Add-ons
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uBlock Origin
Finally, an efficient blocker. Easy on CPU and memory. uBlock Origin (uBO) is a CPU and memory-efficient wide-spectrum content blocker that blocks ads, trackers, coin miners, popups, annoying anti-blockers, etc. in your feeds.
Ubuntu Unity unread count and quicklist
Requires Restart
Notify Unity of new mails in Thunderbird. Also, right click Thunderbird icon and get new quicklist items: Compose new mail and Contacts.
Based in awn-notif by Thesa aka Florian Birée
Un-Safelinks
Requires Restart
Replace URLs which have been rewritten by Office 365 Advanced Threat Protection with the original URL.
Ungender
Eine Thunderbird-Erweiterung, welches Binnen-Is und Ähnliches von Webseiten entfernt. Es basiert auf der bekannten Firefox Erweiterung Binnen-I be gone.
Unicodify – Text transformer
Easily and quickly autocorrect common symbols as ¼, transform text to “Unicode fonts” and change the casing.
Unified Folders Debugging
An add-on to help debugging problems with the Unified Folders mode.
Unified Search
Requires Restart
Unify the global search box and the quick filter box in a new widget (the 'Unified Search Widget') with all filter and search capabilities at once.
Unifinder Views
Requires Restart
Add more views to the unifinder (event list) in Sunbird and Lightning.
UnInbox - Quick Access
Quick Access to UnInbox in a new tab with just one click on a simple, stylish icon button on your Spaces toolbar.
Unmangle Microsoft ATP Safelinks
Users of outlook.com and o365 who have Advanced Thread Protection enabled will have all URL's in emails changed to redirect them to an Microsoft filter before opening. This is a bad idea.
This plugin will change the URL back to the original value.
UnMHT
UnMHT allows you to view MHT (MHTML) web archive format files, and save complete web pages, including text and graphics, into a single MHT file in Firefox/SeaMonkey.
Unread Count
Requires Restart
Maintains a file in the profile root directory with counts for unread messages per account. Useful for display in generic status bar, e.g.: taffybar, xmobar, dzen2, etc
Unselect Message
Requires Restart
Prevents Thunderbird from selecting the next message after you've deleted or moved the previously selected ones. Stay in control of which message you want to have selected and displayed in the preview pane; that piece of spam you're deleting...
Unsubscribe
Update Notifier
Requires Restart
Note from Mozilla: This add-on has been discontinued. Try Add-on Update Checker instead.
Notifies you when updates are available for your extensions and themes.
update-test
DO NOT install, this is for testing the update mechanism.
If you are interested in the functionality, use quicker quicksearch instead
UrgentMail
Raise X11 urgent flag if new mail is received.
This addon listens for incoming mails and causes the Thunderbird window to draw attention.
To create your own collections, you must have a Mozilla Add-ons account.
