--- a/AbstractHierarchicalItem.st	Mon Jul 30 14:28:50 2018 +0200
+++ b/AbstractHierarchicalItem.st	Mon Jul 30 17:19:20 2018 +0200
@@ -966,15 +966,15 @@
         self makeWidthAndHeightUnknown
     ].
 
-    (model := self model) notNil ifTrue:[
-        model synchronized:[
+    self synchronized:[
+        (model := self model) notNil ifTrue:[
             model itemChanged:what with:anArgument from:self.
         ].
     ].
     super changed:what with:anArgument
 
     "Modified: / 24-11-2010 / 17:21:20 / cg"
-    "Modified: / 30-07-2018 / 14:25:45 / Stefan Vogel"
+    "Modified: / 30-07-2018 / 15:58:18 / Stefan Vogel"
 !
 
 childrenOrderChanged