have to-do preferences set to "Show only due items" (checked) which
means futre dated items are not shown.

If I do a find and find a future dated to-do and click on that to-do
to edit this then my preference seems to be changed show all future items

The only way I can shrink the list back to due items is to go back to
Tools- Preferences (where I find that "Show only due items" is still
(checked) - once I click OK the list shrinks back to showing only due

Is there a quicker way to get back to the requested default view after doing a search.

Another question:
Are there any other Add-ins available like "Delete Duplicates" where
does one go to search for Addins?

Thanks very much