Add-ons
Extensions by Name
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Show Password On Input
Requires Restart
Gives an option to show the master password on input
ShowContactFoto
Displays the contact photo/image/picture of the sender/recipients while reading/composing message.
Images are taken from local image files or Address Book (see addon's options page).
ShowFolderSize-T
Requires Restart
Shows folders size on disk.
This add-on is a fork of ShowFolderSIze.
https://freeshell.de//~kaosmos/index-en.html#foldersize
Shrunked Image Resizer
Make your photos smaller, so they don't take forever to email.
*Shrunked Image Resizer is no longer maintained.*
Sieve
This Extension implements the ManageSieve protocol for securely managing Sieve Script on a remote IMAP server...
Sieve Out of Office New
Requires Restart
A Thunderbird plugin to allow one to set out of office messages and / or redirect emails to colleagues via a easy to use pop-up dialog.
This Out of Office plugin requires that your POP3 / IMAP server also have a sieve service.
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).
Signature /Auto Paste /Prefill Fourms
Requires Restart
Makes everyday entries to forms & forums simpler!
Add a sig. with just a Rclick of the mouse and select 'Add Sig.' from the context menu.
(Please, note: What you see in the pic is only an example. ThoseRMine Sorry, you have to make your own tabs. )
Signature Fixer
Signature Switch
Switch the signature on/off or choose a new one from your predefined set.
Signature sync for Gmail
This extension allows you to automatically use your signature from Gmail accounts in Thunderbird. No longer need to maintain two separated signatures!
Silent Block
Simple HT Jumper
Requires Restart
A temporal simple jumper of HTML and Plan TEXT view mode on showing messages and replying messages for Thunderbird without changing the default setting.
Simple Locale Switcher
Requires Restart
An easier management of the user interface language
Simple Mail Redirection
Allows you to resend (also known as redirect) email messages.
Uses 'cardbook' if installed
Bases on the add-on 'Mail Redirect' by Onno Ekker and Pawel Krzesniak
Please see the support page on how to use and why it sometimes does not work!
Simple Search-For Extension
Requires Restart
Adds a "Search for" item to Thunderbird's context menu, like in Firefox.
Simple Startup Minimizer
This extension will minimize Thunderbird on startup, it is very simple and I didn't put much work into it but it should work on all platforms. Please let me know if you want more features added into it.
Simple Steganography
Requires Restart
Hide messages in PNG-32 images, extract them via context menu. The text is embedded invisibly by a "Least Significant Bit" algorithm.
You can also encode very short messages by re-sorting text lists and extract them via context menu.
To create your own collections, you must have a Mozilla Add-ons account.
