diff --git a/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java b/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java
index 762b24ef5..42fbba18b 100644
--- a/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java
+++ b/sdk/jme3-materialeditor/src/com/jme3/gde/materialdefinition/editor/MatDefEditorlElement.java
@@ -272,6 +272,11 @@ public final class MatDefEditorlElement extends JPanel implements MultiViewEleme
 
     protected void selectionChanged(Selectable selectable) {
         MatDefNavigatorPanel nav = obj.getLookup().lookup(MatDefNavigatorPanel.class);
+        //It's possible that the navigator is null if it's collapsed in the ui.
+        //In that case we early return to avoid further issues
+        if(nav == null){
+            return;
+        }
         try {
             Node n = findNode(nav.getExplorerManager().getRootContext(), selectable.getKey());
             if (n == null) {