Add-ons
Message Composition
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Clippings for Thunderbird
Save frequently-entered text for pasting later.
Owl for Exchange
Allows you to use your Exchange and Office365 email account with Thunderbird using Outlook Web Access (OWA).
ThunderAI Sparks
ThunderAI Sparks is an add-on designed to add advanced features to ThunderAI.
ThunderAI (ChatGPT, Gemini, Ollama in your emails)
ThunderAI uses the capabilities of ChatGPT, Google Gemini or Ollama to enhance email management.
It enables users to analyse, write, correct, assign tags, create calendar events and optimize their emails.
Attach from Clipboard
Create file attachments directly from the system clipboard.
StandardTexter
With the help of this Add-on, up to 99 pre-made texts (standard texts, text modules or even signatures) can be stored, which can then be retrieved and inserted when writing an e-mail.
The texts can be preformatted with HTML.
Emoji
It permits just with a single click to copy an emoji.
There is a search-box and the "Most used emojis" section (the first one).
If you want to send feedback or report bug, please contact me
Antidote connector for Thunderbird
Integrate Antidote with Thunderbird to proofread your emails, check your spelling and grammar, and consult the dictionaries and language guides. Get alerted to abrasive tone and missing attachments before sending a message.
Signature Switch
Switch the signature on/off or choose a new one from your predefined set.
Webbuttons - Skype Web
Adds a button in the toolbar for Skype Web. Icon source: https://www.flaticon.com/free-icon/skype_16167326
Webbuttons - Google Messages Web
Adds a button in the toolbar for Google Messages Web. Icon source: https://www.flaticon.com/free-icon/comment_9449200
Send Later
True "Send Later" functionality to schedule the time for sending an email.
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.
Grammar, Proofreading & Spell Checker
Check the grammar and spelling directly inside Thunderbird using Wordeep technology
HTML Source Editor
Allows to edit the source of the currently composed message. A simple alternative to ThunderHTMLedit.
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.)
ReFwdFormatter
Remove the ">" prefix from quote when you make a reply.
[Source code] https://github.com/isshiki/ReFwdFormatter
OpenAI Proofreader
This extension uses OpenAI gpt-4o-mini to proofread emails when the user clicks the extension icon.
Usage requires an OpenAI API key. OpenAI does not offer a free usage tier. Proofreading a 4-5 paragraph email costs a fraction of a cent.
Gemini Proofreader
This extension uses Gemini Flash 2.0 to proofread emails when the user clicks the extension icon.
Usage requires a Gemini API key. There is a free usage tier that should be more than adequate for almost every user.
DS-BCC
Data protection extension, to avoid data mishaps with circular mails:
1. warning for e-mail with multiple recipients not in BCC (exceptions possible)
2. warning for roundmails with a different recipient domain
3. warning if PGP key is present
To create your own collections, you must have a Mozilla Add-ons account.
