Message 265189 - Python tracker

using this as a work-around, not tested with Tcl/Tk 8.5 or older.

--- a/Lib/idlelib/configDialog.py
+++ b/Lib/idlelib/configDialog.py
@@ -113,7 +113,11 @@ class ConfigDialog(Toplevel):
 
     def CreatePageFontTab(self):
         parent = self.parent
-        self.fontSize = StringVar(parent)
+        # see issue #26673
+        if TkVersion >= 8.6:
+            self.fontSize = IntVar(parent)
+        else:
+            self.fontSize = StringVar(parent)
         self.fontBold = BooleanVar(parent)
         self.fontName = StringVar(parent)
         self.spaceNum = IntVar(parent)