Issue #27611: Fixed support of default root window in the Tix module.
diff --git a/Lib/lib-tk/Tix.py b/Lib/lib-tk/Tix.py
index 50938cc..a7b785e 100644
--- a/Lib/lib-tk/Tix.py
+++ b/Lib/lib-tk/Tix.py
@@ -477,10 +477,14 @@
     (multiple) Display Items"""
 
     def __init__(self, itemtype, cnf={}, **kw):
-        master = Tkinter._default_root
-        if not master and 'refwindow' in cnf: master=cnf['refwindow']
-        elif not master and 'refwindow' in kw:  master= kw['refwindow']
-        elif not master: raise RuntimeError, "Too early to create display style: no root window"
+        if 'refwindow' in kw:
+            master = kw['refwindow']
+        elif 'refwindow' in cnf:
+            master = cnf['refwindow']
+        else:
+            master = Tkinter._default_root
+            if not master:
+                raise RuntimeError("Too early to create display style: no root window")
         self.tk = master.tk
         self.stylename = self.tk.call('tixDisplayStyle', itemtype,
                             *self._options(cnf,kw) )