Index: /applications/editors/josm/plugins/openstreetbugs/src/org/openstreetmap/josm/plugins/osb/OsbPlugin.java
===================================================================
--- /applications/editors/josm/plugins/openstreetbugs/src/org/openstreetmap/josm/plugins/osb/OsbPlugin.java	(revision 25517)
+++ /applications/editors/josm/plugins/openstreetbugs/src/org/openstreetmap/josm/plugins/osb/OsbPlugin.java	(revision 25518)
@@ -240,5 +240,5 @@
     }
 
-    private void updateLayer(DataSet osbData) {
+    private synchronized void updateLayer(DataSet osbData) {
         if(layer == null) {
             layer = new OsbLayer(osbData, "OpenStreetBugs", dialog);
@@ -262,6 +262,4 @@
     public void layerRemoved(Layer oldLayer) {
         if(oldLayer == layer) {
-            MapView.removeLayerChangeListener(this);
-            MapView.removeLayerChangeListener(dialog);
             layer = null;
         }