diff --git a/src/plugins/coreplugin/icore.cpp b/src/plugins/coreplugin/icore.cpp
index 1df14f631b0..1c2a1a0dc8d 100644
--- a/src/plugins/coreplugin/icore.cpp
+++ b/src/plugins/coreplugin/icore.cpp
@@ -1216,7 +1216,7 @@ void ICorePrivate::init()
 
     QApplication::setStyle(new ManhattanStyle(baseName));
 
-    m_modeManager = new ModeManager(m_mainwindow, m_modeStack);
+    m_modeManager = new ModeManager(m_modeStack);
     connect(m_modeStack, &FancyTabWidget::topAreaClicked, this, [](Qt::MouseButton, Qt::KeyboardModifiers modifiers) {
         if (modifiers & Qt::ShiftModifier) {
             QColor color = QColorDialog::getColor(StyleHelper::requestedBaseColor(), ICore::dialogParent());
diff --git a/src/plugins/coreplugin/modemanager.cpp b/src/plugins/coreplugin/modemanager.cpp
index 80ecfc004df..cebc5f8422d 100644
--- a/src/plugins/coreplugin/modemanager.cpp
+++ b/src/plugins/coreplugin/modemanager.cpp
@@ -68,7 +68,6 @@ struct ModeManagerPrivate
     void activateModeHelper(Id id);
     void extensionsInitializedHelper();
 
-    Internal::MainWindow *m_mainWindow;
     Internal::FancyTabWidget *m_modeStack;
     Internal::FancyActionBar *m_actionBar;
     QMap<QAction*, int> m_actions;
@@ -101,12 +100,10 @@ void ModeManagerPrivate::showMenu(int index, QMouseEvent *event)
     m_modes.at(index)->menu()->popup(event->globalPosition().toPoint());
 }
 
-ModeManager::ModeManager(Internal::MainWindow *mainWindow,
-                         Internal::FancyTabWidget *modeStack)
+ModeManager::ModeManager(Internal::FancyTabWidget *modeStack)
 {
     m_instance = this;
     d = new ModeManagerPrivate();
-    d->m_mainWindow = mainWindow;
     d->m_modeStack = modeStack;
     d->m_oldCurrent = -1;
     d->m_actionBar = new Internal::FancyActionBar(modeStack);
diff --git a/src/plugins/coreplugin/modemanager.h b/src/plugins/coreplugin/modemanager.h
index 9ec8812ad8d..a4a1a26ebc3 100644
--- a/src/plugins/coreplugin/modemanager.h
+++ b/src/plugins/coreplugin/modemanager.h
@@ -21,7 +21,6 @@ class IMode;
 namespace Internal {
 class FancyTabWidget;
 class ICorePrivate;
-class MainWindow;
 }
 
 class CORE_EXPORT ModeManager : public QObject
@@ -60,7 +59,7 @@ signals:
     void currentModeChanged(Utils::Id mode, Utils::Id oldMode = {});
 
 private:
-    explicit ModeManager(Internal::MainWindow *mainWindow, Internal::FancyTabWidget *modeStack);
+    explicit ModeManager(Internal::FancyTabWidget *modeStack);
     ~ModeManager() override;
 
     static void extensionsInitialized();
@@ -71,7 +70,6 @@ private:
 
     friend class ICore;
     friend class IMode;
-    friend class Internal::MainWindow;
     friend class Internal::ICorePrivate;
 };