Index: trunk/src/org/openstreetmap/josm/gui/MapFrame.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/MapFrame.java	(revision 16130)
+++ trunk/src/org/openstreetmap/josm/gui/MapFrame.java	(revision 16132)
@@ -343,4 +343,5 @@
         MainApplication.getLayerManager().removeActiveLayerChangeListener(this);
         MainApplication.getMenu().modeMenu.removeAll();
+        rememberToggleDialogWidth();
         dialogsPanel.destroy();
         Config.getPref().removePreferenceChangeListener(sidetoolbarPreferencesChangedListener);
@@ -739,5 +740,5 @@
     public void rememberToggleDialogWidth() {
         if (dialogsPanel.isVisible()) {
-            TOGGLE_DIALOGS_WIDTH.put(splitPane.getWidth() - splitPane.getDividerLocation());
+            TOGGLE_DIALOGS_WIDTH.put(splitPane.getWidth() - splitPane.getDividerLocation() - splitPane.getDividerSize() - 1);
         }
     }