Fix for https://bugs.eclipse.org/bugs/show_bug.cgi?id=272780.
diff --git a/jsf/plugins/org.eclipse.jst.pagedesigner/src/org/eclipse/jst/pagedesigner/editors/HTMLEditor.java b/jsf/plugins/org.eclipse.jst.pagedesigner/src/org/eclipse/jst/pagedesigner/editors/HTMLEditor.java
index d696e50..35d84d8 100644
--- a/jsf/plugins/org.eclipse.jst.pagedesigner/src/org/eclipse/jst/pagedesigner/editors/HTMLEditor.java
+++ b/jsf/plugins/org.eclipse.jst.pagedesigner/src/org/eclipse/jst/pagedesigner/editors/HTMLEditor.java
@@ -901,7 +901,8 @@
 
 	private IPropertySheetPage getPropertySheetPage()
     {
-        if (_tabbedPropSheet == null)
+        if (_tabbedPropSheet == null || _tabbedPropSheet.getControl() == null 
+                || _tabbedPropSheet.getControl().isDisposed())
         {
             IPropertySheetPageFactory factory = getPageFactory();
             if (factory != null)