__TOC__ = What is an add-on? = Add-ons are extensions and other additions that add new functionality to Thunderbird or change its appearance. Thunderbird has an open, extensible design and program architecture. This enables people to create "[http://addons.mozilla.org/en-US/thunderbird/ add-ons]" to Thunderbird. = Who creates add-ons? = Add-ons are mostly created by Mozilla volunteers, not Mozilla staff members (although some staffers write add-ons in their spare time). In general, though, Mozilla is generally not directly involved in the development of add-ons. Also, while Mozilla hosts a site where developers can distribute their add-ons, and while Mozilla reviews the add-ons that are distributed through that site, Mozilla is not responsible for supporting add-ons. If you need help with an add-on, you should contact the add-on's author. = Where do I get add-ons? = Most Thunderbird add-ons are distributed via the [http://addons.mozilla.org/en-US/thunderbird/ Mozilla add-ons site] (although authors can distribute their add-ons any way they choose). You can search and browse the add-ons site via a web browser. Alternatively, you can use the Thunderbird interface ({menu Tools | Add-ons}) to browse add-ons. = How do I install an add-on? = There are two ways you may install add-ons: from within Thunderbird and from outside Thunderbird. Installing add-ons downloaded from outside Thunderbird (e.g. using a web browser like Firefox): # Download the add-on to your computer, unless you already have it saved. #* A source of add-ons is Mozilla's [https://addons.mozilla.org/thunderbird/ Add-ons website]. # In Thunderbird, open {menu Tools | Add-ons}. # {for =tb31}Click the {button Install...} button at the bottom-left corner.{/for}{for tb5}Click the "gear" icon at the top-right corner to the left of the search box and then {menu Install Add-on From File...}{/for} # Browse to the location of the add-on installation file, select it, and click {button Open}. # Click {button Install Now} once the button is available. #* Add-ons that are from https://addons.mozilla.org/ are reviewed by Mozilla. #* If the author is verified, the author name will be displayed. # Restart Thunderbird to complete your changes. Installing add-ons from within Thunderbird: # Go to {menu Tools | Add-ons}. # Click {menu Get Add-ons}. # Type the name or keywords of the add-on you want in the search field and click the magnifier icon (or press {for mac}{key Return}{/for}{for win,linux}{key Enter}{/for}). # Select the desired add-on from the results list. # Click {button Add to Thunderbird...}. # Click {button Install Now} once the button is available. #* Add-ons that are from https://addons.mozilla.org/ are reviewed by Mozilla. #* If the author is verified, the author name will be displayed. # Restart Thunderbird to complete your changes. = How do I configure add-ons? = Not all add-ons have configurable options. When they do, it is up to the add-on developer to decide how users should access these options. Often developers will make an option for their add-on under Thunderbird's {menu Tools} menu. Refer to the add-on's instructions or documentation, which are probably on the page from which you downloaded the add-on. = What if my add-on is broken? = Contact the add-on developer for support. = How do I see which add-ons are installed? = To see which add-ons have already been installed in Thunderbird, select {menu Tools | Add-ons} from the menu. Installed add-ons are displayed in the {menu Extensions}, {menu Themes} and {menu Plugins} panels. = How do I update an add-on? = To see if an update is available for an add-on, select {menu Tools | Add-ons} from the menu and then check the {menu Extensions}, {menu Themes} and {menu Plugins} panels. If an update is available, it will be noted in the add-on listing. You can also force Thunderbird to check for updates. Select {menu Tools | Add-ons} from the menu. In each of the {menu Extensions}, {menu Themes} and {menu Plugins} panels, there is a {button Find Updates} button. = How do I disable or uninstall an add-on? = # In Thunderbird, open {menu Tools | Add-ons}. # Select your add-on from either the {menu Extensions}, {menu Themes} or {menu Plugins} panel. # Click {button Disable} to prevent the add-on from loading (without deleting the add-on). Alternatively, click {button Uninstall} to completely remove the add-on from your system. # Restart Thunderbird. = How do I create/develop an add-on? = You may find information on Add-on development on Mozilla Developer Network's (MDN) [https://developer.mozilla.org/en/extensions Extensions Page]. MDN has a guide on [https://developer.mozilla.org/en/creating_custom_firefox_extensions_with_the_mozilla_build_system Extensions Development].

