User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:188.8.131.52) Gecko/2008071615 Fedora/3.0.1-1.fc9 Firefox/3.0.1 Build Identifier: Since Thunderbird can handle more than one account, it is not desirable that "Plain Text Messages" is the same for all accounts. It would make more sense to have per account. I therefore propose it is moved to Edit->"Account Settings"->"Composition & Addressing". See mock up. Reproducible: Always
Again, why? I can't envision someone really needing/remotely wanting that. Typically you just want to set things once (if at all) and be done with it IMO.
You are right. This really should stay in Preferences. I'm closing as WONTFIX.