Edmond and Kent, thanks for the patch.  Ezio, thanks for re-opening.

After testing the patch with and without 'Editor', I preferred without. It is slightly redundant and noisy, especially when editing EditorWindow.py ;-). Also, Windows 7 stacks icons for windows belonging to a program under the program icon on the task bar. When the mouse is over the program icon, it pop up a window of *limited* width listing the window titles. The popup is narrow enough that paths to Idle test files in my repository clone get truncated when 'Editor' is added.

I suspect that adding '''else: filename = "Untitled"''' to short_title() makes the corresponding '''else: title = "Untitled"''' in saved_change_hook() useless. I will check later for possible removal.

Since I sometimes have multiple Find in File Output windows, I would like to expand their titles also. Since the Python version is irrelevant. I am thinking of
  Python: Matches for "<re>"
But I think their may be other uses of Output windows (easily found by searching for "Output" ;-).  In any case, extensions and new features should be free to use use OutputWindow. So we cannot generically modify OutputWindow.short_title . If the self parameter of short_title does not somehow indicate that the output is for Find in Files, we can subclass and over-ride.

class FiFWindow(OutputWindow):
  def short_title(self):
    return <fif title>