Add no-width optional break in references

It should be possible to enter no-width optional breaks especially in the URL-field. If you have a reference (citation in a footnote) with a long URL like “See The United States Government Manual 2009/2010 (available at http://www.gpoaccess.gov/documents/all/texts/gmanual/browse-gm-09.html), 87”, the URL will not be hyphenated without no-width optional breaks. Of course one can enter them manually after having formatted the citations/bibliography, but they will be lost after a reformatting. 

Thank you for your consideration

Martin

I wish to second this request.

When footnotes are left and right justified URLs can look ugly with large extra spaces. To be able to add this special character would force the URL to break neatly in a good position so that the footnote looks as it should in a published book.