Software modules to extend Firefox web browsers
Add-on
is the
Mozilla
term for
software
modules that can be added to the
Firefox
web browser
and related
applications
. Mozilla hosts them on its official add-on
website
.
[1]
Browser extensions
are the primary type of add-on. In 2017, Mozilla enacted major changes to the
application programming interface
(API) for extensions in Firefox, replacing the long-standing
XUL
and
XPCOM
APIs with the
WebExtensions API
that is modeled after
Google Chrome
's API.
[2]
[3]
[4]
Thus add-ons that remain compatible with Firefox are now largely compatible with Chrome as well.
[5]
As of January, 2024, there are more than 36,000 add-ons and over 495,000 themes available for Firefox.
[6]
[7]
Current add-ons
[
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]
Extensions
[
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]
WebExtensions
[
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]
Starting with Firefox 57, only the new
WebExtensions API
is supported.
[3]
[8]
Themes
[
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]
Early versions of Firefox supported
themes
that could greatly change the appearance of the browser, but this was scaled back over time. Current themes are limited to changing the background and text color of toolbars.
[9]
(These lightweight themes were formerly called personas.
[10]
)
Historical add-ons
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Extensions
[
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]
Legacy extensions
[
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]
Prior to 2017,
Firefox
supported
extensions
developed with different APIs:
XUL
,
XPCOM
, and
Jetpack
.
[11]
Mozilla
now refers to these as legacy extensions.
[4]
Plug-ins
[
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]
Plug-ins
are no longer supported in Firefox. In the past, they were used to handle
media types
for which the application did not have built-in capability. They were
deprecated
due to security concerns and improvements in
Web APIs
.
[12]
The last one that was officially supported was
Adobe Flash Player
, which Adobe discontinued in 2020.
[13]
[14]
Restrictions
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]
Mozilla
had no mechanism to restrict the privileges of legacy
Firefox
extensions. This meant that a legacy extension could read or modify the data used by another extension or any file accessible to the user running Mozilla applications.
[15]
But the current WebExtensions API imposes many restrictions.
[16]
Starting with Firefox 40, Mozilla began to roll out a requirement for extension signing.
[17]
It is now required in all official Firefox releases.
[18]
Website
[
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]
Add-ons for Firefox
|
Type of site
| Hosts add-ons
|
---|
Owner
| Mozilla Foundation
|
---|
URL
| addons
.mozilla
.org
|
---|
Commercial
| No
|
---|
Registration
| Free; only needed for developers or for special features
|
---|
Current status
| Active
|
---|
The
Mozilla
add-ons website is the official repository for
Firefox
add-ons.
[1]
In contrast to
mozdev.org
which provides free hosting for Mozilla-related projects, the add-ons site is tailored for
users
. By default, Firefox automatically checks the site for updates to installed add-ons.
[19]
In January 2008, Mozilla announced that the site had accumulated a total of 600 million add-on downloads and that over 100 million installed add-ons automatically check the site for updates every day.
[20]
In July 2012, the total had increased to 3 billion downloads from the site.
[21]
References
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]
External links
[
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]
|
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Projects
|
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Mozilla
Labs
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Mozilla
Research
| |
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Mozilla
Foundation
|
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Forks
| |
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Discontinued projects are in
italics
. Some projects abandoned by Mozilla that are still maintained by third parties are in
underline
.
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Organization
|
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Foundation
| |
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Subsidiaries
| |
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Official affiliates
| |
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People
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