diff -r ec153828ded2 -r b789b695b5c6 dialogs/SFCStepDialog.py
--- a/dialogs/SFCStepDialog.py	Tue Aug 15 12:17:51 2017 +0300
+++ b/dialogs/SFCStepDialog.py	Tue Aug 15 15:50:30 2017 +0300
@@ -47,7 +47,7 @@
         @param tagname: Tagname of project POU edited
         @param initial: True if step is initial (default: False)
         """
-        BlockPreviewDialog.__init__(self,parent, controller, tagname,
+        BlockPreviewDialog.__init__(self, parent, controller, tagname,
               title=_('Edit Step'))
 
         # Init common sizers