Issue #12590: IDLE editor window now always displays the first line
when opening a long file.  With Tk 8.5, the first line was hidden.
diff --git a/Lib/idlelib/IOBinding.py b/Lib/idlelib/IOBinding.py
index 3f5d556..d20c708 100644
--- a/Lib/idlelib/IOBinding.py
+++ b/Lib/idlelib/IOBinding.py
@@ -232,7 +232,7 @@
             # before being able to execute the code
             self.set_saved(False)
         self.text.mark_set("insert", "1.0")
-        self.text.see("insert")
+        self.text.yview("insert")
         self.updaterecentfileslist(filename)
         return True