning.h
+++ b/src/tiled/filechangedwarning.h
@@ -26,7 +26,6 @@ class QLabel;
 class QDialogButtonBox;
 
 namespace Tiled {
-namespace Internal {
 
 class FileChangedWarning : public QWidget
 {
@@ -47,5 +46,4 @@ class FileChangedWarning : public QWidget
     QDialogButtonBox *mButtons;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/fileedit.cpp b/src/tiled/fileedit.cpp
index 780e4270d6..5496d4d61d 100644
--- a/src/tiled/fileedit.cpp
+++ b/src/tiled/fileedit.cpp
@@ -28,7 +28,6 @@
 #include <QToolButton>
 
 namespace Tiled {
-namespace Internal {
 
 FileEdit::FileEdit(QWidget *parent)
     : QWidget(parent)
@@ -133,5 +132,4 @@ void FileEdit::buttonClicked()
     emit fileUrlChanged(url);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/fileedit.h b/src/tiled/fileedit.h
index 0aa40b08ac..4277015c6f 100644
--- a/src/tiled/fileedit.h
+++ b/src/tiled/fileedit.h
@@ -27,7 +27,6 @@
 class QLineEdit;
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A widget that combines a line edit with a button to choose a file.
@@ -66,5 +65,4 @@ private slots:
     QColor mErrorTextColor;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/flexiblescrollbar.cpp b/src/tiled/flexiblescrollbar.cpp
index 5926edf99b..f08fbc2304 100644
--- a/src/tiled/flexiblescrollbar.cpp
+++ b/src/tiled/flexiblescrollbar.cpp
@@ -21,7 +21,6 @@
 #include "flexiblescrollbar.h"
 
 namespace Tiled {
-namespace Internal {
 
 FlexibleScrollBar::FlexibleScrollBar(Qt::Orientation orientation, QWidget *parent)
     : QScrollBar(orientation, parent)
@@ -97,5 +96,4 @@ void FlexibleScrollBar::setOverrideRange(int min, int max)
     mInternalRangeChange = false;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/flexiblescrollbar.h b/src/tiled/flexiblescrollbar.h
index 1df8780fed..4435f85386 100644
--- a/src/tiled/flexiblescrollbar.h
+++ b/src/tiled/flexiblescrollbar.h
@@ -23,7 +23,6 @@
 #include <QScrollBar>
 
 namespace Tiled {
-namespace Internal {
 
 class FlexibleScrollBar : public QScrollBar
 {
@@ -47,5 +46,4 @@ class FlexibleScrollBar : public QScrollBar
     bool mInternalRangeChange;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/flipmapobjects.cpp b/src/tiled/flipmapobjects.cpp
index 7d078ae40f..7d2c23c2e1 100644
--- a/src/tiled/flipmapobjects.cpp
+++ b/src/tiled/flipmapobjects.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 FlipMapObjects::FlipMapObjects(MapDocument *mapDocument,
                                const QList<MapObject *> &mapObjects,
diff --git a/src/tiled/flipmapobjects.h b/src/tiled/flipmapobjects.h
index 61e422588e..616bc7444d 100644
--- a/src/tiled/flipmapobjects.h
+++ b/src/tiled/flipmapobjects.h
@@ -26,7 +26,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -54,5 +53,4 @@ class FlipMapObjects : public QUndoCommand
     QVector<bool> mNewCellStates;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/grouplayeritem.cpp b/src/tiled/grouplayeritem.cpp
index fcd14c09b9..9b423c63ef 100644
--- a/src/tiled/grouplayeritem.cpp
+++ b/src/tiled/grouplayeritem.cpp
@@ -21,7 +21,6 @@
 #include "grouplayeritem.h"
 
 namespace Tiled {
-namespace Internal {
 
 GroupLayerItem::GroupLayerItem(GroupLayer *groupLayer, QGraphicsItem *parent)
     : LayerItem(groupLayer, parent)
@@ -41,5 +40,4 @@ void GroupLayerItem::paint(QPainter *,
 {
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/grouplayeritem.h b/src/tiled/grouplayeritem.h
index 93c957a5d0..dacefa752c 100644
--- a/src/tiled/grouplayeritem.h
+++ b/src/tiled/grouplayeritem.h
@@ -25,7 +25,6 @@
 #include "grouplayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class GroupLayerItem : public LayerItem
 {
@@ -46,5 +45,4 @@ inline GroupLayer *GroupLayerItem::groupLayer() const
     return static_cast<GroupLayer*>(layer());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/iconcheckdelegate.cpp b/src/tiled/iconcheckdelegate.cpp
index a180f20fc1..64ac120cca 100644
--- a/src/tiled/iconcheckdelegate.cpp
+++ b/src/tiled/iconcheckdelegate.cpp
@@ -27,7 +27,6 @@
 #include <QPainter>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 IconCheckDelegate::IconCheckDelegate(IconType icon,
                                      bool exclusive,
diff --git a/src/tiled/iconcheckdelegate.h b/src/tiled/iconcheckdelegate.h
index 27ba76894f..29f2e784ce 100644
--- a/src/tiled/iconcheckdelegate.h
+++ b/src/tiled/iconcheckdelegate.h
@@ -24,7 +24,6 @@
 #include <QIcon>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Delegate for drawing an icon in LayerView and ObjectsView for displaying
@@ -70,5 +69,4 @@ class IconCheckDelegate : public QItemDelegate
     bool mExclusive;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/id.cpp b/src/tiled/id.cpp
index dc4967109e..0547fe191f 100644
--- a/src/tiled/id.cpp
+++ b/src/tiled/id.cpp
@@ -27,7 +27,6 @@
 #include <QHash>
 
 namespace Tiled {
-namespace Internal {
 
 class StringHash
 {
@@ -85,5 +84,4 @@ QByteArray Id::name() const
     return stringFromId.value(mId).string;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/id.h b/src/tiled/id.h
index c80b313955..7d77e22a17 100644
--- a/src/tiled/id.h
+++ b/src/tiled/id.h
@@ -23,7 +23,6 @@
 #include <QLatin1String>
 
 namespace Tiled {
-namespace Internal {
 
 class Id
 {
@@ -47,5 +46,4 @@ inline uint qHash(Id id) Q_DECL_NOTHROW
     return id.mId;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/imagecolorpickerwidget.cpp b/src/tiled/imagecolorpickerwidget.cpp
index d9f9c98d76..03e8c5e623 100644
--- a/src/tiled/imagecolorpickerwidget.cpp
+++ b/src/tiled/imagecolorpickerwidget.cpp
@@ -28,7 +28,6 @@
 #include <QMouseEvent>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ImageColorPickerWidget::ImageColorPickerWidget(QWidget *parent) :
     QFrame(parent, Qt::Popup),
diff --git a/src/tiled/imagecolorpickerwidget.h b/src/tiled/imagecolorpickerwidget.h
index 04b5342a5a..7ae4ceac1d 100644
--- a/src/tiled/imagecolorpickerwidget.h
+++ b/src/tiled/imagecolorpickerwidget.h
@@ -30,7 +30,6 @@ class ImageColorPickerWidget;
 }
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A popup widget for selecting a colour from an image.
@@ -64,5 +63,4 @@ private slots:
     void onMouseRelease(QMouseEvent*);
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/imagecolorpickerwidget.ui b/src/tiled/imagecolorpickerwidget.ui
index 4b337e9590..b062c33503 100644
--- a/src/tiled/imagecolorpickerwidget.ui
+++ b/src/tiled/imagecolorpickerwidget.ui
@@ -48,7 +48,7 @@
     <number>5</number>
    </property>
    <item>
-    <widget class="Tiled::Internal::ClickableLabel" name="imageArea">
+    <widget class="Tiled::ClickableLabel" name="imageArea">
      <property name="sizePolicy">
       <sizepolicy hsizetype="Preferred" vsizetype="Expanding">
        <horstretch>0</horstretch>
@@ -119,7 +119,7 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>Tiled::Internal::ClickableLabel</class>
+   <class>Tiled::ClickableLabel</class>
    <extends>QLabel</extends>
    <header>clickablelabel.h</header>
   </customwidget>
diff --git a/src/tiled/imagelayeritem.cpp b/src/tiled/imagelayeritem.cpp
index 2e298328f7..d2ddef5333 100644
--- a/src/tiled/imagelayeritem.cpp
+++ b/src/tiled/imagelayeritem.cpp
@@ -28,7 +28,6 @@
 #include <QStyleOptionGraphicsItem>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ImageLayerItem::ImageLayerItem(ImageLayer *layer, MapDocument *mapDocument, QGraphicsItem *parent)
     : LayerItem(layer, parent)
diff --git a/src/tiled/imagelayeritem.h b/src/tiled/imagelayeritem.h
index 1b65e7aa43..49c1d4c1a9 100644
--- a/src/tiled/imagelayeritem.h
+++ b/src/tiled/imagelayeritem.h
@@ -26,7 +26,6 @@
 #include "imagelayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -72,5 +71,4 @@ inline ImageLayer *ImageLayerItem::imageLayer() const
     return static_cast<ImageLayer*>(layer());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/languagemanager.cpp b/src/tiled/languagemanager.cpp
index afdaa89bb4..0f06bf322e 100644
--- a/src/tiled/languagemanager.cpp
+++ b/src/tiled/languagemanager.cpp
@@ -29,7 +29,7 @@
 #include <QLocale>
 #include <QTranslator>
 
-using namespace Tiled::Internal;
+using namespace Tiled;
 
 LanguageManager *LanguageManager::mInstance;
 
diff --git a/src/tiled/languagemanager.h b/src/tiled/languagemanager.h
index 8dd5f527c7..ada2668661 100644
--- a/src/tiled/languagemanager.h
+++ b/src/tiled/languagemanager.h
@@ -25,7 +25,6 @@
 class QTranslator;
 
 namespace Tiled {
-namespace Internal {
 
 class LanguageManager
 {
@@ -58,5 +57,4 @@ class LanguageManager
     static LanguageManager *mInstance;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/layerdock.cpp b/src/tiled/layerdock.cpp
index a226868cfd..a9a8b7c416 100644
--- a/src/tiled/layerdock.cpp
+++ b/src/tiled/layerdock.cpp
@@ -49,7 +49,6 @@
 #include <QMetaEnum>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 LayerDock::LayerDock(QWidget *parent):
     QDockWidget(parent),
diff --git a/src/tiled/layerdock.h b/src/tiled/layerdock.h
index 2d895a9f38..e346f39d8e 100644
--- a/src/tiled/layerdock.h
+++ b/src/tiled/layerdock.h
@@ -33,7 +33,6 @@ class QModelIndex;
 class QUndoStack;
 
 namespace Tiled {
-namespace Internal {
 
 class LayerView;
 
@@ -112,5 +111,4 @@ private slots:
     bool mUpdatingSelectedLayers;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/layeritem.cpp b/src/tiled/layeritem.cpp
index 5fecbd11c6..ef171d5248 100644
--- a/src/tiled/layeritem.cpp
+++ b/src/tiled/layeritem.cpp
@@ -23,7 +23,6 @@
 #include "layer.h"
 
 namespace Tiled {
-namespace Internal {
 
 LayerItem::LayerItem(Layer *layer, QGraphicsItem *parent)
     : QGraphicsItem(parent)
@@ -34,5 +33,4 @@ LayerItem::LayerItem(Layer *layer, QGraphicsItem *parent)
     setPos(layer->offset());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/layeritem.h b/src/tiled/layeritem.h
index 9602a4dfc0..0d737b59d3 100644
--- a/src/tiled/layeritem.h
+++ b/src/tiled/layeritem.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class LayerItem : public QGraphicsItem
 {
 public:
@@ -39,5 +37,4 @@ class LayerItem : public QGraphicsItem
     Layer *mLayer;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/layermodel.cpp b/src/tiled/layermodel.cpp
index a70c009604..207d5f1ebb 100644
--- a/src/tiled/layermodel.cpp
+++ b/src/tiled/layermodel.cpp
@@ -34,7 +34,6 @@
 #include <QStyle>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 LayerModel::LayerModel(QObject *parent):
     QAbstractItemModel(parent),
diff --git a/src/tiled/layermodel.h b/src/tiled/layermodel.h
index f1fb2f86ab..0150212a3a 100644
--- a/src/tiled/layermodel.h
+++ b/src/tiled/layermodel.h
@@ -29,8 +29,6 @@ class GroupLayer;
 class Layer;
 class Map;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -119,5 +117,4 @@ inline MapDocument *LayerModel::mapDocument() const
     return mMapDocument;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/layeroffsettool.cpp b/src/tiled/layeroffsettool.cpp
index 5ec42b23aa..95d036da9d 100644
--- a/src/tiled/layeroffsettool.cpp
+++ b/src/tiled/layeroffsettool.cpp
@@ -37,7 +37,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 LayerOffsetTool::LayerOffsetTool(QObject *parent)
     : AbstractTool(tr("Offset Layers"),
diff --git a/src/tiled/layeroffsettool.h b/src/tiled/layeroffsettool.h
index dcead941dc..e75df936d0 100644
--- a/src/tiled/layeroffsettool.h
+++ b/src/tiled/layeroffsettool.h
@@ -24,7 +24,6 @@
 #include "abstracttool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class LayerOffsetTool : public AbstractTool
 {
@@ -71,5 +70,4 @@ protected slots:
     QVector<DraggingLayer> mDraggingLayers;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/macsupport.h b/src/tiled/macsupport.h
index 99187772e2..d74a77810c 100644
--- a/src/tiled/macsupport.h
+++ b/src/tiled/macsupport.h
@@ -33,5 +33,5 @@ class MacSupport
     /**
      * Adds fullscreen button to window for Lion.
      */
-    static void addFullscreen(Tiled::Internal::MainWindow *window);
+    static void addFullscreen(Tiled::MainWindow *window);
 };
diff --git a/src/tiled/macsupport.mm b/src/tiled/macsupport.mm
index 351c23b78e..f906159756 100644
--- a/src/tiled/macsupport.mm
+++ b/src/tiled/macsupport.mm
@@ -31,7 +31,7 @@
     return [string respondsToSelector:@selector(linguisticTagsInRange:scheme:options:orthography:tokenRanges:)];
 }
 
-void MacSupport::addFullscreen(Tiled::Internal::MainWindow *window)
+void MacSupport::addFullscreen(Tiled::MainWindow *window)
 {
 #if defined(MAC_OS_X_VERSION_10_7) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
     if (isLion()) // checks if lion is running
diff --git a/src/tiled/magicwandtool.cpp b/src/tiled/magicwandtool.cpp
index 2b8edf393a..c74d2db878 100644
--- a/src/tiled/magicwandtool.cpp
+++ b/src/tiled/magicwandtool.cpp
@@ -27,7 +27,6 @@
 #include "tilepainter.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MagicWandTool::MagicWandTool(QObject *parent)
     : AbstractTileSelectionTool(tr("Magic Wand"),
diff --git a/src/tiled/magicwandtool.h b/src/tiled/magicwandtool.h
index c98edb2605..c69c058169 100644
--- a/src/tiled/magicwandtool.h
+++ b/src/tiled/magicwandtool.h
@@ -29,7 +29,6 @@
 #include "tilelayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -49,5 +48,4 @@ class MagicWandTool : public AbstractTileSelectionTool
     void tilePositionChanged(const QPoint &tilePos) override;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/main.cpp b/src/tiled/main.cpp
index 6088073f5c..186a81f9c2 100644
--- a/src/tiled/main.cpp
+++ b/src/tiled/main.cpp
@@ -57,7 +57,6 @@
 #define AS_STRING(x) STRINGIFY(x)
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace {
 
diff --git a/src/tiled/maintoolbar.cpp b/src/tiled/maintoolbar.cpp
index 96edb5abc6..e8292c6f34 100644
--- a/src/tiled/maintoolbar.cpp
+++ b/src/tiled/maintoolbar.cpp
@@ -32,7 +32,6 @@
 #include <QUndoGroup>
 
 namespace Tiled {
-namespace Internal {
 
 MainToolBar::MainToolBar(QWidget *parent)
     : QToolBar(parent)
@@ -138,5 +137,4 @@ void MainToolBar::retranslateUi()
     mUndoAction->setIconText(tr("Undo"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/maintoolbar.h b/src/tiled/maintoolbar.h
index 6b44b2450b..70bb297c86 100644
--- a/src/tiled/maintoolbar.h
+++ b/src/tiled/maintoolbar.h
@@ -25,7 +25,6 @@
 class QToolButton;
 
 namespace Tiled {
-namespace Internal {
 
 class CommandButton;
 class Document;
@@ -56,5 +55,4 @@ private slots:
     CommandButton *mCommandButton;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mainwindow.cpp b/src/tiled/mainwindow.cpp
index 8b27b980d8..36f2fb657a 100644
--- a/src/tiled/mainwindow.cpp
+++ b/src/tiled/mainwindow.cpp
@@ -98,7 +98,6 @@
 #endif
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 using namespace Tiled::Utils;
 
 
diff --git a/src/tiled/mainwindow.h b/src/tiled/mainwindow.h
index cfc7298db0..1719c47c4f 100644
--- a/src/tiled/mainwindow.h
+++ b/src/tiled/mainwindow.h
@@ -47,8 +47,6 @@ class FileFormat;
 class TileLayer;
 class Terrain;
 
