Index: src/org/openstreetmap/josm/gui/dialogs/ToggleDialog.java
===================================================================
--- src/org/openstreetmap/josm/gui/dialogs/ToggleDialog.java	(Revision 1986)
+++ src/org/openstreetmap/josm/gui/dialogs/ToggleDialog.java	(Arbeitskopie)
@@ -166,7 +166,9 @@
                 catch (SecurityException e1) {
                     System.out.println(tr("Warning: failed to put toggle dialog always on top. Exception was: {0}", e1.toString()));
                 }
-                parent.remove(ToggleDialog.this);
+                if (parent != null) {
+                    parent.remove(ToggleDialog.this);
+                }
                 f.getContentPane().add(ToggleDialog.this);
                 f.addWindowListener((winadapter = new WindowAdapter(){
                     @Override public void windowClosing(WindowEvent e) {
@@ -176,7 +178,9 @@
 
                         // doLayout() - workaround
                         setVisible(false);
-                        parent.add(ToggleDialog.this);
+                        if (parent != null) {
+                            parent.add(ToggleDialog.this);
+                        }
                         if(Main.pref.getBoolean(action.prefname+".visible")) {
                             setVisible(true);
                         }
@@ -203,8 +207,10 @@
                 titleBar.setVisible(false);
 
                 // doLayout() - workaround
-                parent.setVisible(false);
-                parent.setVisible(true);
+                if (parent != null) {
+                    parent.setVisible(false);
+                    parent.setVisible(true);
+                }
             }
         };
         sticky.addActionListener(stickyActionListener);