Get rid of conflicting ^X binding.  Use ^W.
diff --git a/Tools/idle/EditorWindow.py b/Tools/idle/EditorWindow.py
index 1b9db06..fc8a8f1 100644
--- a/Tools/idle/EditorWindow.py
+++ b/Tools/idle/EditorWindow.py
@@ -45,6 +45,7 @@
         self.text.bind("<<help>>", self.help_dialog)
         self.text.bind("<<about-idle>>", self.about_dialog)
         self.text.bind("<<open-module>>", self.open_module)
+        self.text.bind("<<do-nothing>>", lambda event: "break")
 
         vbar['command'] = text.yview
         vbar.pack(side=RIGHT, fill=Y)