Appearance and Customization
AddressBook in Tab Requires Restart
Adds a button that can be put in toolbars which opens the addressbook in a new tab like pastismans AddressBookTab
Keep in Taskbar Requires Restart
A simple plugin that makes the Close button behave exactly like the Minimize one.
lightningWeather Requires Restart
LightningWeather shows the weather forecast in the background of the calendar so you can easily coordinate your activities with the weather.
CustomizeMyBird add-on offers ui tweaks to improve Thunderbirds appearance (squared tabs, custom tab height, alternative Add-on Manager appearance, compact main toolbars and more).
Checkbox Column Requires Restart
Adds a custom column to Thunderbird's messages list (thread tree), making it easier to select multiple messages on devices with a touchscreen display.
Layout Button Requires Restart
A toolbar button to switch between layouts.
Large Fonts Requires Restart
This add-on enables you to change the font size of the plain text editor of Thunderbird.
Tategaki Requires Restart
Tategaki allows vertical writing-mode on mail compose window.
Highlight Unread Folders Requires Restart
This add-on enables highlighting the account names which contain unread messages.
Send Later Button Requires Restart
A simple button to invoke the (already existing) send later functions.
ansitel Click-to-Dial Thunderbird Requires Restart
Click-to-Dial Plugin für ansitel VoIP-Telefonanlagen zum Markieren und Wählen von Rufnummern in Mozilla Thunderbird.
Lowercase Email Addresses in Message Headers Requires Restart
Shows lowercase email addresses in message headers and their tooltips.
The "Responsible Blocker" arrives to save the Internet, this extension blocks all those annoying ads, but allows only small and acceptable ads, so the websites you like can continue online.
The "Responsible Blocker" arrives to save the Internet
Sender Frequency Requires Restart
Adds a custom column for Sender Frequency to the thread pane
This addon returns the old view of the pop-up notifications, as in Firefox 4.0 - 43.0
Add-on for Firefox and Thunderbird. Replaces built-in notifications with the OS native notifications. It supports most Linux Desktop Environments, Windows 8.1 & 10.
Email Addresses in Message Headers Requires Restart
Shows email addresses in message headers, including those of contacts, and provides control over message header presentation.
Stylish-Custom Requires Restart
custom additions to Stylish extension