Folders and Filters
Automatically marks all messages in junk folders as read.
folderplus Requires Restart
This extension adds some basic missing features about folders.
Move mails to their conversation folder. Navigate to folder with new keyboard shortcuts.
Collapsed Unread Requires Restart
Shows unread email count for collapsed folders even if the unread mails are in subfolders.
Toggle Folderpane View Requires Restart
This addon provides a toolbar button for toggling between the "All" and "Favorite" views in the folderpane.
Folder Levels Requires Restart
Rank your email folders by how much you care about them, and hide the ones you don't need right now.
SavedSearchThemAll Requires Restart
A Thunderbird extension to automagically extend all the saved searches to all the foders!
TotalQuickFilter Requires Restart
Reboot the QuickFilter bar.
Sieve Out of Office New Requires Restart
A Thunderbird plugin to allow one to set out of office messages and / or redirect emails to colleagues via a easy to use pop-up dialog.
This Out of Office plugin requires that your POP3 / IMAP server also have a sieve service.
IMAP Draft Unread Requires Restart
This is a Thunderbird addon that lets you customize the behavior of the IMAP draft unread messages. No more new mail notifications for your drafts!!
Tidybird Requires Restart
Organize email into folders quickly and easily.
SavedSearchInSubFolders Requires Restart
This addon allows virtual folders (saved searches) to automatically process all subfolders of their selected target folders.
The search targets are updated automatically whenever a new folder is added, or a virtual folder is updated.
Synchronize your favorite RSS sources with Thundebird and Feedly
Automatically marks all messages in the [Gmail] folder and all subfolders as read.
SmartFilters Requires Restart
Tired of writing a lot of filters? Install SmartFilters now to organise your mailbox automatically. It can sort out your mailing lists and robot emails.
QuickFilter Watched Threads Requires Restart
Adds a filter to show only watched threads
Adds personal filters to quickfilter toolbar
This addon extends filtering to read messages downloaded during an IMAP synchronization (bug 308148)
This addon adds an entry in the right-click menu which re-threads selected messages together (groups selected messages into the same thread)". This is done by _modifying_ messages; the author of the addon declines any responsibility for data loss.
CapsKiller Requires Restart
Caps Killer is a protection against newbies using caps in their mails.