Index: /trunk/src/org/openstreetmap/josm/gui/dialogs/ToggleDialog.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/dialogs/ToggleDialog.java	(revision 5030)
+++ /trunk/src/org/openstreetmap/josm/gui/dialogs/ToggleDialog.java	(revision 5031)
@@ -667,5 +667,7 @@
         PROP_BUTTON_HIDING.put(val);
         buttonsHide.setIcon(ImageProvider.get("misc", val != ButtonHiddingType.ALWAYS_SHOWN ? "buttonhide" : "buttonshow"));
-        buttonsPanel.setVisible(val != ButtonHiddingType.ALWAYS_HIDDEN);
+        if (buttonsPanel != null) {
+            buttonsPanel.setVisible(val != ButtonHiddingType.ALWAYS_HIDDEN);
+        }
         stateChanged();
     }