My favourite thunderbird extensions

• Display Quota - Display IMAP quota.
• Unselect Message - Don't select next message after move/delete. Click outside list to select no message.
• Folderpane Tools - Reorder accounts. Choose startup folder.
• GMailUI - Search "from:John subject:Hello", ...
• Nostalgy - Save message (i.e. move/archive) with a single key press. Go to folder with a single key press. Quite configurable.
• Disable DragAndDrop - Disable drag and drop in the folder pane.
• Maximize Message Pane - Hide/show folders. Maximize/unmaximize message pane.
• Mozilla New Mail Icon (Biff) - In system tray

To check all IMAP folders for new messages (no need to click on a folder to see if there's unread messages there):
Edit -> Preferences -> Advanced -> General -> Config Editor: mail.check_all_imap_folders_for_new = true

Display IMAP quota:
Edit -> Preferences -> Advanced -> General -> Config Editor: mail.quota.mainwindow_threshold.show = 0

Disable "flowed" formatting:
Edit -> Preferences -> Advanced -> General -> Config Editor: mailnews.send_plaintext_flowed = false

See also: My favourite firefox extensions

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