-namespace Internal {
-
 class ActionManager;
 class AutomappingManager;
 class DocumentManager;
@@ -223,5 +221,4 @@ private slots:
     QMap<QMainWindow*, QByteArray> mMainWindowStates;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapdocument.cpp b/src/tiled/mapdocument.cpp
index 915eb630ac..6b3eb29792 100644
--- a/src/tiled/mapdocument.cpp
+++ b/src/tiled/mapdocument.cpp
@@ -67,7 +67,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MapDocument::MapDocument(Map *map, const QString &fileName)
     : Document(MapDocumentType, fileName)
diff --git a/src/tiled/mapdocument.h b/src/tiled/mapdocument.h
index 7cf173ee36..c51b0509c6 100644
--- a/src/tiled/mapdocument.h
+++ b/src/tiled/mapdocument.h
@@ -51,8 +51,6 @@ class Terrain;
 class Tile;
 class WangSet;
 
-namespace Internal {
-
 class LayerModel;
 class MapDocument;
 class MapObjectModel;
@@ -121,7 +119,7 @@ class MapDocument : public Document
      */
     Map *map() const { return mMap.get(); }
 
-    Q_INVOKABLE Tiled::Internal::EditableAsset *editable() override;
+    Q_INVOKABLE Tiled::EditableAsset *editable() override;
 
     int layerIndex(const Layer *layer) const;
 
@@ -381,7 +379,6 @@ public slots:
     bool mAllowTileObjects = true;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_OPERATORS_FOR_FLAGS(Tiled::Internal::MapDocument::TileLayerChangeFlags)
+Q_DECLARE_OPERATORS_FOR_FLAGS(Tiled::MapDocument::TileLayerChangeFlags)
diff --git a/src/tiled/mapdocumentactionhandler.cpp b/src/tiled/mapdocumentactionhandler.cpp
index e06e690785..f9258b51f9 100644
--- a/src/tiled/mapdocumentactionhandler.cpp
+++ b/src/tiled/mapdocumentactionhandler.cpp
@@ -52,7 +52,6 @@
 #include <algorithm>
 
 namespace Tiled {
-namespace Internal {
 
 MapDocumentActionHandler *MapDocumentActionHandler::mInstance;
 
@@ -821,5 +820,4 @@ void MapDocumentActionHandler::updateActions()
     mActionRemoveObjects->setText(removeText);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapdocumentactionhandler.h b/src/tiled/mapdocumentactionhandler.h
index f0157dadd3..1aeaaeaec8 100644
--- a/src/tiled/mapdocumentactionhandler.h
+++ b/src/tiled/mapdocumentactionhandler.h
@@ -32,8 +32,6 @@ namespace Tiled {
 class ObjectGroup;
 class MapObject;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -174,5 +172,4 @@ private slots:
     static MapDocumentActionHandler *mInstance;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapeditor.cpp b/src/tiled/mapeditor.cpp
index f8a82de748..1c6a5e1568 100644
--- a/src/tiled/mapeditor.cpp
+++ b/src/tiled/mapeditor.cpp
@@ -101,7 +101,6 @@ static const char STATE_KEY[] = "MapEditor/State";
 static const char MAPSTATES_KEY[] = "MapEditor/MapStates";
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A proxy model that makes sure no items are checked or checkable and that
@@ -932,5 +931,4 @@ void MapEditor::retranslateUi()
     mToolSpecificToolBar->setWindowTitle(tr("Tool Options"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapeditor.h b/src/tiled/mapeditor.h
index 9e35826062..2a7f263a57 100644
--- a/src/tiled/mapeditor.h
+++ b/src/tiled/mapeditor.h
@@ -40,8 +40,6 @@ namespace Tiled {
 
 class Terrain;
 
-namespace Internal {
-
 class AbstractTool;
 class BucketFillTool;
 class ComboBoxProxyModel;
@@ -194,5 +192,4 @@ inline MapView *MapEditor::currentMapView() const
     return viewForDocument(mCurrentMapDocument);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapitem.cpp b/src/tiled/mapitem.cpp
index da6c9d03c3..0861e1c527 100644
--- a/src/tiled/mapitem.cpp
+++ b/src/tiled/mapitem.cpp
@@ -45,7 +45,6 @@
 #include "qtcompat_p.h"
 
 namespace Tiled {
-namespace Internal {
 
 static const qreal darkeningFactor = 0.6;
 static const qreal opacityFactor = 0.4;
@@ -678,7 +677,6 @@ void MapItem::updateSelectedLayersHighlight()
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
 
 #include "mapitem.moc"
diff --git a/src/tiled/mapitem.h b/src/tiled/mapitem.h
index c44af3cc85..57dc855ed0 100644
--- a/src/tiled/mapitem.h
+++ b/src/tiled/mapitem.h
@@ -37,8 +37,6 @@ class Tile;
 class TileLayer;
 class Tileset;
 
-namespace Internal {
-
 class BorderItem;
 class LayerItem;
 class MapObjectItem;
@@ -140,5 +138,4 @@ inline MapDocument *MapItem::mapDocument() const
     return mMapDocument.data();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapobjectitem.cpp b/src/tiled/mapobjectitem.cpp
index eef0de949c..5c59759f1f 100644
--- a/src/tiled/mapobjectitem.cpp
+++ b/src/tiled/mapobjectitem.cpp
@@ -39,7 +39,6 @@
 #include <cmath>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MapObjectItem::MapObjectItem(MapObject *object, MapDocument *mapDocument,
                              QGraphicsItem *parent):
diff --git a/src/tiled/mapobjectitem.h b/src/tiled/mapobjectitem.h
index 0fd918d3e9..3a08b2f7a0 100644
--- a/src/tiled/mapobjectitem.h
+++ b/src/tiled/mapobjectitem.h
@@ -28,8 +28,6 @@ namespace Tiled {
 
 class MapObject;
 
-namespace Internal {
-
 class Handle;
 class MapDocument;
 class ObjectGroupItem;
@@ -112,7 +110,6 @@ inline bool MapObjectItem::isHoverIndicator() const
     return mIsHoveredIndicator;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::MapObjectItem*)
+Q_DECLARE_METATYPE(Tiled::MapObjectItem*)
diff --git a/src/tiled/mapobjectmodel.cpp b/src/tiled/mapobjectmodel.cpp
index 28de43936a..9a6c7edb98 100644
--- a/src/tiled/mapobjectmodel.cpp
+++ b/src/tiled/mapobjectmodel.cpp
@@ -35,7 +35,6 @@
 #include <QStyle>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MapObjectModel::MapObjectModel(QObject *parent):
     QAbstractItemModel(parent),
diff --git a/src/tiled/mapobjectmodel.h b/src/tiled/mapobjectmodel.h
index 8d640d4940..854b176229 100644
--- a/src/tiled/mapobjectmodel.h
+++ b/src/tiled/mapobjectmodel.h
@@ -34,8 +34,6 @@ class MapObject;
 class Map;
 class ObjectGroup;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -126,5 +124,4 @@ private slots:
     QIcon mObjectGroupIcon;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapscene.cpp b/src/tiled/mapscene.cpp
index ee6d2bdca2..70af3734bb 100644
--- a/src/tiled/mapscene.cpp
+++ b/src/tiled/mapscene.cpp
@@ -48,7 +48,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MapScene::MapScene(QObject *parent):
     QGraphicsScene(parent),
diff --git a/src/tiled/mapscene.h b/src/tiled/mapscene.h
index 47eca49af9..34d4db08c4 100644
--- a/src/tiled/mapscene.h
+++ b/src/tiled/mapscene.h
@@ -39,8 +39,6 @@ class Tile;
 class TileLayer;
 class Tileset;
 
-namespace Internal {
-
 class AbstractTool;
 class LayerItem;
 class MapDocument;
@@ -121,5 +119,4 @@ inline MapDocument *MapScene::mapDocument() const
     return mMapDocument;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapsdock.cpp b/src/tiled/mapsdock.cpp
index b1c1f5fcfc..94df5ab673 100644
--- a/src/tiled/mapsdock.cpp
+++ b/src/tiled/mapsdock.cpp
@@ -39,7 +39,6 @@
 #include <QPushButton>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 /**
  * Class represents the file system model with disabled dragging of directories.
diff --git a/src/tiled/mapsdock.h b/src/tiled/mapsdock.h
index ef7fa350ea..5bc8e10a90 100644
--- a/src/tiled/mapsdock.h
+++ b/src/tiled/mapsdock.h
@@ -30,7 +30,6 @@ class QModelIndex;
 class QTreeView;
 
 namespace Tiled {
-namespace Internal {
 
 class MapsView;
 
@@ -87,5 +86,4 @@ private slots:
     QFileSystemModel *mFileSystemModel;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/mapview.cpp b/src/tiled/mapview.cpp
index 8564aeffca..d9a2277b04 100644
--- a/src/tiled/mapview.cpp
+++ b/src/tiled/mapview.cpp
@@ -39,7 +39,6 @@
 #endif
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MapView::MapView(QWidget *parent, Mode mode)
     : QGraphicsView(parent)
diff --git a/src/tiled/mapview.h b/src/tiled/mapview.h
index a55fc320ba..ba1935f779 100644
--- a/src/tiled/mapview.h
+++ b/src/tiled/mapview.h
@@ -24,7 +24,6 @@
 #include <QPinchGesture>
 
 namespace Tiled {
-namespace Internal {
 
 class MapScene;
 class Zoomable;
@@ -104,5 +103,4 @@ private slots:
     Zoomable *mZoomable;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/minimap.cpp b/src/tiled/minimap.cpp
index 56cf87f920..f272e2d582 100644
--- a/src/tiled/minimap.cpp
+++ b/src/tiled/minimap.cpp
@@ -36,7 +36,6 @@
 #include <QUndoStack>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MiniMap::MiniMap(QWidget *parent)
     : QFrame(parent)
diff --git a/src/tiled/minimap.h b/src/tiled/minimap.h
index 4d7dd3a0a3..6c79629257 100644
--- a/src/tiled/minimap.h
+++ b/src/tiled/minimap.h
@@ -28,7 +28,6 @@
 #include <QTimer>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -79,5 +78,4 @@ private slots:
     void centerViewOnLocalPixel(QPoint centerPos, int delta = 0);
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/minimapdock.cpp b/src/tiled/minimapdock.cpp
index 7543b11807..d1117c4970 100644
--- a/src/tiled/minimapdock.cpp
+++ b/src/tiled/minimapdock.cpp
@@ -25,7 +25,6 @@
 #include <QEvent>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MiniMapDock::MiniMapDock(QWidget *parent)
     : QDockWidget(parent)
diff --git a/src/tiled/minimapdock.h b/src/tiled/minimapdock.h
index 4a56b1a6bb..71641d1876 100644
--- a/src/tiled/minimapdock.h
+++ b/src/tiled/minimapdock.h
@@ -23,7 +23,6 @@
 #include <QDockWidget>
 
 namespace Tiled {
-namespace Internal {
 
 class MiniMap;
 class MapDocument;
@@ -49,5 +48,4 @@ class MiniMapDock : public QDockWidget
     MiniMap *mMiniMap;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/minimaprenderer.cpp b/src/tiled/minimaprenderer.cpp
index b51a4b3aaf..4f55b96492 100644
--- a/src/tiled/minimaprenderer.cpp
+++ b/src/tiled/minimaprenderer.cpp
@@ -39,7 +39,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MiniMapRenderer::MiniMapRenderer(Map *map)
     : mMap(map)
diff --git a/src/tiled/minimaprenderer.h b/src/tiled/minimaprenderer.h
index 87f02474a1..79537343a9 100644
--- a/src/tiled/minimaprenderer.h
+++ b/src/tiled/minimaprenderer.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class Map;
 class MapRenderer;
 
-namespace Internal {
-
 class MiniMapRenderer
 {
 public:
@@ -59,7 +57,6 @@ class MiniMapRenderer
     MapRenderer *mRenderer;
 };
 
-Q_DECLARE_OPERATORS_FOR_FLAGS(Tiled::Internal::MiniMapRenderer::RenderFlags)
+Q_DECLARE_OPERATORS_FOR_FLAGS(Tiled::MiniMapRenderer::RenderFlags)
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/movelayer.cpp b/src/tiled/movelayer.cpp
index 7d9fdf9fd9..002b701ddc 100644
--- a/src/tiled/movelayer.cpp
+++ b/src/tiled/movelayer.cpp
@@ -31,7 +31,6 @@
 #include <algorithm>
 
 namespace Tiled {
-namespace Internal {
 
 MoveLayer::MoveLayer(MapDocument *mapDocument, Layer *layer, Direction direction):
     mMapDocument(mapDocument),
@@ -115,4 +114,3 @@ void MoveLayer::moveLayer()
 }
 
 } // namespace Tiled
-} // namespace Internal
diff --git a/src/tiled/movelayer.h b/src/tiled/movelayer.h
index 8217efcaea..afe8cad7cb 100644
--- a/src/tiled/movelayer.h
+++ b/src/tiled/movelayer.h
@@ -27,8 +27,6 @@ namespace Tiled {
 class Layer;
 class Map;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -64,5 +62,4 @@ class MoveLayer : public QUndoCommand
     Direction mDirection;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/movemapobject.cpp b/src/tiled/movemapobject.cpp
index 1eac0a8cb8..44e6916874 100644
--- a/src/tiled/movemapobject.cpp
+++ b/src/tiled/movemapobject.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MoveMapObject::MoveMapObject(MapDocument *mapDocument,
                              MapObject *mapObject,
diff --git a/src/tiled/movemapobject.h b/src/tiled/movemapobject.h
index aba253a545..ba4855294c 100644
--- a/src/tiled/movemapobject.h
+++ b/src/tiled/movemapobject.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class MapObject;
 
-namespace Internal {
-
 class MapDocument;
 
 class MoveMapObject : public QUndoCommand
@@ -55,5 +53,4 @@ class MoveMapObject : public QUndoCommand
     QPointF mNewPos;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/movemapobjecttogroup.cpp b/src/tiled/movemapobjecttogroup.cpp
index d9d31c8cbf..a764d61d8e 100644
--- a/src/tiled/movemapobjecttogroup.cpp
+++ b/src/tiled/movemapobjecttogroup.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MoveMapObjectToGroup::MoveMapObjectToGroup(MapDocument *mapDocument,
                                            MapObject *mapObject,
diff --git a/src/tiled/movemapobjecttogroup.h b/src/tiled/movemapobjecttogroup.h
index 8bd59ed539..8563caaf13 100644
--- a/src/tiled/movemapobjecttogroup.h
+++ b/src/tiled/movemapobjecttogroup.h
@@ -27,8 +27,6 @@ namespace Tiled {
 class MapObject;
 class ObjectGroup;
 
-namespace Internal {
-
 class MapDocument;
 
 class MoveMapObjectToGroup : public QUndoCommand
@@ -49,5 +47,4 @@ class MoveMapObjectToGroup : public QUndoCommand
     int mOldIndex;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/moveterrain.cpp b/src/tiled/moveterrain.cpp
index fd85f8914f..9e6eeeaeff 100644
--- a/src/tiled/moveterrain.cpp
+++ b/src/tiled/moveterrain.cpp
@@ -29,7 +29,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 MoveTerrain::MoveTerrain(TilesetDocument *tilesetDocument, int index)
     : mTilesetDocument(tilesetDocument)
diff --git a/src/tiled/moveterrain.h b/src/tiled/moveterrain.h
index 7104e93d2f..1bd7f59fb8 100644
--- a/src/tiled/moveterrain.h
+++ b/src/tiled/moveterrain.h
@@ -28,8 +28,6 @@ namespace Tiled {
 class Terrain;
 class Tileset;
 
-namespace Internal {
-
 class TilesetDocument;
 
