Message and News Reading
Decide whether to allow or block remote content in messages by comparing the names of the folders in which they are located to configured regular expressions.
ToggleReplied Requires Restart
Enables toggling of replied, forwarded, and redirected states of messages.
attachment column in search result list Requires Restart
Show the column for attachments in search results list. General search (edit-> search -> search emails) does not show by default if a message has attachments.
This addon adds this column, just as in a normal folder view.
Show a title header above messages.
Delete Read Emails Requires Restart
Adds a button in Thunderbird's toolbar that enables you to delete all your read emails at once
Reply As Original Recipient Requires Restart
Reply with the From: field set to the To: field from the original email.
Reply To All Reminder Requires Restart
Asks for confirmation when "Reply" instead of "Reply to All" is pressed on an email with multiple recipients.
Checkbox Column Requires Restart
Adds a custom column to Thunderbird's messages list (thread tree), making it easier to select multiple messages on devices with a touchscreen display.
Image Zoom (ugly fixes) Requires Restart
An ugly attempt at fixing Image Zoom
LookOut (fix version) Requires Restart
LookOut is a plugin which allows Thunderbird to interface with Microsoft's mail tools by decoding metadata and attachments encapsulated/embedded in a TNEF encoded attachment (aka winmail.dat).
Support: Thunderbird and SeaMonkey
Lowercase Email Addresses in Message Headers Requires Restart
Shows lowercase email addresses in message headers and their tooltips.
Sender Frequency Requires Restart
Adds a custom column for Sender Frequency to the thread pane
This addon returns the old view of the pop-up notifications, as in Firefox 4.0 - 43.0
Email Addresses in Message Headers Requires Restart
Shows email addresses in message headers, including those of contacts, and provides control over message header presentation.
Rspamd-spamness Requires Restart
Rspamd spam filtering system score visualization.
DisableChunks Requires Restart
The addon modifies the mail.imap.min_chunk_size_threshold preference value by setting it to 100000000.
It is a workaroud to bug 1216951
Hide Badge Icon Requires Restart
Hides the badge for new messages of the Thunderbird app icon on Mac OSX.
ThunderBird Ticker Requires Restart
Extension for creating support tickets based on mail.
SecondOpinion Requires Restart
This extension implements a convenient way to check and upload attachments against VirusTotal.com
Synchronize your favorite RSS sources with Thundebird and Feedly