What is an add-on?

Add-ons are extensions and other additions that add new functionality to Thunderbird or change its appearance. Thunderbird has an open, extensible design and program architecture. This enables people to create "add-ons" to Thunderbird.

Who creates add-ons?

Add-ons are mostly created by Mozilla volunteers, not Mozilla staff members (although some staffers write add-ons in their spare time). In general, though, Mozilla is generally not directly involved in the development of add-ons. Also, while Mozilla hosts a site where developers can distribute their add-ons, and while Mozilla reviews the add-ons that are distributed through that site, Mozilla is not responsible for supporting add-ons. If you need help with an add-on, you should contact the add-on's author.

Where do I get add-ons?

Most Thunderbird add-ons are distributed via the Mozilla add-ons site (although authors can distribute their add-ons any way they choose). You can search and browse the add-ons site via a web browser. Alternatively, you can use the Thunderbird interface (Tools | Add-ons) to browse add-ons.

How do I install an add-on?

There are two ways you may install add-ons: from within Thunderbird and from outside Thunderbird.

Installing add-ons downloaded from outside Thunderbird (e.g. using a web browser like Firefox):

1. Download the add-on to your computer, unless you already have it saved.
   • A source of add-ons is Mozilla's Add-ons website.
2. In Thunderbird, open Tools | Add-ons.
3. Click the Install... button at the bottom-left corner.Click the "gear" icon at the top-right corner to the left of the search box and then Install Add-on From File...
4. Browse to the location of the add-on installation file, select it, and click Open.
5. Click Install Now once the button is available.
   • Add-ons that are from https://addons.mozilla.org/ are reviewed by Mozilla.
   • If the author is verified, the author name will be displayed.
6. Restart Thunderbird to complete your changes.

Installing add-ons from within Thunderbird:

1. Go to Tools | Add-ons.
2. Click Get Add-ons.
3. Type the name or keywords of the add-on you want in the search field and click the magnifier icon (or press ReturnEnter).
4. Select the desired add-on from the results list.
5. Click Add to Thunderbird....
6. Click Install Now once the button is available.
   • Add-ons that are from https://addons.mozilla.org/ are reviewed by Mozilla.
   • If the author is verified, the author name will be displayed.
7. Restart Thunderbird to complete your changes.

How do I configure add-ons?

Not all add-ons have configurable options. When they do, it is up to the add-on developer to decide how users should access these options. Often developers will make an option for their add-on under Thunderbird's Tools menu. Refer to the add-on's instructions or documentation, which are probably on the page from which you downloaded the add-on.

What if my add-on is broken?

Contact the add-on developer for support.

How do I see which add-ons are installed?

To see which add-ons have already been installed in Thunderbird, select Tools | Add-ons from the menu. Installed add-ons are displayed in the Extensions, Themes and Plugins panels.

How do I update an add-on?

To see if an update is available for an add-on, select Tools | Add-ons from the menu and then check the Extensions, Themes and Plugins panels. If an update is available, it will be noted in the add-on listing.

You can also force Thunderbird to check for updates. Select Tools | Add-ons from the menu. In each of the Extensions, Themes and Plugins panels, there is a Find Updates button.

How do I disable or uninstall an add-on?

1. In Thunderbird, open Tools | Add-ons.
2. Select your add-on from either the Extensions, Themes or Plugins panel.
3. Click Disable to prevent the add-on from loading (without deleting the add-on). Alternatively, click Uninstall to completely remove the add-on from your system.
4. Restart Thunderbird.

How do I create/develop an add-on?

You may find information on Add-on development on Mozilla Developer Network's (MDN) Extensions Page. MDN has a guide on Extensions Development.