 /**
@@ -77,5 +75,4 @@ class MoveTerrainDown : public MoveTerrain
     void redo() override { moveTerrainDown(); }
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newmapdialog.cpp b/src/tiled/newmapdialog.cpp
index 8b82adc611..afc7519775 100644
--- a/src/tiled/newmapdialog.cpp
+++ b/src/tiled/newmapdialog.cpp
@@ -45,7 +45,6 @@ static const char * const TILE_WIDTH_KEY = "Map/TileWidth";
 static const char * const TILE_HEIGHT_KEY = "Map/TileHeight";
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 template<typename Type>
 static Type comboBoxValue(QComboBox *comboBox)
diff --git a/src/tiled/newmapdialog.h b/src/tiled/newmapdialog.h
index ec0cc72b92..e5fc11c4d1 100644
--- a/src/tiled/newmapdialog.h
+++ b/src/tiled/newmapdialog.h
@@ -29,7 +29,6 @@ class NewMapDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A dialog for the creation of a new map.
@@ -57,5 +56,4 @@ private slots:
     Ui::NewMapDialog *mUi;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newsbutton.cpp b/src/tiled/newsbutton.cpp
index 81e713b74b..b59856f7e7 100644
--- a/src/tiled/newsbutton.cpp
+++ b/src/tiled/newsbutton.cpp
@@ -30,7 +30,6 @@
 static const char newsArchiveUrl[] = "https://www.mapeditor.org/news";
 
 namespace Tiled {
-namespace Internal {
 
 NewsButton::NewsButton(QWidget *parent)
     : QToolButton(parent)
@@ -125,5 +124,4 @@ void NewsButton::showNewsMenu()
     setDown(false);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newsbutton.h b/src/tiled/newsbutton.h
index 186fb0d344..c155505fbd 100644
--- a/src/tiled/newsbutton.h
+++ b/src/tiled/newsbutton.h
@@ -23,7 +23,6 @@
 #include <QToolButton>
 
 namespace Tiled {
-namespace Internal {
 
 class NewsButton : public QToolButton
 {
@@ -40,5 +39,4 @@ class NewsButton : public QToolButton
     QIcon mUnreadIcon;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newsfeed.cpp b/src/tiled/newsfeed.cpp
index 2e2e12b912..6e7a5cde83 100644
--- a/src/tiled/newsfeed.cpp
+++ b/src/tiled/newsfeed.cpp
@@ -32,7 +32,6 @@
 static const char feedUrl[] = "https://www.mapeditor.org/rss.xml";
 
 namespace Tiled {
-namespace Internal {
 
 NewsFeed::NewsFeed()
     : mNetworkAccessManager(new QNetworkAccessManager(this))
@@ -175,5 +174,4 @@ void NewsFeed::setLastRead(const QDateTime &dateTime)
     emit refreshed();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newsfeed.h b/src/tiled/newsfeed.h
index 81912b97ba..6dc4b441aa 100644
--- a/src/tiled/newsfeed.h
+++ b/src/tiled/newsfeed.h
@@ -31,7 +31,6 @@ class QNetworkAccessManager;
 class QNetworkReply;
 
 namespace Tiled {
-namespace Internal {
 
 class NewsItem
 {
@@ -105,5 +104,4 @@ inline QString NewsFeed::errorString() const
     return mErrorString;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newtilesetdialog.cpp b/src/tiled/newtilesetdialog.cpp
index 4629ab449c..70402f685c 100644
--- a/src/tiled/newtilesetdialog.cpp
+++ b/src/tiled/newtilesetdialog.cpp
@@ -43,7 +43,6 @@ static const char * const SPACING_KEY = "Tileset/Spacing";
 static const char * const MARGIN_KEY = "Tileset/Margin";
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 enum TilesetType {
     TilesetImage,
diff --git a/src/tiled/newtilesetdialog.h b/src/tiled/newtilesetdialog.h
index 7177b949dc..9d1ee0523b 100644
--- a/src/tiled/newtilesetdialog.h
+++ b/src/tiled/newtilesetdialog.h
@@ -30,7 +30,6 @@ class NewTilesetDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A dialog for the creation of a new tileset, or for editing the parameters
@@ -78,5 +77,4 @@ private slots:
     SharedTileset mNewTileset;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/newtilesetdialog.ui b/src/tiled/newtilesetdialog.ui
index 1eae62d6ad..a1947dacf4 100644
--- a/src/tiled/newtilesetdialog.ui
+++ b/src/tiled/newtilesetdialog.ui
@@ -142,7 +142,7 @@
        </widget>
       </item>
       <item row="1" column="2">
-       <widget class="Tiled::Internal::ColorButton" name="colorButton">
+       <widget class="Tiled::ColorButton" name="colorButton">
         <property name="enabled">
          <bool>false</bool>
         </property>
@@ -332,7 +332,7 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>Tiled::Internal::ColorButton</class>
+   <class>Tiled::ColorButton</class>
    <extends>QToolButton</extends>
    <header>colorbutton.h</header>
   </customwidget>
diff --git a/src/tiled/noeditorwidget.cpp b/src/tiled/noeditorwidget.cpp
index 0ceb07a317..aa10d8c475 100644
--- a/src/tiled/noeditorwidget.cpp
+++ b/src/tiled/noeditorwidget.cpp
@@ -27,7 +27,6 @@
 #include <QAction>
 
 namespace Tiled {
-namespace Internal {
 
 NoEditorWidget::NoEditorWidget(QWidget *parent) :
     QWidget(parent),
@@ -72,5 +71,4 @@ void NoEditorWidget::openFile()
     DocumentManager::instance()->openFileDialog();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/noeditorwidget.h b/src/tiled/noeditorwidget.h
index df39b6d6df..9302340622 100644
--- a/src/tiled/noeditorwidget.h
+++ b/src/tiled/noeditorwidget.h
@@ -23,7 +23,6 @@
 #include <QWidget>
 
 namespace Tiled {
-namespace Internal {
 
 namespace Ui {
 class NoEditorWidget;
@@ -49,5 +48,4 @@ private slots:
     Ui::NoEditorWidget *ui;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/noeditorwidget.ui b/src/tiled/noeditorwidget.ui
index 290aab156c..11479d5570 100644
--- a/src/tiled/noeditorwidget.ui
+++ b/src/tiled/noeditorwidget.ui
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <ui version="4.0">
- <class>Tiled::Internal::NoEditorWidget</class>
- <widget class="QWidget" name="Tiled::Internal::NoEditorWidget">
+ <class>Tiled::NoEditorWidget</class>
+ <widget class="QWidget" name="Tiled::NoEditorWidget">
   <property name="geometry">
    <rect>
     <x>0</x>
diff --git a/src/tiled/objectgroupitem.cpp b/src/tiled/objectgroupitem.cpp
index d9f1747c15..032bbe22c6 100644
--- a/src/tiled/objectgroupitem.cpp
+++ b/src/tiled/objectgroupitem.cpp
@@ -21,7 +21,6 @@
 #include "objectgroupitem.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ObjectGroupItem::ObjectGroupItem(ObjectGroup *objectGroup, QGraphicsItem *parent)
     : LayerItem(objectGroup, parent)
diff --git a/src/tiled/objectgroupitem.h b/src/tiled/objectgroupitem.h
index 19842b998a..7fb6492e3e 100644
--- a/src/tiled/objectgroupitem.h
+++ b/src/tiled/objectgroupitem.h
@@ -25,7 +25,6 @@
 #include "objectgroup.h"
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A graphics item representing an object group in a QGraphicsView. It only
@@ -52,5 +51,4 @@ inline ObjectGroup *ObjectGroupItem::objectGroup() const
     return static_cast<ObjectGroup*>(layer());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objectsdock.cpp b/src/tiled/objectsdock.cpp
index 7d66b1ea45..47505aafe9 100644
--- a/src/tiled/objectsdock.cpp
+++ b/src/tiled/objectsdock.cpp
@@ -49,7 +49,6 @@ static const char FIRST_COLUMN_WIDTH_KEY[] = "ObjectsDock/FirstSectionSize";
 static const char VISIBLE_COLUMNS_KEY[] = "ObjectsDock/VisibleSections";
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ObjectsDock::ObjectsDock(QWidget *parent)
     : QDockWidget(parent)
diff --git a/src/tiled/objectsdock.h b/src/tiled/objectsdock.h
index 4d1e9e9de0..303ee7b662 100644
--- a/src/tiled/objectsdock.h
+++ b/src/tiled/objectsdock.h
@@ -31,8 +31,6 @@ namespace Tiled {
 class Layer;
 class MapObject;
 
-namespace Internal {
-
 class Document;
 class MapDocument;
 class MapObjectModel;
@@ -122,5 +120,4 @@ private slots:
     bool mSynching;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objectselectionitem.cpp b/src/tiled/objectselectionitem.cpp
index 9a90a28d01..97a4a2f6dd 100644
--- a/src/tiled/objectselectionitem.cpp
+++ b/src/tiled/objectselectionitem.cpp
@@ -40,7 +40,6 @@
 #include <cmath>
 
 namespace Tiled {
-namespace Internal {
 
 static const qreal labelMargin = 2;
 static const qreal labelDistance = 4;
@@ -551,5 +550,4 @@ void ObjectSelectionItem::addRemoveObjectOutlines()
     mObjectOutlines.swap(outlineItems);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objectselectionitem.h b/src/tiled/objectselectionitem.h
index 0ac6c5e1e1..c619c2b1c1 100644
--- a/src/tiled/objectselectionitem.h
+++ b/src/tiled/objectselectionitem.h
@@ -32,8 +32,6 @@ class Layer;
 class MapObject;
 class Tile;
 
-namespace Internal {
-
 class MapDocument;
 class MapObjectItem;
 class MapObjectLabel;
@@ -83,5 +81,4 @@ private slots:
     std::unique_ptr<MapObjectItem> mHoveredMapObjectItem;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objectselectiontool.cpp b/src/tiled/objectselectiontool.cpp
index fb8b27daf8..9086197c4a 100644
--- a/src/tiled/objectselectiontool.cpp
+++ b/src/tiled/objectselectiontool.cpp
@@ -58,10 +58,8 @@
 #include <float.h>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace Tiled {
-namespace Internal {
 
 enum AnchorPosition {
     TopLeftAnchor,
@@ -309,7 +307,6 @@ void ResizeHandle::paint(QPainter *painter,
     painter->drawPath(mArrow);
 }
 
-} // namespace Internal
 } // namespace Tiled
 
 
diff --git a/src/tiled/objectselectiontool.h b/src/tiled/objectselectiontool.h
index b09a6eb995..f6201cc350 100644
--- a/src/tiled/objectselectiontool.h
+++ b/src/tiled/objectselectiontool.h
@@ -31,7 +31,6 @@
 class QGraphicsItem;
 
 namespace Tiled {
-namespace Internal {
 
 class Handle;
 class OriginIndicator;
@@ -166,5 +165,4 @@ private slots:
     Qt::KeyboardModifiers mModifiers;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objecttemplatemodel.cpp b/src/tiled/objecttemplatemodel.cpp
index 5ec967d483..90f86923d0 100644
--- a/src/tiled/objecttemplatemodel.cpp
+++ b/src/tiled/objecttemplatemodel.cpp
@@ -30,7 +30,6 @@
 #include <QMimeData>
 
 namespace Tiled {
-namespace Internal {
 
 ObjectTemplateModel::ObjectTemplateModel(QObject *parent):
     QFileSystemModel(parent)
@@ -121,5 +120,4 @@ void ObjectTemplateModel::updateNameFilters()
     setNameFilters(nameFilters);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objecttemplatemodel.h b/src/tiled/objecttemplatemodel.h
index 54490a6ae1..568547f044 100644
--- a/src/tiled/objecttemplatemodel.h
+++ b/src/tiled/objecttemplatemodel.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class ObjectTemplate;
 
-namespace Internal {
-
 class ObjectTemplateModel : public QFileSystemModel
 {
     Q_OBJECT
@@ -51,5 +49,4 @@ private slots:
     void updateNameFilters();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objecttypeseditor.cpp b/src/tiled/objecttypeseditor.cpp
index 114e534659..2a34cc8439 100644
--- a/src/tiled/objecttypeseditor.cpp
+++ b/src/tiled/objecttypeseditor.cpp
@@ -39,7 +39,6 @@
 #include <QToolBar>
 
 namespace Tiled {
-namespace Internal {
 
 class ColorDelegate : public QStyledItemDelegate
 {
@@ -600,5 +599,4 @@ void ObjectTypesEditor::currentItemChanged(QtBrowserItem *item)
     mRenamePropertyAction->setEnabled(itemSelected);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objecttypeseditor.h b/src/tiled/objecttypeseditor.h
index 65803db0bf..0ae6eb2e09 100644
--- a/src/tiled/objecttypeseditor.h
+++ b/src/tiled/objecttypeseditor.h
@@ -35,7 +35,6 @@ class QtVariantProperty;
 class QtVariantPropertyManager;
 
 namespace Tiled {
-namespace Internal {
 
 class ObjectTypesModel;
 
@@ -104,5 +103,4 @@ private slots:
     QAction *mRenamePropertyAction;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/objecttypesmodel.cpp b/src/tiled/objecttypesmodel.cpp
index b81c79e8e0..52d54d9290 100644
--- a/src/tiled/objecttypesmodel.cpp
+++ b/src/tiled/objecttypesmodel.cpp
@@ -21,7 +21,6 @@
 #include "objecttypesmodel.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 static bool objectTypeLessThan(const ObjectType &a, const ObjectType &b)
 {
diff --git a/src/tiled/objecttypesmodel.h b/src/tiled/objecttypesmodel.h
index 6ee3281206..c6697199e0 100644
--- a/src/tiled/objecttypesmodel.h
+++ b/src/tiled/objecttypesmodel.h
@@ -26,7 +26,6 @@
 #include <QAbstractTableModel>
 
 namespace Tiled {
-namespace Internal {
 
 class ObjectTypesModel : public QAbstractTableModel
 {
@@ -65,5 +64,4 @@ public slots:
     ObjectTypes mObjectTypes;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/offsetlayer.cpp b/src/tiled/offsetlayer.cpp
index 873a455c47..09ed412d9b 100644
--- a/src/tiled/offsetlayer.cpp
+++ b/src/tiled/offsetlayer.cpp
@@ -34,7 +34,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 /**
  * Creates an undo command that offsets the layer at \a index by \a offset,
diff --git a/src/tiled/offsetlayer.h b/src/tiled/offsetlayer.h
index 1bcacc868f..5d52cb6a54 100644
--- a/src/tiled/offsetlayer.h
+++ b/src/tiled/offsetlayer.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -60,5 +58,4 @@ class OffsetLayer : public QUndoCommand
     QPointF mNewOffset;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/offsetmapdialog.cpp b/src/tiled/offsetmapdialog.cpp
index 0bcb2f959e..23261991ff 100644
--- a/src/tiled/offsetmapdialog.cpp
+++ b/src/tiled/offsetmapdialog.cpp
@@ -27,7 +27,6 @@
 #include "ui_offsetmapdialog.h"
 
 namespace Tiled {
-namespace Internal {
 
 OffsetMapDialog::OffsetMapDialog(MapDocument *mapDocument, QWidget *parent)
     : QDialog(parent)
@@ -176,5 +175,4 @@ void OffsetMapDialog::boundsSelectionChanged()
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/offsetmapdialog.h b/src/tiled/offsetmapdialog.h
index c06612d9ee..c2f5b86509 100644
--- a/src/tiled/offsetmapdialog.h
+++ b/src/tiled/offsetmapdialog.h
@@ -31,8 +31,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 class OffsetMapDialog : public QDialog
@@ -75,5 +73,4 @@ private slots:
     MapDocument *mMapDocument;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/painttilelayer.cpp b/src/tiled/painttilelayer.cpp
index 0be1abef29..67140f236d 100644
--- a/src/tiled/painttilelayer.cpp
+++ b/src/tiled/painttilelayer.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 PaintTileLayer::PaintTileLayer(MapDocument *mapDocument,
                                TileLayer *target,
diff --git a/src/tiled/painttilelayer.h b/src/tiled/painttilelayer.h
index fe8358d205..3a64aebe74 100644
--- a/src/tiled/painttilelayer.h
+++ b/src/tiled/painttilelayer.h
@@ -30,8 +30,6 @@ namespace Tiled {
 
 class TileLayer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -109,5 +107,4 @@ inline void PaintTileLayer::setMergeable(bool mergeable)
     mMergeable = mergeable;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/patreondialog.cpp b/src/tiled/patreondialog.cpp
index f9a63d9ee6..a089b6e8d8 100644
--- a/src/tiled/patreondialog.cpp
+++ b/src/tiled/patreondialog.cpp
@@ -29,7 +29,7 @@
 #include <QUrl>
 #include <QMenu>
 
-using namespace Tiled::Internal;
+using namespace Tiled;
 
 PatreonDialog::PatreonDialog(QWidget *parent) :
     QDialog(parent),
diff --git a/src/tiled/patreondialog.h b/src/tiled/patreondialog.h
index d3b2f8c199..b680f5b04d 100644
--- a/src/tiled/patreondialog.h
+++ b/src/tiled/patreondialog.h
@@ -27,7 +27,6 @@ class PatreonDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 class PatreonDialog : public QDialog
 {
@@ -46,5 +45,4 @@ private slots:
     Ui::PatreonDialog *ui;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/pluginlistmodel.cpp b/src/tiled/pluginlistmodel.cpp
index 6931d4a901..209a963dd8 100644
--- a/src/tiled/pluginlistmodel.cpp
+++ b/src/tiled/pluginlistmodel.cpp
@@ -26,7 +26,6 @@
 #include <QIcon>
 
 namespace Tiled {
-namespace Internal {
 
 PluginListModel::PluginListModel(QObject *parent)
     : QAbstractListModel(parent)
@@ -110,6 +109,5 @@ bool PluginListModel::setData(const QModelIndex &index, const QVariant &value, i
     return false;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
diff --git a/src/tiled/pluginlistmodel.h b/src/tiled/pluginlistmodel.h
index 6d010613e3..a8d5b2f5dc 100644
--- a/src/tiled/pluginlistmodel.h
+++ b/src/tiled/pluginlistmodel.h
@@ -24,7 +24,6 @@
 #include <QIcon>
 
 namespace Tiled {
-namespace Internal {
 
 class PluginListModel : public QAbstractListModel
 {
@@ -46,5 +45,4 @@ class PluginListModel : public QAbstractListModel
     QIcon mPluginErrorIcon;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/pointhandle.cpp b/src/tiled/pointhandle.cpp
index d100ffec75..269a0553ba 100644
--- a/src/tiled/pointhandle.cpp
+++ b/src/tiled/pointhandle.cpp
@@ -28,7 +28,6 @@
 #include <QPalette>
 
 namespace Tiled {
-namespace Internal {
 
 PointHandle::PointHandle(MapObject *mapObject, int pointIndex)
     : QGraphicsItem()
@@ -88,5 +87,4 @@ void PointHandle::paint(QPainter *painter,
         painter->drawEllipse(QRectF(-4, -4, 8, 8));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/pointhandle.h b/src/tiled/pointhandle.h
index ec6bb9b13b..318360324d 100644
--- a/src/tiled/pointhandle.h
+++ b/src/tiled/pointhandle.h
@@ -27,7 +27,6 @@ namespace Tiled {
 
 class MapObject;
 
