Index: trunk/src/org/openstreetmap/josm/Main.java
===================================================================
--- trunk/src/org/openstreetmap/josm/Main.java	(revision 12127)
+++ trunk/src/org/openstreetmap/josm/Main.java	(revision 12128)
@@ -38,5 +38,4 @@
 import javax.swing.JComponent;
 import javax.swing.JOptionPane;
-import javax.swing.JPanel;
 import javax.swing.KeyStroke;
 import javax.swing.LookAndFeel;
@@ -208,4 +207,9 @@
 
     /**
+     * The private content pane of {@code MainFrame}, required to be static for shortcut handling.
+     */
+    protected static JComponent contentPanePrivate;
+
+    /**
      * The file watcher service.
      */
@@ -637,6 +641,4 @@
         }
     }
-
-    protected static final JPanel contentPanePrivate = new JPanel(new BorderLayout());
 
     public static void redirectToMainContentPane(JComponent source) {
@@ -770,5 +772,4 @@
         }
         toolbar = new ToolbarPreferences();
-        contentPanePrivate.updateUI();
 
         UIManager.put("OptionPane.okIcon", ImageProvider.get("ok"));
Index: trunk/src/org/openstreetmap/josm/gui/MainApplication.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/MainApplication.java	(revision 12127)
+++ trunk/src/org/openstreetmap/josm/gui/MainApplication.java	(revision 12128)
@@ -38,4 +38,5 @@
 
 import javax.net.ssl.SSLSocketFactory;
+import javax.swing.JComponent;
 import javax.swing.JOptionPane;
 import javax.swing.RepaintManager;
@@ -313,5 +314,6 @@
                 args.getSingle(Option.GEOMETRY).orElse(null),
                 !args.hasOption(Option.NO_MAXIMIZE) && Main.pref.getBoolean("gui.maximized", false));
-        final MainFrame mainFrame = new MainFrame(contentPanePrivate, geometry);
+        final MainFrame mainFrame = new MainFrame(geometry);
+        Main.contentPanePrivate = (JComponent) mainFrame.getContentPane();
         Main.mainPanel = mainFrame.getPanel();
         Main.parent = mainFrame;
Index: trunk/src/org/openstreetmap/josm/gui/MainFrame.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/MainFrame.java	(revision 12127)
+++ trunk/src/org/openstreetmap/josm/gui/MainFrame.java	(revision 12128)
@@ -6,5 +6,4 @@
 import java.awt.BorderLayout;
 import java.awt.Component;
-import java.awt.Container;
 import java.awt.Image;
 import java.awt.Rectangle;
@@ -56,18 +55,17 @@
      */
     public MainFrame() {
-        this(new JPanel(), new WindowGeometry(new Rectangle(10, 10, 500, 500)));
-    }
-
-    /**
-     * Create a new main window. The parameters will be removed in the future.
-     * @param contentPanePrivate The content
+        this(new WindowGeometry(new Rectangle(10, 10, 500, 500)));
+    }
+
+    /**
+     * Create a new main window. The parameter will be removed in the future.
      * @param geometry The inital geometry to use.
-     * @since 11713
-     */
-    public MainFrame(Container contentPanePrivate, WindowGeometry geometry) {
+     * @since 12127
+     */
+    public MainFrame(WindowGeometry geometry) {
         super();
         this.geometry = geometry;
         this.panel = new MainPanel(Main.getLayerManager());
-        setContentPane(contentPanePrivate);
+        setContentPane(new JPanel(new BorderLayout()));
     }