User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:126.96.36.199) Gecko/20070725 Firefox/188.8.131.52 Build Identifier: Thunderbird 184.108.40.206 I receive two copies of all e-mails. Please fix. Thank you Reproducible: Always Steps to Reproduce: 1. 2. 3.
Thunderbird support forums are here: http://forums.mozillazine.org/viewforum.php?f=39 ->INCOMPLETE, feel free to reopen with a lot more information. People in the support forums may be of good help sorting it out with you.