-namespace Internal {
 
 /**
  * A handle that allows moving around a point of a polygon.
@@ -63,7 +62,6 @@ class PointHandle : public QGraphicsItem
     bool mHighlighted;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
 #endif // POINTHANDLE_H
diff --git a/src/tiled/preferences.cpp b/src/tiled/preferences.cpp
index f2270292e3..cb1f5b0b8f 100644
--- a/src/tiled/preferences.cpp
+++ b/src/tiled/preferences.cpp
@@ -34,7 +34,6 @@
 #include <QStandardPaths>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 Preferences *Preferences::mInstance;
 
diff --git a/src/tiled/preferences.h b/src/tiled/preferences.h
index 243825cf22..472fa853c1 100644
--- a/src/tiled/preferences.h
+++ b/src/tiled/preferences.h
@@ -31,7 +31,6 @@
 class QSettings;
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * This class holds user preferences and provides a convenient interface to
@@ -392,7 +391,6 @@ inline bool Preferences::wheelZoomsByDefault() const
     return mWheelZoomsByDefault;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_OPERATORS_FOR_FLAGS(Tiled::Internal::Preferences::ExportOptions)
+Q_DECLARE_OPERATORS_FOR_FLAGS(Tiled::Preferences::ExportOptions)
diff --git a/src/tiled/preferencesdialog.cpp b/src/tiled/preferencesdialog.cpp
index b9d6e99318..a831dfe42b 100644
--- a/src/tiled/preferencesdialog.cpp
+++ b/src/tiled/preferencesdialog.cpp
@@ -31,7 +31,6 @@
 #include "qtcompat_p.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 PreferencesDialog::PreferencesDialog(QWidget *parent)
     : QDialog(parent)
diff --git a/src/tiled/preferencesdialog.h b/src/tiled/preferencesdialog.h
index 010036c1f8..f99ac5fb00 100644
--- a/src/tiled/preferencesdialog.h
+++ b/src/tiled/preferencesdialog.h
@@ -29,7 +29,6 @@ class PreferencesDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * The preferences dialog. Allows the user to configure some general behaviour
@@ -64,5 +63,4 @@ private slots:
 };
 
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/preferencesdialog.ui b/src/tiled/preferencesdialog.ui
index db8194bc02..7bcbe85791 100644
--- a/src/tiled/preferencesdialog.ui
+++ b/src/tiled/preferencesdialog.ui
@@ -127,7 +127,7 @@
          </property>
          <layout class="QGridLayout" name="gridLayout_2">
           <item row="2" column="3">
-           <widget class="Tiled::Internal::ColorButton" name="gridColor"/>
+           <widget class="Tiled::ColorButton" name="gridColor"/>
           </item>
           <item row="0" column="4">
            <spacer name="horizontalSpacer_2">
@@ -258,7 +258,7 @@
            </widget>
           </item>
           <item row="2" column="2">
-           <widget class="Tiled::Internal::ColorButton" name="selectionColor"/>
+           <widget class="Tiled::ColorButton" name="selectionColor"/>
           </item>
           <item row="0" column="0">
            <widget class="QLabel" name="label_5">
@@ -271,7 +271,7 @@
            </widget>
           </item>
           <item row="1" column="2">
-           <widget class="Tiled::Internal::ColorButton" name="baseColor"/>
+           <widget class="Tiled::ColorButton" name="baseColor"/>
           </item>
           <item row="0" column="3">
            <spacer name="horizontalSpacer">
@@ -421,7 +421,7 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>Tiled::Internal::ColorButton</class>
+   <class>Tiled::ColorButton</class>
    <extends>QToolButton</extends>
    <header>colorbutton.h</header>
   </customwidget>
diff --git a/src/tiled/propertiesdock.cpp b/src/tiled/propertiesdock.cpp
index fd2f624b1b..5f8f9213bf 100644
--- a/src/tiled/propertiesdock.cpp
+++ b/src/tiled/propertiesdock.cpp
@@ -43,7 +43,6 @@
 #include <QMenu>
 
 namespace Tiled {
-namespace Internal {
 
 PropertiesDock::PropertiesDock(QWidget *parent)
     : QDockWidget(parent)
@@ -493,5 +492,4 @@ void PropertiesDock::retranslateUi()
     mActionRenameProperty->setText(tr("Rename Property"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/propertiesdock.h b/src/tiled/propertiesdock.h
index 8c13762f5d..ed928fd6de 100644
--- a/src/tiled/propertiesdock.h
+++ b/src/tiled/propertiesdock.h
@@ -30,8 +30,6 @@ namespace Tiled {
 class Object;
 class Tileset;
 
-namespace Internal {
-
 class Document;
 class PropertyBrowser;
 
@@ -78,5 +76,4 @@ private slots:
     QAction *mActionRenameProperty;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/propertybrowser.cpp b/src/tiled/propertybrowser.cpp
index 9a3af39fda..5a3276e9b7 100644
--- a/src/tiled/propertybrowser.cpp
+++ b/src/tiled/propertybrowser.cpp
@@ -71,7 +71,6 @@
 #include <QMessageBox>
 
 namespace Tiled {
-namespace Internal {
 
 PropertyBrowser::PropertyBrowser(QWidget *parent)
     : QtTreePropertyBrowser(parent)
@@ -1891,10 +1890,10 @@ void PropertyBrowser::retranslateUi()
     mStaggerIndexNames.append(tr("Odd"));
     mStaggerIndexNames.append(tr("Even"));
 
-    mOrientationNames.append(QCoreApplication::translate("Tiled::Internal::NewMapDialog", "Orthogonal"));
-    mOrientationNames.append(QCoreApplication::translate("Tiled::Internal::NewMapDialog", "Isometric"));
-    mOrientationNames.append(QCoreApplication::translate("Tiled::Internal::NewMapDialog", "Isometric (Staggered)"));
-    mOrientationNames.append(QCoreApplication::translate("Tiled::Internal::NewMapDialog", "Hexagonal (Staggered)"));
+    mOrientationNames.append(QCoreApplication::translate("Tiled::NewMapDialog", "Orthogonal"));
+    mOrientationNames.append(QCoreApplication::translate("Tiled::NewMapDialog", "Isometric"));
+    mOrientationNames.append(QCoreApplication::translate("Tiled::NewMapDialog", "Isometric (Staggered)"));
+    mOrientationNames.append(QCoreApplication::translate("Tiled::NewMapDialog", "Hexagonal (Staggered)"));
 
     mTilesetOrientationNames.append(mOrientationNames.at(0));
     mTilesetOrientationNames.append(mOrientationNames.at(1));
@@ -1920,5 +1919,4 @@ void PropertyBrowser::retranslateUi()
     addProperties();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/propertybrowser.h b/src/tiled/propertybrowser.h
index fd32ae3b7c..e20b3467aa 100644
--- a/src/tiled/propertybrowser.h
+++ b/src/tiled/propertybrowser.h
@@ -43,8 +43,6 @@ class Tile;
 class TileLayer;
 class Tileset;
 
-namespace Internal {
-
 class Document;
 class MapDocument;
 class TilesetDocument;
@@ -247,5 +245,4 @@ inline Object *PropertyBrowser::object() const
     return mObject;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/raiselowerhelper.cpp b/src/tiled/raiselowerhelper.cpp
index 7f8d78bb93..0e0828acb6 100644
--- a/src/tiled/raiselowerhelper.cpp
+++ b/src/tiled/raiselowerhelper.cpp
@@ -33,7 +33,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 void RaiseLowerHelper::raise()
 {
@@ -267,5 +266,4 @@ void RaiseLowerHelper::push(const QList<QUndoCommand*> &commands,
     undoStack->endMacro();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/raiselowerhelper.h b/src/tiled/raiselowerhelper.h
index 05685ea767..5b09c1cff5 100644
--- a/src/tiled/raiselowerhelper.h
+++ b/src/tiled/raiselowerhelper.h
@@ -31,8 +31,6 @@ namespace Tiled {
 
 class ObjectGroup;
 
-namespace Internal {
-
 class MapDocument;
 class MapScene;
 
@@ -72,5 +70,4 @@ class RaiseLowerHelper
     RangeSet<int> mSelectionRanges;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/randompicker.h b/src/tiled/randompicker.h
index e5e25afca3..ebcf7f63a5 100644
--- a/src/tiled/randompicker.h
+++ b/src/tiled/randompicker.h
@@ -25,7 +25,6 @@
 #include <random>
 
 namespace Tiled {
-namespace Internal {
 
 inline std::default_random_engine &globalRandomEngine()
 {
@@ -97,5 +96,4 @@ class RandomPicker
     QMap<Real, T> mThresholds;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/rangeset.h b/src/tiled/rangeset.h
index 27d81a909b..dc5fba7116 100644
--- a/src/tiled/rangeset.h
+++ b/src/tiled/rangeset.h
@@ -23,7 +23,6 @@
 #include <map>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Logically, a set, but implemented as a set of ranges. This class is only
@@ -185,5 +184,4 @@ class RangeSet
     }
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/regionvaluetype.cpp b/src/tiled/regionvaluetype.cpp
index f9f9c946bd..11894f2abb 100644
--- a/src/tiled/regionvaluetype.cpp
+++ b/src/tiled/regionvaluetype.cpp
@@ -21,7 +21,6 @@
 #include "regionvaluetype.h"
 
 namespace Tiled {
-namespace Internal {
 
 RegionValueType::RegionValueType()
 {
@@ -57,5 +56,4 @@ QString RegionValueType::toString() const
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/regionvaluetype.h b/src/tiled/regionvaluetype.h
index c18a8b2378..d99b2f28fb 100644
--- a/src/tiled/regionvaluetype.h
+++ b/src/tiled/regionvaluetype.h
@@ -24,7 +24,6 @@
 #include <QRegion>
 
 namespace Tiled {
-namespace Internal {
 
 class RegionValueType
 {
@@ -42,13 +41,13 @@ class RegionValueType
 
     Q_INVOKABLE void add(const QRect &rect);
     Q_INVOKABLE void add(const QRectF &rect);
-    Q_INVOKABLE void add(const Tiled::Internal::RegionValueType &region);
+    Q_INVOKABLE void add(const Tiled::RegionValueType &region);
     Q_INVOKABLE void subtract(const QRect &rect);
     Q_INVOKABLE void subtract(const QRectF &rect);
-    Q_INVOKABLE void subtract(const Tiled::Internal::RegionValueType &region);
+    Q_INVOKABLE void subtract(const Tiled::RegionValueType &region);
     Q_INVOKABLE void intersect(const QRect &rect);
     Q_INVOKABLE void intersect(const QRectF &rect);
-    Q_INVOKABLE void intersect(const Tiled::Internal::RegionValueType &region);
+    Q_INVOKABLE void intersect(const Tiled::RegionValueType &region);
 
     QRect boundingRect() const;
     const QRegion &region() const;
@@ -113,7 +112,6 @@ inline const QRegion &RegionValueType::region() const
     return mRegion;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::RegionValueType)
+Q_DECLARE_METATYPE(Tiled::RegionValueType)
diff --git a/src/tiled/renamelayer.cpp b/src/tiled/renamelayer.cpp
index 3cba35adf2..261fd24cc6 100644
--- a/src/tiled/renamelayer.cpp
+++ b/src/tiled/renamelayer.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 RenameLayer::RenameLayer(MapDocument *mapDocument,
                          Layer *layer,
diff --git a/src/tiled/renamelayer.h b/src/tiled/renamelayer.h
index 586454e60a..ddc082090c 100644
--- a/src/tiled/renamelayer.h
+++ b/src/tiled/renamelayer.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 class RenameLayer : public QUndoCommand
@@ -48,5 +46,4 @@ class RenameLayer : public QUndoCommand
     QString mName;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/renameterrain.cpp b/src/tiled/renameterrain.cpp
index b377ea585b..3ade5e3ff5 100644
--- a/src/tiled/renameterrain.cpp
+++ b/src/tiled/renameterrain.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 RenameTerrain::RenameTerrain(TilesetDocument *tilesetDocument,
                              int terrainId,
@@ -52,5 +51,4 @@ void RenameTerrain::redo()
     mTerrainModel->setTerrainName(mTerrainId, mNewName);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/renameterrain.h b/src/tiled/renameterrain.h
index 48a3ab4094..ccd1d89599 100644
--- a/src/tiled/renameterrain.h
+++ b/src/tiled/renameterrain.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Tileset;
 
-namespace Internal {
-
 class TilesetDocument;
 class TilesetTerrainModel;
 
@@ -49,5 +47,4 @@ class RenameTerrain : public QUndoCommand
     QString mNewName;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/renamewangset.cpp b/src/tiled/renamewangset.cpp
index dc5760e1aa..216bf2587b 100644
--- a/src/tiled/renamewangset.cpp
+++ b/src/tiled/renamewangset.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Internal;
 
 RenameWangSet::RenameWangSet(TilesetDocument *tilesetDocument,
                              WangSet *wangSet,
diff --git a/src/tiled/renamewangset.h b/src/tiled/renamewangset.h
index 3bdacc936c..078b717961 100644
--- a/src/tiled/renamewangset.h
+++ b/src/tiled/renamewangset.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class WangSet;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class RenameWangSet : public QUndoCommand
@@ -47,5 +45,4 @@ class RenameWangSet : public QUndoCommand
     QString mNewName;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/reparentlayers.cpp b/src/tiled/reparentlayers.cpp
index a03a7ebeb7..fa7d7e72c9 100644
--- a/src/tiled/reparentlayers.cpp
+++ b/src/tiled/reparentlayers.cpp
@@ -28,7 +28,6 @@
 #include "qtcompat_p.h"
 
 namespace Tiled {
-namespace Internal {
 
 ReparentLayers::ReparentLayers(MapDocument *mapDocument,
                                const QList<Layer *> &layers,
@@ -97,5 +96,4 @@ void ReparentLayers::redo()
     mMapDocument->setCurrentLayer(currentLayer);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/reparentlayers.h b/src/tiled/reparentlayers.h
index 69f412fed9..d80243c284 100644
--- a/src/tiled/reparentlayers.h
+++ b/src/tiled/reparentlayers.h
@@ -28,8 +28,6 @@ namespace Tiled {
 class GroupLayer;
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -60,5 +58,4 @@ class ReparentLayers : public QUndoCommand
     QVector<UndoInfo> mUndoInfo;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/replacetemplate.cpp b/src/tiled/replacetemplate.cpp
index d3285dddbf..019938c042 100644
--- a/src/tiled/replacetemplate.cpp
+++ b/src/tiled/replacetemplate.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ReplaceTemplate::ReplaceTemplate(MapDocument *mapDocument,
                                  const ObjectTemplate *oldObjectTemplate,
@@ -51,5 +50,4 @@ void ReplaceTemplate::swap()
     std::swap(mOldObjectTemplate, mNewObjectTemplate);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/replacetemplate.h b/src/tiled/replacetemplate.h
index e9023ffad9..a7679506c8 100644
--- a/src/tiled/replacetemplate.h
+++ b/src/tiled/replacetemplate.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class ObjectTemplate;
 
-namespace Internal {
-
 class MapDocument;
 
 class ReplaceTemplate : public QUndoCommand
@@ -51,5 +49,4 @@ class ReplaceTemplate : public QUndoCommand
     const ObjectTemplate *mNewObjectTemplate;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/replacetileset.cpp b/src/tiled/replacetileset.cpp
index 8a4b0c1534..241d8b9c79 100644
--- a/src/tiled/replacetileset.cpp
+++ b/src/tiled/replacetileset.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ReplaceTileset::ReplaceTileset(MapDocument *mapDocument,
                                int index,
@@ -45,5 +44,4 @@ void ReplaceTileset::swap()
     mTileset = mMapDocument->replaceTileset(mIndex, mTileset);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/replacetileset.h b/src/tiled/replacetileset.h
index a6210df90a..78fa0a624f 100644
--- a/src/tiled/replacetileset.h
+++ b/src/tiled/replacetileset.h
@@ -25,7 +25,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -47,5 +46,4 @@ class ReplaceTileset : public QUndoCommand
     SharedTileset mTileset;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/resizedialog.cpp b/src/tiled/resizedialog.cpp
index 99a519f195..50bb3f735e 100644
--- a/src/tiled/resizedialog.cpp
+++ b/src/tiled/resizedialog.cpp
@@ -27,7 +27,7 @@
 
 #include <QSettings>
 
-using namespace Tiled::Internal;
+using namespace Tiled;
 
 static const char * const REMOVE_OBJECTS_KEY = "ResizeMap/RemoveObjects";
 
diff --git a/src/tiled/resizedialog.h b/src/tiled/resizedialog.h
index 9b68890f88..fd1a890d17 100644
--- a/src/tiled/resizedialog.h
+++ b/src/tiled/resizedialog.h
@@ -29,7 +29,6 @@ class ResizeDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 class ResizeDialog : public QDialog
 {
@@ -57,5 +56,4 @@ private slots:
     Ui::ResizeDialog *mUi;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/resizedialog.ui b/src/tiled/resizedialog.ui
index 5b1a686c58..6afb278db1 100644
--- a/src/tiled/resizedialog.ui
+++ b/src/tiled/resizedialog.ui
@@ -140,7 +140,7 @@
      </property>
      <layout class="QVBoxLayout" name="_5">
       <item>
-       <widget class="Tiled::Internal::ResizeHelper" name="resizeHelper" native="true"/>
+       <widget class="Tiled::ResizeHelper" name="resizeHelper" native="true"/>
       </item>
      </layout>
     </widget>
@@ -169,7 +169,7 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>Tiled::Internal::ResizeHelper</class>
+   <class>Tiled::ResizeHelper</class>
    <extends>QWidget</extends>
    <header>resizehelper.h</header>
    <container>1</container>
diff --git a/src/tiled/resizehelper.cpp b/src/tiled/resizehelper.cpp
index ffda00e562..ddd61488c9 100644
--- a/src/tiled/resizehelper.cpp
+++ b/src/tiled/resizehelper.cpp
@@ -24,7 +24,7 @@
 #include <QPainter>
 #include <QResizeEvent>
 
