I do basic email, pop with Comcast (US Cable provider). therefore, I don't have half that complexity. Some of your extensions seem to seriously nitpick tweak some features of thunderbird, talk about specific.
But, there are 2 necessaries.
MinimizeToTray
Obvious, so that minimized it will get out of the way. New mail notifications of course still appear in the tray.
ContactsSidebar
Puts the contact list underneath the folder list for quick access sending emails.
Other:
mboxImport
Allows you to import .mbox file, which is the only way I could get files off of TheBat! and onto Thunderbird when i switched.
MozBackup
*not extension* However, it works with Firefox and Thunderbird and installs seperately, allowing you to create a backup... easily.
Well, since we had one for Firefox, I thought I'd start one for Thunderbird. I'm moving from OSX Mail to Thunderbird and have a few extensions that given me basically all the same functionality Mail has:
QuickQuote
This allows you to highlight a piece of a message and have that be the only thing highlighted in the reply
Enigmail
OpenPGP encryption for Thunderbird. (GnuPGP installed separately)
Correct Identity
This allows you to pick from a drop down box in a new message (or reply) to select from which identity you should send an email
SyncOnArrival
Allows you to have multiple IMAP folders sync whenever email arrives in them. If you don't use IMAP this probably won't be a big deal for you, but for me (who also has server based mail rules), it's a life saver.
ConfigDate
Allows you to change the configuration of the date display in the message list pane
And just a couple I like:
AllowTemporaryHTML
Just what it says. Allows you to show HTML mail for just certain messages. Good for us email purist who think HTML email is the antichrist. ![]()
DisplayQuota
Displays your mail quota in the status bar.
SortExtensions
Sorts the list of installed extensions. Because I am that anal retentive. ![]()

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