Always HTML

Об этом дополнении

It fixes annoying bug in Thunderbird, when composer automatically convert some HTML mails to plain text, discarding all custom formatting. For reference:
https://bugzilla.mozilla.org/show_bug.cgi?id=414299 : Format | Auto-Detect: Messages composed as HTML with <tt> for "fixed width" sections or with simple links get sent as plain text

https://getsatisfaction.com/mozilla_messaging/tags/bug_414299

Note: if You use my other extension, Stationery, You do not need to install this. Stationery already contain this bug-fix.