-using namespace Tiled::Internal;
+using namespace Tiled;
 
 ResizeHelper::ResizeHelper(QWidget *parent)
     : QWidget(parent)
diff --git a/src/tiled/resizehelper.h b/src/tiled/resizehelper.h
index 980ee7bbd7..0cab3d75aa 100644
--- a/src/tiled/resizehelper.h
+++ b/src/tiled/resizehelper.h
@@ -30,7 +30,6 @@ class QMouseEvent;
 class QResizeEvent;
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A special widget designed as an aid for resizing a canvas. Based on a
@@ -98,5 +97,4 @@ public slots:
     std::function<QImage(QSize)> mMiniMapRenderer;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/resizemap.cpp b/src/tiled/resizemap.cpp
index abaf01fc20..ec40b6b54b 100644
--- a/src/tiled/resizemap.cpp
+++ b/src/tiled/resizemap.cpp
@@ -26,7 +26,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 ResizeMap::ResizeMap(MapDocument *mapDocument,
                      const QSize &size,
@@ -60,5 +59,4 @@ void ResizeMap::swapSize()
     emit mMapDocument->mapChanged();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/resizemap.h b/src/tiled/resizemap.h
index 64419ca0dd..6e66b84249 100644
--- a/src/tiled/resizemap.h
+++ b/src/tiled/resizemap.h
@@ -24,7 +24,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -49,5 +48,4 @@ class ResizeMap : public QUndoCommand
     QSize mSize;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/resizemapobject.cpp b/src/tiled/resizemapobject.cpp
index c34642214a..174bd2f020 100644
--- a/src/tiled/resizemapobject.cpp
+++ b/src/tiled/resizemapobject.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ResizeMapObject::ResizeMapObject(MapDocument *mapDocument,
                                  MapObject *mapObject,
diff --git a/src/tiled/resizemapobject.h b/src/tiled/resizemapobject.h
index 466b1dbda6..e3ee2d7e09 100644
--- a/src/tiled/resizemapobject.h
+++ b/src/tiled/resizemapobject.h
@@ -27,8 +27,6 @@ namespace Tiled {
 
 class MapObject;
 
-namespace Internal {
-
 class MapDocument;
 
 class ResizeMapObject : public QUndoCommand
@@ -54,5 +52,4 @@ class ResizeMapObject : public QUndoCommand
     bool mOldChangeState;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/resizetilelayer.cpp b/src/tiled/resizetilelayer.cpp
index 4dbf62f22a..f4c1272d3d 100644
--- a/src/tiled/resizetilelayer.cpp
+++ b/src/tiled/resizetilelayer.cpp
@@ -28,7 +28,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ResizeTileLayer::ResizeTileLayer(MapDocument *mapDocument,
                                  TileLayer *layer,
diff --git a/src/tiled/resizetilelayer.h b/src/tiled/resizetilelayer.h
index c2b7b08cac..a6cefc9182 100644
--- a/src/tiled/resizetilelayer.h
+++ b/src/tiled/resizetilelayer.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class Layer;
 class TileLayer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -61,5 +59,4 @@ class ResizeTileLayer : public QUndoCommand
     TileLayer *mResizedLayer;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/reversingproxymodel.cpp b/src/tiled/reversingproxymodel.cpp
index 470230f209..1f48e67a53 100644
--- a/src/tiled/reversingproxymodel.cpp
+++ b/src/tiled/reversingproxymodel.cpp
@@ -25,7 +25,6 @@
 #include "reversingproxymodel.h"
 
 namespace Tiled {
-namespace Internal {
 
 // Stupid hack needed because createIndex is protected
 class FriendModel : public QAbstractItemModel
@@ -450,4 +449,3 @@ void ReversingProxyModel::sourceRowsRemoved(const QModelIndex &parent, int start
 }
 
 } // namespace Tiled
-} // namespace Internal
diff --git a/src/tiled/reversingproxymodel.h b/src/tiled/reversingproxymodel.h
index 07f8614515..ef7dd33569 100644
--- a/src/tiled/reversingproxymodel.h
+++ b/src/tiled/reversingproxymodel.h
@@ -23,7 +23,6 @@
 #include <QAbstractProxyModel>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Displays the source model "upside down".
@@ -83,4 +82,3 @@ private slots:
 };
 
 } // namespace Tiled
-} // namespace Internal
diff --git a/src/tiled/rotatemapobject.cpp b/src/tiled/rotatemapobject.cpp
index e2951ad465..abd260185c 100644
--- a/src/tiled/rotatemapobject.cpp
+++ b/src/tiled/rotatemapobject.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 RotateMapObject::RotateMapObject(MapDocument *mapDocument,
                                  MapObject *mapObject,
diff --git a/src/tiled/rotatemapobject.h b/src/tiled/rotatemapobject.h
index c7297d62a1..284888a269 100644
--- a/src/tiled/rotatemapobject.h
+++ b/src/tiled/rotatemapobject.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class MapObject;
 
-namespace Internal {
-
 class MapDocument;
 
 class RotateMapObject : public QUndoCommand
@@ -53,5 +51,4 @@ class RotateMapObject : public QUndoCommand
     bool mOldChangeState;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/scriptmanager.cpp b/src/tiled/scriptmanager.cpp
index 89a86d9811..f0be2ac136 100644
--- a/src/tiled/scriptmanager.cpp
+++ b/src/tiled/scriptmanager.cpp
@@ -35,7 +35,6 @@
 #include <QtDebug>
 
 namespace Tiled {
-namespace Internal {
 
 std::unique_ptr<ScriptManager> ScriptManager::mInstance;
 
@@ -126,5 +125,4 @@ void ScriptManager::throwError(const QString &message)
 #endif
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/scriptmanager.h b/src/tiled/scriptmanager.h
index 5c14daa755..e6d2a50901 100644
--- a/src/tiled/scriptmanager.h
+++ b/src/tiled/scriptmanager.h
@@ -28,7 +28,6 @@
 class QJSEngine;
 
 namespace Tiled {
-namespace Internal {
 
 class ScriptModule;
 
@@ -72,5 +71,4 @@ inline QJSEngine *ScriptManager::engine() const
     return mEngine;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/scriptmodule.cpp b/src/tiled/scriptmodule.cpp
index 1f535a06ce..7cceb2fbe2 100644
--- a/src/tiled/scriptmodule.cpp
+++ b/src/tiled/scriptmodule.cpp
@@ -30,7 +30,6 @@
 #include <QMessageBox>
 
 namespace Tiled {
-namespace Internal {
 
 ScriptModule::ScriptModule(QObject *parent)
     : QObject(parent)
@@ -170,5 +169,4 @@ void ScriptModule::currentDocumentChanged(Document *document)
     emit activeAssetChanged(document ? document->editable() : nullptr);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/scriptmodule.h b/src/tiled/scriptmodule.h
index 97181aa594..bb2d6d42a1 100644
--- a/src/tiled/scriptmodule.h
+++ b/src/tiled/scriptmodule.h
@@ -28,8 +28,6 @@ namespace Tiled {
 
 class LoggingInterface;
 
-namespace Internal {
-
 class EditableAsset;
 
 /**
@@ -43,7 +41,7 @@ class ScriptModule : public QObject
     Q_PROPERTY(QString platform READ platform)
     Q_PROPERTY(QString arch READ arch)
 
-    Q_PROPERTY(Tiled::Internal::EditableAsset *activeAsset READ activeAsset WRITE setActiveAsset NOTIFY activeAssetChanged)
+    Q_PROPERTY(Tiled::EditableAsset *activeAsset READ activeAsset WRITE setActiveAsset NOTIFY activeAssetChanged)
     Q_PROPERTY(QList<QObject*> openAssets READ openAssets)
 
 public:
@@ -60,13 +58,13 @@ class ScriptModule : public QObject
     QList<QObject*> openAssets() const;
 
 signals:
-    void assetCreated(Tiled::Internal::EditableAsset *asset);
-    void assetOpened(Tiled::Internal::EditableAsset *asset);
-    void assetAboutToBeSaved(Tiled::Internal::EditableAsset *asset);
-    void assetSaved(Tiled::Internal::EditableAsset *asset);
-    void assetAboutToBeClosed(Tiled::Internal::EditableAsset *asset);
+    void assetCreated(Tiled::EditableAsset *asset);
+    void assetOpened(Tiled::EditableAsset *asset);
+    void assetAboutToBeSaved(Tiled::EditableAsset *asset);
+    void assetSaved(Tiled::EditableAsset *asset);
+    void assetAboutToBeClosed(Tiled::EditableAsset *asset);
 
-    void activeAssetChanged(Tiled::Internal::EditableAsset *asset);
+    void activeAssetChanged(Tiled::EditableAsset *asset);
 
 public slots:
     void trigger(const QByteArray &actionName) const;
@@ -90,5 +88,4 @@ private slots:
     LoggingInterface *mLogger;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/selectionrectangle.cpp b/src/tiled/selectionrectangle.cpp
index 35a0a59641..a205b0a7b5 100644
--- a/src/tiled/selectionrectangle.cpp
+++ b/src/tiled/selectionrectangle.cpp
@@ -28,7 +28,6 @@
 #include <QPalette>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 SelectionRectangle::SelectionRectangle(QGraphicsItem *parent)
     : QGraphicsItem(parent)
diff --git a/src/tiled/selectionrectangle.h b/src/tiled/selectionrectangle.h
index 60e19105eb..7d0bfc0288 100644
--- a/src/tiled/selectionrectangle.h
+++ b/src/tiled/selectionrectangle.h
@@ -23,7 +23,6 @@
 #include <QGraphicsItem>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * The rectangle used for indicating the dragged area when selecting items.
@@ -44,5 +43,4 @@ class SelectionRectangle : public QGraphicsItem
     QRectF mRectangle;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/selectsametiletool.cpp b/src/tiled/selectsametiletool.cpp
index 30c104adb3..dce3ab2789 100644
--- a/src/tiled/selectsametiletool.cpp
+++ b/src/tiled/selectsametiletool.cpp
@@ -25,7 +25,6 @@
 #include "mapdocument.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 SelectSameTileTool::SelectSameTileTool(QObject *parent)
     : AbstractTileSelectionTool(tr("Select Same Tile"),
diff --git a/src/tiled/selectsametiletool.h b/src/tiled/selectsametiletool.h
index 08ed62fb2f..badb556d28 100644
--- a/src/tiled/selectsametiletool.h
+++ b/src/tiled/selectsametiletool.h
@@ -27,7 +27,6 @@
 #include "tilelayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -47,5 +46,4 @@ class SelectSameTileTool : public AbstractTileSelectionTool
     void tilePositionChanged(const QPoint &tilePos) override;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/shapefilltool.cpp b/src/tiled/shapefilltool.cpp
index cb606aae5b..f7da5b1e22 100644
--- a/src/tiled/shapefilltool.cpp
+++ b/src/tiled/shapefilltool.cpp
@@ -34,7 +34,6 @@
 #include <memory>
 
 using namespace Tiled;
-using namespace Internal;
 
 ShapeFillTool::ShapeFillTool(QObject *parent)
     : AbstractTileFillTool(tr("Shape Fill Tool"),
diff --git a/src/tiled/shapefilltool.h b/src/tiled/shapefilltool.h
index c9944d2e79..82be7ef74b 100644
--- a/src/tiled/shapefilltool.h
+++ b/src/tiled/shapefilltool.h
@@ -25,7 +25,6 @@
 class QAction;
 
 namespace Tiled {
-namespace Internal {
 
 class ShapeFillTool : public AbstractTileFillTool
 {
@@ -69,5 +68,4 @@ class ShapeFillTool : public AbstractTileFillTool
     void updateFillOverlay();
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/snaphelper.cpp b/src/tiled/snaphelper.cpp
index 91a76a21cd..a061ee1855 100644
--- a/src/tiled/snaphelper.cpp
+++ b/src/tiled/snaphelper.cpp
@@ -24,7 +24,6 @@
 #include "preferences.h"
 
 namespace Tiled {
-namespace Internal {
 
 SnapHelper::SnapHelper(const MapRenderer *renderer,
                        Qt::KeyboardModifiers modifiers)
@@ -63,5 +62,4 @@ void SnapHelper::snap(QPointF &pixelPos) const
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/snaphelper.h b/src/tiled/snaphelper.h
index e904d69d18..8a23d67031 100644
--- a/src/tiled/snaphelper.h
+++ b/src/tiled/snaphelper.h
@@ -24,7 +24,6 @@
 #include "maprenderer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class SnapHelper
 {
@@ -44,5 +43,4 @@ class SnapHelper
     bool mSnapToPixels;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/stampactions.cpp b/src/tiled/stampactions.cpp
index c250659a58..7262d6fa9b 100644
--- a/src/tiled/stampactions.cpp
+++ b/src/tiled/stampactions.cpp
@@ -24,7 +24,6 @@
 #include <QToolBar>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 StampActions::StampActions(QObject *parent) : QObject(parent)
 {
diff --git a/src/tiled/stampactions.h b/src/tiled/stampactions.h
index 6d11d0fc83..06e1d7a9be 100644
--- a/src/tiled/stampactions.h
+++ b/src/tiled/stampactions.h
@@ -26,7 +26,6 @@ class QAction;
 class QToolBar;
 
 namespace Tiled {
-namespace Internal {
 
 class StampActions : public QObject
 {
@@ -55,5 +54,4 @@ class StampActions : public QObject
     QAction *mRotateRight;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/stampbrush.cpp b/src/tiled/stampbrush.cpp
index 5c95d75fad..ae3e1503d3 100644
--- a/src/tiled/stampbrush.cpp
+++ b/src/tiled/stampbrush.cpp
@@ -43,7 +43,6 @@
 #include <memory>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 StampBrush::StampBrush(QObject *parent)
     : AbstractTileTool(tr("Stamp Brush"),
diff --git a/src/tiled/stampbrush.h b/src/tiled/stampbrush.h
index 1cbfb4e433..cf0e5344f5 100644
--- a/src/tiled/stampbrush.h
+++ b/src/tiled/stampbrush.h
@@ -32,8 +32,6 @@ namespace Tiled {
 class Tile;
 class WangSet;
 
-namespace Internal {
-
 class MapDocument;
 class StampActions;
 class WangFiller;
@@ -162,5 +160,4 @@ public slots:
     StampActions *mStampActions;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/standardautoupdater.cpp b/src/tiled/standardautoupdater.cpp
index 629674ca78..185bd56b5d 100644
--- a/src/tiled/standardautoupdater.cpp
+++ b/src/tiled/standardautoupdater.cpp
@@ -22,8 +22,7 @@
 
 #include "preferences.h"
 
-using namespace Tiled::Internal;
-
+using namespace Tiled;
 
 StandardAutoUpdater::StandardAutoUpdater()
 {
diff --git a/src/tiled/stylehelper.cpp b/src/tiled/stylehelper.cpp
index 51b6abe9a7..49a2070e4d 100644
--- a/src/tiled/stylehelper.cpp
+++ b/src/tiled/stylehelper.cpp
@@ -29,7 +29,6 @@
 #include <QStyleFactory>
 
 namespace Tiled {
-namespace Internal {
 
 StyleHelper *StyleHelper::mInstance;
 
@@ -143,5 +142,4 @@ void StyleHelper::apply()
     emit styleApplied();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/stylehelper.h b/src/tiled/stylehelper.h
index cb71ac4137..dbf82748cc 100644
--- a/src/tiled/stylehelper.h
+++ b/src/tiled/stylehelper.h
@@ -24,7 +24,6 @@
 #include <QString>
 
 namespace Tiled {
-namespace Internal {
 
 class StyleHelper : public QObject
 {
@@ -51,5 +50,4 @@ class StyleHelper : public QObject
     static StyleHelper *mInstance;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/swaptiles.cpp b/src/tiled/swaptiles.cpp
index d52068cdd6..de2fa9c7fd 100644
--- a/src/tiled/swaptiles.cpp
+++ b/src/tiled/swaptiles.cpp
@@ -29,7 +29,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 SwapTiles::SwapTiles(MapDocument *mapDocument,
                      Tile *tile1,
@@ -96,5 +95,4 @@ void SwapTiles::swap()
         emit mMapDocument->mapObjectModel()->objectsChanged(changedObjects);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/swaptiles.h b/src/tiled/swaptiles.h
index ba58b78d9c..4053b97c46 100644
--- a/src/tiled/swaptiles.h
+++ b/src/tiled/swaptiles.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class Tile;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -61,7 +59,6 @@ class SwapTiles : public QUndoCommand
     Tile *mTile2;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
 #endif // SWAPTILES_H
diff --git a/src/tiled/templatesdock.cpp b/src/tiled/templatesdock.cpp
index c9de23c87e..299e77f396 100644
--- a/src/tiled/templatesdock.cpp
+++ b/src/tiled/templatesdock.cpp
@@ -51,7 +51,6 @@
 #include <QUndoStack>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 // This references created dummy documents, to make sure they are shared if the
 // same template is open in the MapEditor and the TilesetEditor.
diff --git a/src/tiled/templatesdock.h b/src/tiled/templatesdock.h
index f2e8a7bffd..617b770d70 100644
--- a/src/tiled/templatesdock.h
+++ b/src/tiled/templatesdock.h
@@ -38,8 +38,6 @@ class ObjectTemplate;
 class MapObject;
 class Tile;
 
