Chris,
Downloaded latest 12.0 beta release and IMAP appears to work again;
however no Calendar. So downloaded the 1.4b2 of Lightening.
Thunderbird reports Lightning is working but the Calendar tab is not
showing and the option to display the Calendar on the View menu is
grayed out as well as the To Do List option.
This is a major bug (IMAP issue) and Mozilla should have released TB
11.1 with the fix, instead of making everybody try and sort this mess
out. I use Thunderbird at work instead of Outlook, so this really caused
problems.
As this type of issue is going to happen again with the fast release
schedule, Mozilla should incorporate an option of allowing the user to
revert back to a previous working version. May be the install should
give the option of saving the current version in another folder so that
it can be re-installed. Or may be Mozibackup(?) could be modified to do
this for the install only.