2.0.0a2

The add-on has been rewritten as a MailExtension (#22).

• This breaks compatibility with previous Thunderbird versions.
• The add-on requires full unrestricted access to Thunderbird for being able to maintain functionality that is missing in MailExtension API.

Notable changes:

• Rmilter support has been dropped as Rmilter has been deprecated a long time ago.
• Training buttons are missing drop-down "move/copy" menus. No time to implement.
• Default and per-account training folder settings has been changed. Each folder URI textbox is replaced by an account selector and a folder path textbox.

Known major issues:

• Currently MailExtension API does not provide support for message parts on demand loading. Thus, in order to get headers the add-on has to load full mail message.
• "Unexpected error moving messages: 2147500037" and "Unexpected error copying messages: 2147500037" while moving/copying messages with training buttons. Workaround: open a folder in the destination account before moving/copying (once per session is enough).

Migration from previous versions
The add-on does not offer automated configuration migration from the XUL extension. After upgrade you should tweak the add-on configuration according to you needs.