widont not working when applied to the output of a Redactor field

[petehjfd]

I have a Redactor field containing multiple paragraphs. In the template I have:

{{ entry.body | widont }}

No   is being added anywhere.

If I replace the Redactor output with some hardcoded text, it works fine:

{{ 'This is a test' | widont }}

This outputs:

This is a test

Does something special need to be done when applying widont to the output of a Redactor field?

Thanks