Firefox

Firefox

Basic Information
Release Year	2004
Product Type	Browser, Web Browser
In Production	Yes
Official Website	https://www.firefox.com/

Firefox is a free and open-source web browser developed by the Mozilla Foundation. It is officially available on Windows (10 and above^[1]), macOS and Linux.^[2]

Despite marketing itself as a security browser, by default "technical and interaction data" is sent to Firefox.^[3] You can easily disable this with an opt-out option in the GUI settings.

However, some options cannot be conveniently disabled, and requires fiddling the settings in about:config. Some of these examples include:

• Integrated Pocket technology as a built-in extension, which in its Privacy Policy uses Google Analytics.^[4]
• Google Analytics in the browser.^[5] Firefox stated they will not "give the 'data directly to Google'" but will "[collect] aggregate and non-identifiable data in numbers to ensure our development/UX changes are met well. [...] We need some data, anonymised and aggregated, to do this."

• Heavily configurable via about:config.

This is a list of all consumer protection incidents related to this product. Any incidents not mentioned here can be found in the Firefox category.

In April 2014, Mozilla released Firefox version 29, codenamed Australis. With it came the first major redesign since version 4 from 2011. The most visible difference were the rounded tabs.^[6]

With it, the ability to add custom toolbars with custom shortcut buttons was removed, reportedly due to low usage. However, this goes contrary to the promise of a customizable web browser. This change meant shortcut buttons could only be added to the same row as the URL bar, the tab bar, or the bookmark bar, taking space away from them. A separate tool bar dedicated for tool shortcuts could no longer be added.^[7]

In 2015, Mozilla introduced extension signing (add-on signing) to Firefox, meaning the browser would show a warning if the user ran an extension not approved by Mozilla. This was later expanded to block the extension, but the user was able to override it by modifying an about:config property. In 2016, Mozilla took that option away as well. This means Mozilla is able to remotely disable extensions, removing ownership from the end user.

Shortly after extension signing was announced, the user base already responded negatively, stating how this would limit the freedom of power users.^[8]

On May 3rd, 2019, a technical issue with Mozilla's add-on signing service forcibly disabled all extensions of every Firefox instance connected to the Internet (excluding older versions that predate add-on signing).

In March 2025, Firefox versions before 128 (and ESR 115) were rendered defective as a result of Mozilla no longer providing extension signing support for those versions, resulting in them losing the ability to run extensions.

^[9][10]

Starting with Firefox 57 "Quantum", released in November 2017, extensions using the XUL/XPCOM format were no longer supported, only those in the WebExtensions format.^[11]

The XUL format was the main format for Firefox extensions up to that point, allowing for a degree of customization of the web browser's appearance and behaviour that extensions in the WebExtensions format do not support, and that set Firefox apart from other web browsers like Chrome and Internet Explorer at that time, such as custom toolbars and multiple rows of tabs. The extension "TabMix Plus", then highly popular, heavily made use of this functionality.^[12][13]

According to a former Mozilla developer, the main reason for removing XUL was that giving extensions that much control over the behaviour of the web browser was a security risk.^[14]

A fork of Firefox was developed with the aim to maintain support for legacy XUL extensions, WaterFox, but it was discontinued in late 2022 and renamed to "Waterfox Classic". WaterFox versions after then do not suppport legacy extensions.^[15]

Firefox version 89, code named "Proton", brought the first major redesign since version 57 "Quantum". One of the changes were the removal of icons from the text labels in the main menu, leaving text-only labels. There was a Mozilla Connect post that the community manager recognized has "quickly received a great deal of votes" that described wanting menu icons back, or an option to enable it, given that they receive more visual clues to work and thus speed finding the needed menu item.^[16] By not implementing this suggestion, the average user has to put more effort into finding the wanted menu option.^{[citation needed - Low reliability (27 Mar 2026)][17][18]} In comparison, the mobile version of Firefox, as well as the other major web browsers (Edge, Chrome desktop, Chrome mobile) do have icons in their main menus.^{[citation needed (27 Mar 2026)]}

Main article: Mozilla introduces TOS to Firefox

On 25 February 2025 Mozilla announced in their blog that they are introducing Terms of Use to Firefox, effective 10 June 2025. ^[19] Their reasoning is to "give [the user] more transparency over [their] rights and permissions as [they] use Firefox".^[20] In the same blog post they announce an update to their Privacy Policy.

Under section "Mozilla Can Update or Terminate This Agreement" in the ToS, it is announced that updates to it will be posted online, and continued use of Firefox is taken as the user's acceptance of the new terms. No mention is made of any other commitment to notify the user (in-browser notification, etc.). In the next section, "Termination", it is explicitly stated that Mozilla will "try to notify [the user]" at their email address or next time they try to access their account, in case Mozilla denies or suspend anyone's access to Firefox.

On 10 June 2025 Mozilla has removed the "nonexclusive, royalty-free, worldwide license" in the "You Give Mozilla Certain Rights and Permissions" page of where the controversial terms of service clause used to be last seen^[21] on 15 March 2025. It is currently unknown why this change was made, as of current writing.

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