-namespace Internal {
-
 class AbstractTool;
 class MapScene;
 class MapView;
@@ -135,5 +133,4 @@ public slots:
 inline void TemplatesDock::setPropertiesDock(PropertiesDock *propertiesDock)
 { mPropertiesDock = propertiesDock; }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/terrainbrush.cpp b/src/tiled/terrainbrush.cpp
index 0af32f025c..3a7cacb3dd 100644
--- a/src/tiled/terrainbrush.cpp
+++ b/src/tiled/terrainbrush.cpp
@@ -42,7 +42,6 @@
 #include <climits>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TerrainBrush::TerrainBrush(QObject *parent)
     : AbstractTileTool(tr("Terrain Brush"),
diff --git a/src/tiled/terrainbrush.h b/src/tiled/terrainbrush.h
index 2b806a08cb..e108b5d967 100644
--- a/src/tiled/terrainbrush.h
+++ b/src/tiled/terrainbrush.h
@@ -30,8 +30,6 @@ namespace Tiled {
 class Tile;
 class Terrain;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -142,5 +140,4 @@ class TerrainBrush : public AbstractTileTool
     int mLineReferenceX, mLineReferenceY;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/terraindock.cpp b/src/tiled/terraindock.cpp
index b3dd01ba04..9aef69fc8a 100644
--- a/src/tiled/terraindock.cpp
+++ b/src/tiled/terraindock.cpp
@@ -44,10 +44,8 @@
 #include <QTreeView>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace Tiled {
-namespace Internal {
 
 static Terrain *firstTerrain(MapDocument *mapDocument)
 {
@@ -99,7 +97,6 @@ class TerrainFilterModel : public QSortFilterProxyModel
     bool mEnabled;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
 TerrainDock::TerrainDock(QWidget *parent)
diff --git a/src/tiled/terraindock.h b/src/tiled/terraindock.h
index c9cbecb6cf..a9d7207c53 100644
--- a/src/tiled/terraindock.h
+++ b/src/tiled/terraindock.h
@@ -34,8 +34,6 @@ namespace Tiled {
 
 class Terrain;
 
-namespace Internal {
-
 class Document;
 class TerrainFilterModel;
 class TerrainModel;
@@ -119,5 +117,4 @@ private slots:
     bool mInitializing;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/terrainmodel.cpp b/src/tiled/terrainmodel.cpp
index c623d7e6e8..4be94d1662 100644
--- a/src/tiled/terrainmodel.cpp
+++ b/src/tiled/terrainmodel.cpp
@@ -38,7 +38,6 @@
 #include <QPalette>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TerrainModel::TerrainModel(QAbstractItemModel *tilesetDocumentsModel,
                            QObject *parent):
diff --git a/src/tiled/terrainmodel.h b/src/tiled/terrainmodel.h
index 402d7cc6bd..8a70c2d68b 100644
--- a/src/tiled/terrainmodel.h
+++ b/src/tiled/terrainmodel.h
@@ -30,8 +30,6 @@ namespace Tiled {
 class Tileset;
 class Terrain;
 
-namespace Internal {
-
 class TilesetDocument;
 
 /**
@@ -107,5 +105,4 @@ private slots:
     QList<TilesetDocument*> mTilesetDocuments;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/terrainview.cpp b/src/tiled/terrainview.cpp
index 0c1d9c0790..f09eab5229 100644
--- a/src/tiled/terrainview.cpp
+++ b/src/tiled/terrainview.cpp
@@ -37,7 +37,6 @@
 #include <QWheelEvent>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TerrainView::TerrainView(QWidget *parent)
     : QTreeView(parent)
diff --git a/src/tiled/terrainview.h b/src/tiled/terrainview.h
index c12d8378ef..4f84f52cb1 100644
--- a/src/tiled/terrainview.h
+++ b/src/tiled/terrainview.h
@@ -26,7 +26,6 @@
 #include <QTreeView>
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetDocument;
 class Zoomable;
@@ -70,7 +69,6 @@ private slots:
     TilesetDocument *mTilesetDocument;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::TerrainView *)
+Q_DECLARE_METATYPE(Tiled::TerrainView *)
diff --git a/src/tiled/texteditordialog.cpp b/src/tiled/texteditordialog.cpp
index f1f3155bbe..eef207363f 100644
--- a/src/tiled/texteditordialog.cpp
+++ b/src/tiled/texteditordialog.cpp
@@ -24,7 +24,6 @@
 #include "utils.h"
 
 namespace Tiled {
-namespace Internal {
 
 TextEditorDialog::TextEditorDialog(QWidget *parent)
     : QDialog(parent)
@@ -67,5 +66,4 @@ void TextEditorDialog::changeEvent(QEvent *e)
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/texteditordialog.h b/src/tiled/texteditordialog.h
index ab50ad61a1..9eebe71c71 100644
--- a/src/tiled/texteditordialog.h
+++ b/src/tiled/texteditordialog.h
@@ -27,7 +27,6 @@ class TextEditorDialog;
 }
 
 namespace Tiled {
-namespace Internal {
 
 class TextEditorDialog : public QDialog
 {
@@ -47,5 +46,4 @@ class TextEditorDialog : public QDialog
     Ui::TextEditorDialog *mUi;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/textpropertyedit.cpp b/src/tiled/textpropertyedit.cpp
index bd1629aede..4ff9e9c182 100644
--- a/src/tiled/textpropertyedit.cpp
+++ b/src/tiled/textpropertyedit.cpp
@@ -34,7 +34,6 @@
 #include <QDebug>
 
 namespace Tiled {
-namespace Internal {
 
 namespace {
 
@@ -181,5 +180,4 @@ void TextPropertyEdit::onButtonClicked()
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/textpropertyedit.h b/src/tiled/textpropertyedit.h
index 628f0390f4..691b3499ec 100644
--- a/src/tiled/textpropertyedit.h
+++ b/src/tiled/textpropertyedit.h
@@ -28,7 +28,6 @@
 class QLineEdit;
 
 namespace Tiled {
-namespace Internal {
 
 QString escapeNewlines(const QString &string);
 
@@ -60,5 +59,4 @@ private slots:
     QString mCachedText;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tileanimationeditor.cpp b/src/tiled/tileanimationeditor.cpp
index 4ee5b7a6a7..45ec5d6ad7 100644
--- a/src/tiled/tileanimationeditor.cpp
+++ b/src/tiled/tileanimationeditor.cpp
@@ -43,7 +43,6 @@
 static const char * const FRAME_DURATION_KEY = "Animation/FrameDuration";
 
 namespace Tiled {
-namespace Internal {
 
 class FrameListModel : public QAbstractListModel
 {
@@ -565,7 +564,6 @@ void TileAnimationEditor::resetPreview()
                                                   "Preview"));
 }
 
-} // namespace Internal
 } // namespace Tiled
 
 #include "tileanimationeditor.moc"
diff --git a/src/tiled/tileanimationeditor.h b/src/tiled/tileanimationeditor.h
index 36073b52c8..f14562e4f3 100644
--- a/src/tiled/tileanimationeditor.h
+++ b/src/tiled/tileanimationeditor.h
@@ -34,8 +34,6 @@ class Tile;
 class TileAnimationDriver;
 class Tileset;
 
-namespace Internal {
-
 class FrameListModel;
 class TilesetDocument;
 
@@ -92,5 +90,4 @@ private slots:
     int mPreviewUnusedTime;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tileanimationeditor.ui b/src/tiled/tileanimationeditor.ui
index 4fc9227605..0dd13fcde7 100644
--- a/src/tiled/tileanimationeditor.ui
+++ b/src/tiled/tileanimationeditor.ui
@@ -153,7 +153,7 @@
        </property>
       </widget>
      </widget>
-     <widget class="Tiled::Internal::TilesetView" name="tilesetView">
+     <widget class="Tiled::TilesetView" name="tilesetView">
       <property name="sizePolicy">
        <sizepolicy hsizetype="Expanding" vsizetype="Preferred">
         <horstretch>0</horstretch>
@@ -186,7 +186,7 @@
  </widget>
  <customwidgets>
   <customwidget>
-   <class>Tiled::Internal::TilesetView</class>
+   <class>Tiled::TilesetView</class>
    <extends>QTableView</extends>
    <header location="global">tilesetview.h</header>
   </customwidget>
diff --git a/src/tiled/tilecollisiondock.cpp b/src/tiled/tilecollisiondock.cpp
index ecdd4c6337..e4eead8e2d 100644
--- a/src/tiled/tilecollisiondock.cpp
+++ b/src/tiled/tilecollisiondock.cpp
@@ -55,7 +55,6 @@
 #include <QVBoxLayout>
 
 namespace Tiled {
-namespace Internal {
 
 TileCollisionDock::TileCollisionDock(QWidget *parent)
     : QDockWidget(parent)
@@ -375,8 +374,7 @@ void TileCollisionDock::changeEvent(QEvent *e)
 
 void TileCollisionDock::retranslateUi()
 {
-    setWindowTitle(QCoreApplication::translate("Tiled::Internal::MainWindow", "Tile Collision Editor"));
+    setWindowTitle(QCoreApplication::translate("Tiled::MainWindow", "Tile Collision Editor"));
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilecollisiondock.h b/src/tiled/tilecollisiondock.h
index 703b86588b..32bc4d26a5 100644
--- a/src/tiled/tilecollisiondock.h
+++ b/src/tiled/tilecollisiondock.h
@@ -32,8 +32,6 @@ class Object;
 class Tile;
 class Tileset;
 
-namespace Internal {
-
 class AbstractTool;
 class MapScene;
 class MapView;
@@ -117,7 +115,6 @@ inline bool TileCollisionDock::hasSelectedObjects() const
     return mHasSelectedObjects;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
 #endif // TILECOLLISIONDOCK_H
diff --git a/src/tiled/tiledapplication.cpp b/src/tiled/tiledapplication.cpp
index 877dc86032..ede806dd7d 100644
--- a/src/tiled/tiledapplication.cpp
+++ b/src/tiled/tiledapplication.cpp
@@ -25,7 +25,6 @@
 #include <QJsonDocument>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TiledApplication::TiledApplication(int &argc, char **argv) :
     QtSingleApplication(argc, argv)
diff --git a/src/tiled/tiledapplication.h b/src/tiled/tiledapplication.h
index 9353c4c585..411de4810a 100644
--- a/src/tiled/tiledapplication.h
+++ b/src/tiled/tiledapplication.h
@@ -23,7 +23,6 @@
 #include <QtSingleApplication>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Custom QApplication subclass which handles the QFileOpenEvent, in order
@@ -46,5 +45,4 @@ private slots:
     void onMessageReceived(const QString &message);
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tiledproxystyle.cpp b/src/tiled/tiledproxystyle.cpp
index 2e8b6d2d7f..84db7b00f5 100644
--- a/src/tiled/tiledproxystyle.cpp
+++ b/src/tiled/tiledproxystyle.cpp
@@ -33,7 +33,6 @@
 #include <QtMath>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 /*
  * Below there are a lot of helper functions which are copied from various
diff --git a/src/tiled/tiledproxystyle.h b/src/tiled/tiledproxystyle.h
index 7ea832b795..db72eb0349 100644
--- a/src/tiled/tiledproxystyle.h
+++ b/src/tiled/tiledproxystyle.h
@@ -23,7 +23,6 @@
 #include <QProxyStyle>
 
 namespace Tiled {
-namespace Internal {
 
 class TiledProxyStyle : public QProxyStyle
 {
@@ -86,5 +85,4 @@ inline bool TiledProxyStyle::isDark() const
     return mIsDark;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilelayeritem.cpp b/src/tiled/tilelayeritem.cpp
index 5eb69871fe..d29e69e5d0 100644
--- a/src/tiled/tilelayeritem.cpp
+++ b/src/tiled/tilelayeritem.cpp
@@ -29,7 +29,6 @@
 #include <QStyleOptionGraphicsItem>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TileLayerItem::TileLayerItem(TileLayer *layer, MapDocument *mapDocument, QGraphicsItem *parent)
     : LayerItem(layer, parent)
diff --git a/src/tiled/tilelayeritem.h b/src/tiled/tilelayeritem.h
index ebd6a340eb..343f18306b 100644
--- a/src/tiled/tilelayeritem.h
+++ b/src/tiled/tilelayeritem.h
@@ -25,7 +25,6 @@
 #include "tilelayer.h"
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -71,5 +70,4 @@ inline TileLayer *TileLayerItem::tileLayer() const
     return static_cast<TileLayer*>(layer());
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilepainter.cpp b/src/tiled/tilepainter.cpp
index 4c79774bcf..7eba968e5c 100644
--- a/src/tiled/tilepainter.cpp
+++ b/src/tiled/tilepainter.cpp
@@ -27,7 +27,6 @@
 #include <QQueue>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace {
 
diff --git a/src/tiled/tilepainter.h b/src/tiled/tilepainter.h
index d3c7ef1fab..bdddd749c3 100644
--- a/src/tiled/tilepainter.h
+++ b/src/tiled/tilepainter.h
@@ -26,7 +26,6 @@
 #include <QRegion>
 
 namespace Tiled {
-namespace Internal {
 
 class MapDocument;
 
@@ -124,4 +123,3 @@ inline Cell TilePainter::cellAt(QPoint pos) const
 }
 
 } // namespace Tiled
-} // namespace Internal
diff --git a/src/tiled/tileselectionitem.cpp b/src/tiled/tileselectionitem.cpp
index 6dc114063c..66c4a2ee1a 100644
--- a/src/tiled/tileselectionitem.cpp
+++ b/src/tiled/tileselectionitem.cpp
@@ -31,7 +31,6 @@
 #include <QStyleOptionGraphicsItem>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TileSelectionItem::TileSelectionItem(MapDocument *mapDocument,
                                      QGraphicsItem *parent)
diff --git a/src/tiled/tileselectionitem.h b/src/tiled/tileselectionitem.h
index 350ec8825f..27d0380b85 100644
--- a/src/tiled/tileselectionitem.h
+++ b/src/tiled/tileselectionitem.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class Layer;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -63,5 +61,4 @@ private slots:
     QRectF mBoundingRect;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tileselectiontool.cpp b/src/tiled/tileselectiontool.cpp
index 58c0603d03..290f6d0ea1 100644
--- a/src/tiled/tileselectiontool.cpp
+++ b/src/tiled/tileselectiontool.cpp
@@ -30,7 +30,6 @@
 #include <QApplication>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TileSelectionTool::TileSelectionTool(QObject *parent)
     : AbstractTileSelectionTool(tr("Rectangular Select"),
diff --git a/src/tiled/tileselectiontool.h b/src/tiled/tileselectiontool.h
index 45759fff95..242858cc7c 100644
--- a/src/tiled/tileselectiontool.h
+++ b/src/tiled/tileselectiontool.h
@@ -23,7 +23,6 @@
 #include "abstracttileselectiontool.h"
 
 namespace Tiled {
-namespace Internal {
 
 class TileSelectionTool : public AbstractTileSelectionTool
 {
@@ -54,5 +53,4 @@ class TileSelectionTool : public AbstractTileSelectionTool
     bool mSelecting;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetchanges.cpp b/src/tiled/tilesetchanges.cpp
index 3c3148fade..f8a77c49d1 100644
--- a/src/tiled/tilesetchanges.cpp
+++ b/src/tiled/tilesetchanges.cpp
@@ -27,7 +27,6 @@
 #include <QCoreApplication>
 
 namespace Tiled {
-namespace Internal {
 
 RenameTileset::RenameTileset(TilesetDocument *tilesetDocument,
                              const QString &newName)
@@ -211,5 +210,4 @@ void ChangeTilesetGridSize::swap()
     emit mTilesetDocument->tilesetChanged(&tileset);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetchanges.h b/src/tiled/tilesetchanges.h
index f40d0ad310..94e8604e5e 100644
--- a/src/tiled/tilesetchanges.h
+++ b/src/tiled/tilesetchanges.h
@@ -33,8 +33,6 @@ namespace Tiled {
 
 class Tileset;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class RenameTileset : public QUndoCommand
@@ -175,5 +173,4 @@ class ChangeTilesetGridSize : public QUndoCommand
     QSize mGridSize;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetdock.cpp b/src/tiled/tilesetdock.cpp
index 28ac96fc45..c8102b3850 100644
--- a/src/tiled/tilesetdock.cpp
+++ b/src/tiled/tilesetdock.cpp
@@ -69,7 +69,6 @@
 #include <functional>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace {
 
diff --git a/src/tiled/tilesetdock.h b/src/tiled/tilesetdock.h
index 473a7c78bb..01355fd7b6 100644
--- a/src/tiled/tilesetdock.h
+++ b/src/tiled/tilesetdock.h
@@ -46,8 +46,6 @@ class Tile;
 class TileLayer;
 class Tileset;
 
