Hi there; I will do what I can with my basic English to explain what's wrong, but I'm posting here because French forum didn't help, nor Bugzilla.

So;

1. Everything was working fine before build #31, the problems started then and has never been solved since. 2. I have several accounts in Thunderbird and Some of my accounts are subscribed to some mailing lists 3. Since V31, When I reply to males from one of these lists, the reply's sender is different from The account the mail was sent to, and I have to change the sender back manually for each reply; This doesn't happen with other mails I receive; I know it sounds crazy, at least for me, but can you help, Thanks.