Hello,I have found the Thunderbirdbiff add-on for both Firefox and Thunderbird, that is not listed as free-soft add-on on gnu.org. The add-on is released under the MPL 1.1.
Link to the project homepage: http://thunderbirdbiff.mozdev.org/Here they state everything on that page is under MPL 1.1: http://www.mozdev.org/copyright.html
Have a nice day! -- http://gnuzilla.gnu.org
