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Provider for Google Calendar

Allows bidirectional access to Google Calendar

Rated 3 out of 5 stars (1,650)
198,785 users

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ExQuilla for Exchange

Thunderbird email accounts connecting to Microsoft Exchange Web Services.

Rated 4 out of 5 stars (132)
5,161 users

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DKIM Verifier Featured

Verifies the DKIM-Signature of an e-mail.

Rated 4 out of 5 stars (45)
18,790 users

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Send Later

True "Send Later" functionality to schedule the time for sending an email.

Rated 5 out of 5 stars (263)
107,865 users

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Remove Duplicate Messages

Search and remove messages which are the same as other messages in your mail folders (referred to as duplicates or dupes).

Rated 4 out of 5 stars (292)
100,004 users

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Signature Switch

Switch the signature on/off or choose a new one from your predefined set.

Rated 4 out of 5 stars (272)
55,208 users

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Lightning Calendar Tabs

Displays tabs which allows quick navigation between time periods in Lightning calendar. All views of calendar are supported. Color of tab texts can be adjusted.

Rated 4 out of 5 stars (25)
30,246 users

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QuickFolders (Tabbed Folders)

The "Swiss army knife" of folders. Turn your favorites into tabs - open folders and subfolders, move mails without scrolling around or searching. powerful + easy.

See new mail at a glance after automatic filtering - supports quickFilters addon!

Rated 5 out of 5 stars (187)
15,581 users

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Emoji

Add emojis to your e-mails.

Rated 4 out of 5 stars (64)
25,647 users

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Addressbooks Synchronizer

Synchronizes selected addressbooks with other instances of thunderbird
using local files, webdav servers or imap servers

Rated 4 out of 5 stars (79)
26,846 users

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quickFilters

Quickly generate mail filters on the fly, by dragging and dropping mails and analyzing their attributes. Create a filter in less than 10 seconds, it's as easy as: drag, click, click.

By popular demand, supports SORTING filters alphabetically.

Rated 5 out of 5 stars (70)
13,491 users

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Check and Send

Check the message contents and addresses before you send the message...

Rated 4 out of 5 stars (49)
22,420 users

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Signal Spam

Add simple functions to report spams or phishing to Signal Spam by one click.
The add-on will also alert you if you open a fraudulent e-mail (phishing).

Rated 3 out of 5 stars (164)
16,537 users

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SmartTemplates Featured

SmartTemplates offers an easy and powerful way to automatically create customized replies by auto-inserting various mail headers. Templates can be created for every mail identity, Stationery files can now be imported and used directly.

Rated 5 out of 5 stars (79)
5,523 users

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Confirm-Address

Confirm E-mail address before sending mail

Rated 4 out of 5 stars (73)
23,159 users

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Automatic Dictionary

Remembers the language you use with a person or group of people, and switches the spellchecker language automatically for you next time. You do not have to do it manually any more. It remembers and switches it for you.

Rated 5 out of 5 stars (49)
3,801 users

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AutoarchiveReloaded Featured

Automatically archives old mails (Improved version of the orginal Autoarchive Add-on)

Rated 4 out of 5 stars (25)
24,662 users

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FiltaQuilla

Adds many new mail filter actions - launch a file, suppress notification, remove star or tag, mark replied or unread, copy as "read", append text to subject.

Rated 4 out of 5 stars (100)
15,909 users

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FlexConfirmMail

Confirm mail address and attachments based on flexible rules.

(This project was renamed from "Flex Confirm Mail" to "FlexConfirmMail", due to a branding reason.)

Rated 4 out of 5 stars (11)
24,347 users

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Grammalecte [fr] (for Thunderbird)

French grammar checker. Included: conjugation tool, text formatter and spelling dictionaries.

Rated 4 out of 5 stars (16)
6,594 users

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