-namespace Internal {
-
 class Document;
 class MapDocument;
 class TilesetDocument;
@@ -188,5 +186,4 @@ private slots:
     bool mSynchronizingSelection;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetdocument.cpp b/src/tiled/tilesetdocument.cpp
index 852a598ff7..1c0045aa0d 100644
--- a/src/tiled/tilesetdocument.cpp
+++ b/src/tiled/tilesetdocument.cpp
@@ -36,7 +36,6 @@
 #include <QUndoStack>
 
 namespace Tiled {
-namespace Internal {
 
 class ReloadTileset : public QUndoCommand
 {
@@ -400,5 +399,4 @@ void TilesetDocument::onWangSetRemoved(WangSet *wangSet)
     mWangColorModels.erase(wangSet);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetdocument.h b/src/tiled/tilesetdocument.h
index 17042afece..bcf58e98a1 100644
--- a/src/tiled/tilesetdocument.h
+++ b/src/tiled/tilesetdocument.h
@@ -32,7 +32,6 @@
 
 namespace Tiled {
 
-namespace Internal {
 
 class EditableTileset;
 class MapDocument;
@@ -80,7 +79,7 @@ class TilesetDocument : public Document
     void swapTileset(SharedTileset &tileset);
     const SharedTileset &tileset() const;
 
-    Q_INVOKABLE Tiled::Internal::EditableAsset *editable() override;
+    Q_INVOKABLE Tiled::EditableAsset *editable() override;
 
     bool isEmbedded() const;
     void setClean();
@@ -207,5 +206,4 @@ inline const QList<Tile *> &TilesetDocument::selectedTiles() const
     return mSelectedTiles;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetdocumentsmodel.cpp b/src/tiled/tilesetdocumentsmodel.cpp
index e4d8e34950..7c00dc104e 100644
--- a/src/tiled/tilesetdocumentsmodel.cpp
+++ b/src/tiled/tilesetdocumentsmodel.cpp
@@ -28,7 +28,6 @@
 #include <algorithm>
 
 namespace Tiled {
-namespace Internal {
 
 TilesetDocumentsModel::TilesetDocumentsModel(QObject *parent)
     : QAbstractListModel(parent)
@@ -135,5 +134,4 @@ bool TilesetDocumentsFilterModel::filterAcceptsRow(int sourceRow, const QModelIn
     return accepted;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetdocumentsmodel.h b/src/tiled/tilesetdocumentsmodel.h
index a0fa8cde9a..00f9d67ef8 100644
--- a/src/tiled/tilesetdocumentsmodel.h
+++ b/src/tiled/tilesetdocumentsmodel.h
@@ -31,8 +31,6 @@ namespace Tiled {
 
 class Tileset;
 
-namespace Internal {
-
 class MapDocument;
 
 /**
@@ -112,7 +110,6 @@ class TilesetDocumentsFilterModel : public QSortFilterProxyModel
     MapDocument *mMapDocument;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
 #endif // TILESETDOCUMENTSMODEL_H
diff --git a/src/tiled/tileseteditor.cpp b/src/tiled/tileseteditor.cpp
index a4b2317b7a..2ab6b89008 100644
--- a/src/tiled/tileseteditor.cpp
+++ b/src/tiled/tileseteditor.cpp
@@ -78,7 +78,6 @@ static const char SIZE_KEY[] = "TilesetEditor/Size";
 static const char STATE_KEY[] = "TilesetEditor/State";
 
 namespace Tiled {
-namespace Internal {
 
 namespace {
 
@@ -611,7 +610,7 @@ void TilesetEditor::retranslateUi()
     mRemoveTiles->setText(tr("Remove Tiles"));
     mShowAnimationEditor->setText(tr("Tile Animation Editor"));
 
-    mTileCollisionDock->toggleViewAction()->setShortcut(QCoreApplication::translate("Tiled::Internal::MainWindow", "Ctrl+Shift+O"));
+    mTileCollisionDock->toggleViewAction()->setShortcut(QCoreApplication::translate("Tiled::MainWindow", "Ctrl+Shift+O"));
 }
 
 static bool hasTileInTileset(const QUrl &imageSource, const Tileset &tileset)
@@ -1048,7 +1047,6 @@ void TilesetEditor::updateAddRemoveActions()
     mRemoveTiles->setEnabled(isCollection && hasSelection);
 }
 
-} // namespace Internal
 } // namespace Tiled
 
 #include "tileseteditor.moc"
diff --git a/src/tiled/tileseteditor.h b/src/tiled/tileseteditor.h
index 97b748e545..6022a732a4 100644
--- a/src/tiled/tileseteditor.h
+++ b/src/tiled/tileseteditor.h
@@ -41,8 +41,6 @@ class Terrain;
 class Tile;
 class Tileset;
 
-namespace Internal {
-
 class PropertiesDock;
 class TemplatesDock;
 class TerrainDock;
@@ -185,5 +183,4 @@ inline TileAnimationEditor *TilesetEditor::tileAnimationEditor() const
     return mTileAnimationEditor;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetmodel.cpp b/src/tiled/tilesetmodel.cpp
index 12b5b3013d..9cbbd132f9 100644
--- a/src/tiled/tilesetmodel.cpp
+++ b/src/tiled/tilesetmodel.cpp
@@ -29,7 +29,6 @@
 #include <QMimeData>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TilesetModel::TilesetModel(Tileset *tileset, QObject *parent):
     QAbstractListModel(parent),
diff --git a/src/tiled/tilesetmodel.h b/src/tiled/tilesetmodel.h
index d98c0a5015..5c437ba62d 100644
--- a/src/tiled/tilesetmodel.h
+++ b/src/tiled/tilesetmodel.h
@@ -28,7 +28,6 @@ namespace Tiled {
 class Tile;
 class Tileset;
 
-namespace Internal {
 
 /**
  * A model wrapping a tileset of a map. Used to display the tiles.
@@ -145,5 +144,4 @@ public slots:
     QList<int> mTileIds;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetparametersedit.cpp b/src/tiled/tilesetparametersedit.cpp
index 2ff8b84796..17dec4e330 100644
--- a/src/tiled/tilesetparametersedit.cpp
+++ b/src/tiled/tilesetparametersedit.cpp
@@ -31,7 +31,6 @@
 #include <QToolButton>
 
 namespace Tiled {
-namespace Internal {
 
 TilesetParametersEdit::TilesetParametersEdit(QWidget *parent)
     : QWidget(parent)
@@ -84,5 +83,4 @@ void TilesetParametersEdit::buttonClicked()
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetparametersedit.h b/src/tiled/tilesetparametersedit.h
index 572f6adc2c..ee7b4ca147 100644
--- a/src/tiled/tilesetparametersedit.h
+++ b/src/tiled/tilesetparametersedit.h
@@ -25,7 +25,6 @@
 class QLabel;
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetDocument;
 
@@ -56,5 +55,4 @@ inline TilesetDocument *TilesetParametersEdit::tilesetDocument() const
     return mTilesetDocument;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetterrainmodel.cpp b/src/tiled/tilesetterrainmodel.cpp
index 87cb6c559b..0915b7d1bf 100644
--- a/src/tiled/tilesetterrainmodel.cpp
+++ b/src/tiled/tilesetterrainmodel.cpp
@@ -27,7 +27,6 @@
 #include "tile.h"
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TilesetTerrainModel::TilesetTerrainModel(TilesetDocument *tilesetDocument,
                                          QObject *parent):
diff --git a/src/tiled/tilesetterrainmodel.h b/src/tiled/tilesetterrainmodel.h
index 5acbcc8098..6072e4dbc6 100644
--- a/src/tiled/tilesetterrainmodel.h
+++ b/src/tiled/tilesetterrainmodel.h
@@ -27,8 +27,6 @@ namespace Tiled {
 class Tileset;
 class Terrain;
 
-namespace Internal {
-
 class TilesetDocument;
 
 /**
@@ -114,5 +112,4 @@ class TilesetTerrainModel : public QAbstractListModel
     TilesetDocument *mTilesetDocument;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilesetview.cpp b/src/tiled/tilesetview.cpp
index 5173170230..30ae6fc6be 100644
--- a/src/tiled/tilesetview.cpp
+++ b/src/tiled/tilesetview.cpp
@@ -48,7 +48,6 @@
 #include <QtCore/qmath.h>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace {
 
diff --git a/src/tiled/tilesetview.h b/src/tiled/tilesetview.h
index 46481018ea..da0998291d 100644
--- a/src/tiled/tilesetview.h
+++ b/src/tiled/tilesetview.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class Terrain;
 
-namespace Internal {
-
 class TilesetDocument;
 class Zoomable;
 
@@ -206,7 +204,6 @@ inline bool TilesetView::markAnimatedTiles() const
     return mMarkAnimatedTiles;
 }
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::TilesetView *)
+Q_DECLARE_METATYPE(Tiled::TilesetView *)
diff --git a/src/tiled/tilesetwangsetmodel.cpp b/src/tiled/tilesetwangsetmodel.cpp
index e3a034b70f..bae9f07565 100644
--- a/src/tiled/tilesetwangsetmodel.cpp
+++ b/src/tiled/tilesetwangsetmodel.cpp
@@ -27,7 +27,6 @@
 #include "tile.h"
 
 using namespace Tiled;
-using namespace Internal;
 
 TilesetWangSetModel::TilesetWangSetModel(TilesetDocument *mapDocument,
                                          QObject *parent):
diff --git a/src/tiled/tilesetwangsetmodel.h b/src/tiled/tilesetwangsetmodel.h
index b8dd74f5cd..fb19ea9cee 100644
--- a/src/tiled/tilesetwangsetmodel.h
+++ b/src/tiled/tilesetwangsetmodel.h
@@ -28,8 +28,6 @@ class Tileset;
 class WangSet;
 class WangColor;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class TilesetWangSetModel : public QAbstractListModel
@@ -92,5 +90,4 @@ class TilesetWangSetModel : public QAbstractListModel
     TilesetDocument *mTilesetDocument;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestamp.cpp b/src/tiled/tilestamp.cpp
index 6b9b002538..44473f7ac4 100644
--- a/src/tiled/tilestamp.cpp
+++ b/src/tiled/tilestamp.cpp
@@ -29,7 +29,6 @@
 #include <QJsonArray>
 
 namespace Tiled {
-namespace Internal {
 
 class TileStampData : public QSharedData
 {
@@ -341,5 +340,4 @@ TileStamp TileStamp::fromJson(const QJsonObject &json, const QDir &mapDir)
     return stamp;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestamp.h b/src/tiled/tilestamp.h
index e5cfdafe7d..8d9968c78e 100644
--- a/src/tiled/tilestamp.h
+++ b/src/tiled/tilestamp.h
@@ -30,7 +30,6 @@
 #include <QVector>
 
 namespace Tiled {
-namespace Internal {
 
 struct TileStampVariation
 {
@@ -52,7 +51,6 @@ struct TileStampVariation
 
 class TileStampData;
 
-
 class TileStamp
 {
 public:
@@ -111,5 +109,4 @@ inline void TileStamp::addVariation(const TileStampVariation &variation)
     addVariation(variation.map->clone(), variation.probability);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestampmanager.cpp b/src/tiled/tilestampmanager.cpp
index 64f7499b37..64a5d4d20d 100644
--- a/src/tiled/tilestampmanager.cpp
+++ b/src/tiled/tilestampmanager.cpp
@@ -44,7 +44,6 @@
 #include <memory>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 static QString stampFilePath(const QString &name)
 {
diff --git a/src/tiled/tilestampmanager.h b/src/tiled/tilestampmanager.h
index de0edf6828..4538d69d2b 100644
--- a/src/tiled/tilestampmanager.h
+++ b/src/tiled/tilestampmanager.h
@@ -32,8 +32,6 @@ namespace Tiled {
 class Map;
 class TileLayer;
 
-namespace Internal {
-
 class MapDocument;
 class TileStamp;
 class TileStampModel;
@@ -117,5 +115,4 @@ inline TileStampModel *TileStampManager::tileStampModel() const
     return mTileStampModel;
 }
 
-} // namespace Tiled::Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestampmodel.cpp b/src/tiled/tilestampmodel.cpp
index bc9bb1d610..a3fa4ba4ca 100644
--- a/src/tiled/tilestampmodel.cpp
+++ b/src/tiled/tilestampmodel.cpp
@@ -23,7 +23,6 @@
 #include "minimaprenderer.h"
 
 namespace Tiled {
-namespace Internal {
 
 TileStampModel::TileStampModel(QObject *parent)
     : QAbstractItemModel(parent)
@@ -336,5 +335,4 @@ void TileStampModel::clear()
     endResetModel();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestampmodel.h b/src/tiled/tilestampmodel.h
index 9ce17a7e93..0a0d005a18 100644
--- a/src/tiled/tilestampmodel.h
+++ b/src/tiled/tilestampmodel.h
@@ -28,7 +28,6 @@ namespace Tiled {
 
 class Map;
 
-namespace Internal {
 
 struct TileStampVariation;
 
@@ -103,5 +102,4 @@ inline const QList<TileStamp> &TileStampModel::stamps() const
     return mStamps;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestampsdock.cpp b/src/tiled/tilestampsdock.cpp
index 770b293704..e097afc8ed 100644
--- a/src/tiled/tilestampsdock.cpp
+++ b/src/tiled/tilestampsdock.cpp
@@ -38,7 +38,6 @@
 #include <QVBoxLayout>
 
 namespace Tiled {
-namespace Internal {
 
 TileStampsDock::TileStampsDock(TileStampManager *stampManager, QWidget *parent)
     : QDockWidget(parent)
@@ -337,5 +336,4 @@ bool TileStampView::event(QEvent *event)
     return QTreeView::event(event);
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tilestampsdock.h b/src/tiled/tilestampsdock.h
index d41a454849..a338d20ff7 100644
--- a/src/tiled/tilestampsdock.h
+++ b/src/tiled/tilestampsdock.h
@@ -29,8 +29,6 @@ namespace Tiled {
 
 class TileLayer;
 
-namespace Internal {
-
 class TileStamp;
 class TileStampManager;
 class TileStampModel;
@@ -98,5 +96,4 @@ class TileStampView : public QTreeView
     bool event(QEvent *event) override;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/tmxmapformat.cpp b/src/tiled/tmxmapformat.cpp
index 5184e388fb..bb237c3bda 100644
--- a/src/tiled/tmxmapformat.cpp
+++ b/src/tiled/tmxmapformat.cpp
@@ -31,7 +31,6 @@
 #include <QXmlStreamReader>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 TmxMapFormat::TmxMapFormat(QObject *parent)
     : MapFormat(parent)
diff --git a/src/tiled/tmxmapformat.h b/src/tiled/tmxmapformat.h
index afcf5fa368..fee19f2e0a 100644
--- a/src/tiled/tmxmapformat.h
+++ b/src/tiled/tmxmapformat.h
@@ -29,7 +29,6 @@ namespace Tiled {
 class Tileset;
 class MapObject;
 
-namespace Internal {
 
 /**
  * A reader and writer for Tiled's .tmx map format.
@@ -130,5 +129,4 @@ class XmlObjectTemplateFormat : public ObjectTemplateFormat
     QString mError;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/toolmanager.cpp b/src/tiled/toolmanager.cpp
index 126b2cc45e..a04ce2106e 100644
--- a/src/tiled/toolmanager.cpp
+++ b/src/tiled/toolmanager.cpp
@@ -27,7 +27,6 @@
 #include <QShortcut>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 ToolManager::ToolManager(QObject *parent)
     : QObject(parent)
diff --git a/src/tiled/toolmanager.h b/src/tiled/toolmanager.h
index e7604df0a7..aea378551f 100644
--- a/src/tiled/toolmanager.h
+++ b/src/tiled/toolmanager.h
@@ -30,8 +30,6 @@ namespace Tiled {
 class Tile;
 class ObjectTemplate;
 
-namespace Internal {
-
 class AbstractTool;
 class MapDocument;
 
