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Theme Font & Size Changer (fixed)
Fixed version (no 90 day timer till silent failure) of the popular "Theme Font & Size Changer for Thunderbird" addon
Theme Font & Size Changer for ThunderBird
Theme Font & Size Changer lets you change the global font size and font family used for the user interface in Firefox. Design your browser with your favorite font.
TheRealURL Requires Restart
Get URL information: expand short URLs, get title and content type information without visiting the site.
UPDATE, AUG 2013: THIS EXTENSION IS NO LONGER SUPPORTED. The source is open - if you wish to take on the development, you're welcome.
Thin Tabs
Extremely thin tabs optimized for the squared variants of Classic Theme Restorer.
Please see description for updates!
Thread in same folder
Runs after junk classification and filtering to make sure a newly-received message lands in the same folder as its parent in a thread.
ThreadBubble Requires Restart
Make Thunderbird resort threads by date when a new message arrives. *** This add-on is no longer required for new versions of Thunderbird! ***
ThreadKey
Strike the 'T' key to sort messages by thread, strike the 'U' key to sort them unthreaded again, just like the 'G' key switches to Grouped By Sort view.
ThreadVis
Displays a small graphic visualising the context (thread) of the currently selected email.
THUNDER!Box Requires Restart
Thunder!Box allows transferring contacts from your Thunderbird-Addressbook to the phonebook of a connected AVM FRITZ!Box FON router and back. You may also use your addressbook to initiate calls.
ThunderAI
ThunderAI uses the capabilities of ChatGPT to enhance email management.
It enables users to analyze, write, correct, and optimize their emails.
There is no need for an API key and is possibile to use this extension even with a free account!
Thunderbird Addons Test Requires Restart
This addon is completely defunct and merely for internal testing purposes. Don't expect it to do anything.
Thunderbird Are Go Requires Restart
This plays audio to boost emotion when Mozilla Thunderbird start up.
Mozilla Thunderbird Are Go!
Thunderbird Biff Requires Restart
This add-on provides a visual indicator of new Thunderbird mail availability in supported clients (Firefox, Sunbird) and Thunderbird itself. Note: you MUST install this add-on in BOTH Thunderbird and supported clients as there are both client AND ser...
Thunderbird Chat Notification Requires Restart
Chat notification for Mozilla Thunderbird. Notification with alert (click on alert open conversation) and sound.
Thunderbird Conversations Featured
This addon provides a conversation view for Thunderbird, grouping messages together and allowing you to reply "inline" thus providing a more efficient workflow.
Thunderbird Email 2 CSV Exporter
This add-on has been thoroughly tested on all platforms up to Thunderbird version 115. It allows you to target specific file folders and tag them for export, generating a CSV-formatted export file. Great for a large number of emails and Mailchimp.
Thunderbird Message Filter Import/Export Requires Restart
Thunderbird Message Filter Import/Export is a thunderbird/mozilla extension to import/export message filters.
To create your own collections, you must have a Mozilla Add-ons account.