@@ -149,5 +147,4 @@ inline void ToolManager::setObjectTemplate(ObjectTemplate *objectTemplate)
     mObjectTemplate = objectTemplate;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/treeviewcombobox.cpp b/src/tiled/treeviewcombobox.cpp
index bbaf6651d9..0266ec46f0 100644
--- a/src/tiled/treeviewcombobox.cpp
+++ b/src/tiled/treeviewcombobox.cpp
@@ -28,7 +28,6 @@
 #include <QWheelEvent>
 
 namespace Tiled {
-namespace Internal {
 
 TreeViewComboBoxView::TreeViewComboBoxView(QWidget *parent)
     : QTreeView(parent)
@@ -170,5 +169,4 @@ TreeViewComboBoxView *TreeViewComboBox::view() const
     return m_view;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/treeviewcombobox.h b/src/tiled/treeviewcombobox.h
index 743ee1f959..377b513031 100644
--- a/src/tiled/treeviewcombobox.h
+++ b/src/tiled/treeviewcombobox.h
@@ -29,7 +29,6 @@
 #include <QTreeView>
 
 namespace Tiled {
-namespace Internal {
 
 class TreeViewComboBoxView : public QTreeView
 {
@@ -75,5 +74,4 @@ inline QModelIndex TreeViewComboBox::currentModelIndex() const
     return m_view->currentIndex();
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/undocommands.cpp b/src/tiled/undocommands.cpp
index 092f07c323..71cdaf6761 100644
--- a/src/tiled/undocommands.cpp
+++ b/src/tiled/undocommands.cpp
@@ -23,7 +23,6 @@
 #include <QUndoCommand>
 
 namespace Tiled {
-namespace Internal {
 
 bool cloneChildren(const QUndoCommand *command, QUndoCommand *parent)
 {
@@ -41,5 +40,4 @@ bool cloneChildren(const QUndoCommand *command, QUndoCommand *parent)
     return true;
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/undocommands.h b/src/tiled/undocommands.h
index ab49d451cd..65701a5e48 100644
--- a/src/tiled/undocommands.h
+++ b/src/tiled/undocommands.h
@@ -23,7 +23,6 @@
 class QUndoCommand;
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * These undo command IDs are used by Qt to determine whether two undo commands
@@ -55,5 +54,4 @@ class ClonableUndoCommand
 
 bool cloneChildren(const QUndoCommand *command, QUndoCommand *parent);
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/undodock.cpp b/src/tiled/undodock.cpp
index 3af3d351c7..7640f3b2f5 100644
--- a/src/tiled/undodock.cpp
+++ b/src/tiled/undodock.cpp
@@ -26,7 +26,6 @@
 #include <QVBoxLayout>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 UndoDock::UndoDock(QWidget *parent)
     : QDockWidget(parent)
diff --git a/src/tiled/undodock.h b/src/tiled/undodock.h
index 784c150c91..418521ccde 100644
--- a/src/tiled/undodock.h
+++ b/src/tiled/undodock.h
@@ -27,7 +27,6 @@ class QUndoStack;
 class QUndoView;
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * A dock widget showing the undo stack. Mainly for debugging, but can also be
@@ -50,5 +49,4 @@ class UndoDock : public QDockWidget
     QUndoView *mUndoView;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/utils.cpp b/src/tiled/utils.cpp
index b8a42b35bb..4fb86505a1 100644
--- a/src/tiled/utils.cpp
+++ b/src/tiled/utils.cpp
@@ -120,7 +120,7 @@ void restoreGeometry(QWidget *widget)
 {
     Q_ASSERT(!widget->objectName().isEmpty());
 
-    const QSettings *settings = Internal::Preferences::instance()->settings();
+    const QSettings *settings = Preferences::instance()->settings();
 
     const QString key = widget->objectName() + QLatin1String("/Geometry");
     widget->restoreGeometry(settings->value(key).toByteArray());
@@ -139,7 +139,7 @@ void saveGeometry(QWidget *widget)
 {
     Q_ASSERT(!widget->objectName().isEmpty());
 
-    QSettings *settings = Internal::Preferences::instance()->settings();
+    QSettings *settings = Preferences::instance()->settings();
 
     const QString key = widget->objectName() + QLatin1String("/Geometry");
     settings->setValue(key, widget->saveGeometry());
diff --git a/src/tiled/varianteditorfactory.cpp b/src/tiled/varianteditorfactory.cpp
index 70da7a31d9..44f1560ceb 100644
--- a/src/tiled/varianteditorfactory.cpp
+++ b/src/tiled/varianteditorfactory.cpp
@@ -33,7 +33,6 @@
 #include <QToolButton>
 
 namespace Tiled {
-namespace Internal {
 
 class ResetWidget : public QWidget
 {
@@ -279,7 +278,6 @@ void VariantEditorFactory::slotEditorDestroyed(QObject *object)
     }
 }
 
-} // namespace Internal
 } // namespace Tiled
 
 #include "varianteditorfactory.moc"
diff --git a/src/tiled/varianteditorfactory.h b/src/tiled/varianteditorfactory.h
index da89dd76d2..4d5f4b7d3e 100644
--- a/src/tiled/varianteditorfactory.h
+++ b/src/tiled/varianteditorfactory.h
@@ -24,7 +24,6 @@
 #include <QtVariantEditorFactory>
 
 namespace Tiled {
-namespace Internal {
 
 class FileEdit;
 class TextPropertyEdit;
@@ -78,5 +77,4 @@ private slots:
     QMap<TextPropertyEdit *, QtProperty *> mTextPropertyEditToProperty;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/variantpropertymanager.cpp b/src/tiled/variantpropertymanager.cpp
index 3c84ae4463..8ee47382d2 100644
--- a/src/tiled/variantpropertymanager.cpp
+++ b/src/tiled/variantpropertymanager.cpp
@@ -28,21 +28,18 @@
 #include <QFileInfo>
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetParametersPropertyType {};
 class AlignmentPropertyType {};
 
 } // namespace Tiled
-} // namespace Internal
 
 // Needs to be up here rather than at the bottom of the file to make a
 // static_assert in qMetaTypeId work (as of C++11)
-Q_DECLARE_METATYPE(Tiled::Internal::TilesetParametersPropertyType)
-Q_DECLARE_METATYPE(Tiled::Internal::AlignmentPropertyType)
+Q_DECLARE_METATYPE(Tiled::TilesetParametersPropertyType)
+Q_DECLARE_METATYPE(Tiled::AlignmentPropertyType)
 
 namespace Tiled {
-namespace Internal {
 
 VariantPropertyManager::VariantPropertyManager(QObject *parent)
     : QtVariantPropertyManager(parent)
@@ -435,5 +432,4 @@ QString VariantPropertyManager::indexVToString(int idx) const
     return tr("Center");
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/variantpropertymanager.h b/src/tiled/variantpropertymanager.h
index 10fdaeef6c..9effc680ad 100644
--- a/src/tiled/variantpropertymanager.h
+++ b/src/tiled/variantpropertymanager.h
@@ -26,7 +26,6 @@
 #include <QFileIconProvider>
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * Extension of the QtVariantPropertyManager that adds support for a filePath
@@ -99,5 +98,4 @@ private slots:
     QFileIconProvider mIconProvider;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangbrush.cpp b/src/tiled/wangbrush.cpp
index f475fc3ee2..f1ee1f5dc4 100644
--- a/src/tiled/wangbrush.cpp
+++ b/src/tiled/wangbrush.cpp
@@ -35,7 +35,6 @@
 #include <QtMath>
 
 using namespace Tiled;
-using namespace Internal;
 
 //value between 0 and 0.5 to control the dead zone with edge mode.
 static const double MIDDLE_DEAD_ZONE = 0.25;
diff --git a/src/tiled/wangbrush.h b/src/tiled/wangbrush.h
index d414ad9d7f..bc3854cdb2 100644
--- a/src/tiled/wangbrush.h
+++ b/src/tiled/wangbrush.h
@@ -24,7 +24,6 @@
 #include "wangset.h"
 
 namespace Tiled {
-namespace Internal {
 
 class WangBrush : public AbstractTileTool
 {
@@ -96,5 +95,4 @@ public slots:
     BrushBehavior mBrushBehavior;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangcolormodel.cpp b/src/tiled/wangcolormodel.cpp
index 458692231f..47a4eb57e2 100644
--- a/src/tiled/wangcolormodel.cpp
+++ b/src/tiled/wangcolormodel.cpp
@@ -30,7 +30,6 @@
 #include <QPalette>
 
 using namespace Tiled;
-using namespace Internal;
 
 WangColorModel::WangColorModel(TilesetDocument *tilesetDocument,
                                WangSet *wangSet,
diff --git a/src/tiled/wangcolormodel.h b/src/tiled/wangcolormodel.h
index b81e33463b..1008c7e30f 100644
--- a/src/tiled/wangcolormodel.h
+++ b/src/tiled/wangcolormodel.h
@@ -28,8 +28,6 @@ namespace Tiled {
 
 class Tileset;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class WangColorModel : public QAbstractItemModel
@@ -92,5 +90,4 @@ class WangColorModel : public QAbstractItemModel
     WangSet *mWangSet;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangcolorview.cpp b/src/tiled/wangcolorview.cpp
index 4fb799bcb0..42aee48ebd 100644
--- a/src/tiled/wangcolorview.cpp
+++ b/src/tiled/wangcolorview.cpp
@@ -31,7 +31,6 @@
 #include <QSortFilterProxyModel>
 
 using namespace Tiled;
-using namespace Internal;
 
 namespace {
 
diff --git a/src/tiled/wangcolorview.h b/src/tiled/wangcolorview.h
index ae09ac8454..81a5cfb381 100644
--- a/src/tiled/wangcolorview.h
+++ b/src/tiled/wangcolorview.h
@@ -26,8 +26,6 @@ namespace Tiled {
 
 class WangColor;
 
-namespace Internal {
-
 class WangColorView : public QTreeView
 {
     Q_OBJECT
@@ -50,5 +48,4 @@ private slots:
     QSharedPointer<WangColor> mClickedWangColor;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangdock.cpp b/src/tiled/wangdock.cpp
index 454b4b6bf7..f656483cb3 100644
--- a/src/tiled/wangdock.cpp
+++ b/src/tiled/wangdock.cpp
@@ -48,10 +48,8 @@
 #include <QUndoStack>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 namespace Tiled {
-namespace Internal {
 
 static WangSet *firstWangSet(MapDocument *MapDocument)
 {
@@ -98,7 +96,6 @@ class HasChildrenFilterModel : public QSortFilterProxyModel
     bool mEnabled;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
 WangDock::WangDock(QWidget *parent)
diff --git a/src/tiled/wangdock.h b/src/tiled/wangdock.h
index 8ac90e9065..2e6cc3b747 100644
--- a/src/tiled/wangdock.h
+++ b/src/tiled/wangdock.h
@@ -32,7 +32,6 @@ class QToolBar;
 class QTreeView;
 
 namespace Tiled {
-namespace Internal {
 
 class Document;
 class HasChildrenFilterModel;
@@ -133,5 +132,4 @@ private slots:
     bool mInitializing;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangfiller.cpp b/src/tiled/wangfiller.cpp
index 6e94a91ef0..7303a640b9 100644
--- a/src/tiled/wangfiller.cpp
+++ b/src/tiled/wangfiller.cpp
@@ -26,7 +26,6 @@
 #include "wangset.h"
 
 using namespace Tiled;
-using namespace Internal;
 
 static const QPoint aroundTilePoints[] = {
     QPoint( 0, -1),
diff --git a/src/tiled/wangfiller.h b/src/tiled/wangfiller.h
index c9912509db..149c13796a 100644
--- a/src/tiled/wangfiller.h
+++ b/src/tiled/wangfiller.h
@@ -33,8 +33,6 @@ namespace Tiled {
 
 class StaggeredRenderer;
 
-namespace Internal {
-
 /**
  * WangFiller provides functions for choosing cells based on a surrounding map
  * and a wangSet.
@@ -108,5 +106,4 @@ class WangFiller
     Map::StaggerAxis mStaggerAxis;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangsetmodel.cpp b/src/tiled/wangsetmodel.cpp
index 7bd98c0053..d9f78f5611 100644
--- a/src/tiled/wangsetmodel.cpp
+++ b/src/tiled/wangsetmodel.cpp
@@ -36,7 +36,6 @@
 #include <QPalette>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 WangSetModel::WangSetModel(QAbstractItemModel *tilesetDocumentModel,
                            QObject *parent):
diff --git a/src/tiled/wangsetmodel.h b/src/tiled/wangsetmodel.h
index 7946c7c35c..3265549e5f 100644
--- a/src/tiled/wangsetmodel.h
+++ b/src/tiled/wangsetmodel.h
@@ -28,8 +28,6 @@ namespace Tiled {
 class Tileset;
 class WangSet;
 
-namespace Internal {
-
 class TilesetDocument;
 
 class WangSetModel : public QAbstractItemModel
@@ -81,5 +79,4 @@ private slots:
     QList<TilesetDocument*> mTilesetDocuments;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangsetview.cpp b/src/tiled/wangsetview.cpp
index f692b0566a..e184e3311e 100644
--- a/src/tiled/wangsetview.cpp
+++ b/src/tiled/wangsetview.cpp
@@ -36,7 +36,6 @@
 #include <QWheelEvent>
 
 using namespace Tiled;
-using namespace Tiled::Internal;
 
 WangSetView::WangSetView(QWidget *parent)
     : QTreeView(parent)
diff --git a/src/tiled/wangsetview.h b/src/tiled/wangsetview.h
index 9db2b046f3..be7d093f85 100644
--- a/src/tiled/wangsetview.h
+++ b/src/tiled/wangsetview.h
@@ -23,7 +23,6 @@
 #include <QTreeView>
 
 namespace Tiled {
-namespace Internal {
 
 class TilesetDocument;
 class Zoomable;
@@ -56,7 +55,6 @@ private slots:
     TilesetDocument *mTilesetDocument;
 };
 
-} // namespace Internal
 } // namespace Tiled
 
-Q_DECLARE_METATYPE(Tiled::Internal::WangSetView *)
+Q_DECLARE_METATYPE(Tiled::WangSetView *)
diff --git a/src/tiled/wangtemplatemodel.cpp b/src/tiled/wangtemplatemodel.cpp
index 91c5bffc88..ed43678aa2 100644
--- a/src/tiled/wangtemplatemodel.cpp
+++ b/src/tiled/wangtemplatemodel.cpp
@@ -23,7 +23,6 @@
 #include <QtMath>
 
 using namespace Tiled;
-using namespace Internal;
 
 WangTemplateModel::WangTemplateModel(WangSet *wangSet, QObject *parent)
     : QAbstractListModel(parent)
diff --git a/src/tiled/wangtemplatemodel.h b/src/tiled/wangtemplatemodel.h
index 096f976832..8ace65b962 100644
--- a/src/tiled/wangtemplatemodel.h
+++ b/src/tiled/wangtemplatemodel.h
@@ -26,7 +26,6 @@
 
 namespace Tiled {
 
-namespace Internal {
 
 /**
  * A model for getting the info for a wang set template of a given WangSet
@@ -62,5 +61,4 @@ public slots:
     WangSet *mWangSet;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/wangtemplateview.cpp b/src/tiled/wangtemplateview.cpp
index bb97e17fae..aa0cfa0fbb 100644
--- a/src/tiled/wangtemplateview.cpp
+++ b/src/tiled/wangtemplateview.cpp
@@ -36,7 +36,6 @@
 #include <QWheelEvent>
 
 using namespace Tiled;
-using namespace Internal;
 
 namespace {
 /* The delegate for drawing the wang tile templates
diff --git a/src/tiled/wangtemplateview.h b/src/tiled/wangtemplateview.h
index 6c7bde37ce..e0885bf9b5 100644
--- a/src/tiled/wangtemplateview.h
+++ b/src/tiled/wangtemplateview.h
@@ -29,8 +29,6 @@ namespace Tiled {
 class WangSet;
 class WangId;
 
-namespace Internal {
-
 class Zoomable;
 
 class WangTemplateView : public QListView
@@ -65,5 +63,4 @@ private slots:
     Zoomable *mZoomable;
 };
 
-}
-}
+} // namespace Tiled
diff --git a/src/tiled/winsparkleautoupdater.cpp b/src/tiled/winsparkleautoupdater.cpp
index db571ae1a2..d6442b0ab4 100644
--- a/src/tiled/winsparkleautoupdater.cpp
+++ b/src/tiled/winsparkleautoupdater.cpp
@@ -25,7 +25,6 @@
 #include <winsparkle.h>
 
 namespace Tiled {
-namespace Internal {
 
 #ifdef TILED_SNAPSHOT
 
@@ -85,5 +84,4 @@ QDateTime WinSparkleAutoUpdater::lastUpdateCheckDate()
 #endif
 }
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/winsparkleautoupdater.h b/src/tiled/winsparkleautoupdater.h
index 9c96469659..d49db91d5b 100644
--- a/src/tiled/winsparkleautoupdater.h
+++ b/src/tiled/winsparkleautoupdater.h
@@ -23,7 +23,6 @@
 #include "autoupdater.h"
 
 namespace Tiled {
-namespace Internal {
 
 class WinSparkleAutoUpdater : public AutoUpdater
 {
@@ -37,5 +36,4 @@ class WinSparkleAutoUpdater : public AutoUpdater
     QDateTime lastUpdateCheckDate() override;
 };
 
-} // namespace Internal
 } // namespace Tiled
diff --git a/src/tiled/zoomable.cpp b/src/tiled/zoomable.cpp
index f357561b72..84435cecef 100644
--- a/src/tiled/zoomable.cpp
+++ b/src/tiled/zoomable.cpp
@@ -27,7 +27,9 @@
 
 #include <cmath>
 
-using namespace Tiled::Internal;
+#include "qtcompat_p.h"
+
+using namespace Tiled;
 
 static QString scaleToString(qreal scale)
 {
@@ -126,7 +128,7 @@ void Zoomable::handlePinchGesture(QPinchGesture *pinch)
         break;
     case Qt::GestureStarted:
         mGestureStartScale = mScale;
-        // fall through
+        Q_FALLTHROUGH();
     case Qt::GestureUpdated: {
         qreal factor = pinch->totalScaleFactor();
         qreal scale = qBound(mZoomFactors.first(),
diff --git a/src/tiled/zoomable.h b/src/tiled/zoomable.h
index 0b96bf984c..d589f586ac 100644
--- a/src/tiled/zoomable.h
+++ b/src/tiled/zoomable.h
@@ -29,7 +29,6 @@ class QPinchGesture;
 class QRegExpValidator;
 
 namespace Tiled {
-namespace Internal {
 
 /**
  * This class represents something zoomable. Is has a zoom factor and methods
@@ -100,5 +99,4 @@ private slots:
     QRegExpValidator *mComboValidator;
 };
 
-} // namespace Internal
 } // namespace Tiled