Mozilla is a step closer to launching the future of browser extensions

Firefox
(Image credit: Shutterstock / tanuha2001)

Mozilla Firefox is to add support for Manifest v3-based web browser extensions to its online store.

Originally proposed by Google in 2018, Manifest v3 (MV3) is a software architecture revision trailed by the tech giant as one of the “most significant shifts in the extensions platform since it launched a decade ago”.

Google promised the new tech will give users “enhancements in security, privacy, and performance” and will enable them to “use more contemporary open web technologies such as service workers and promises”.

When will the change take effect?

From Monday, November 21 onwards developers will be able to upload Mv3 extensions for signing. But Mozilla is arguably somewhat late to the party; Microsoft began testing Manifest V3 in its Edge browsers as far back as October 2020.

However, not everyone is the biggest fan of Manifest V3. 

Some of the most ardent supporters of online privacy, such as the Electronic Frontier Foundation, have spoken out against the update, saying the “changes in Manifest V3 won’t stop malicious extensions but will hurt innovation, reduce extension capabilities, and harm real-world performance”.

It's unlikely that Mozilla had a great deal of choice in the decision to use MV3 within Firefox, as Google control Chromium, the open-source browser technology that powers Google Chrome and Microsoft Edge, both of which command a large browser market share

Even Apple has endorsed MV3 for its Safari browser on macOS and iOS going forward, so it may be simply a case of keeping up with the times.

Support for Manifest V2, Manifest V3’s predecessor, ends in June of 2023 for all Chromium-based browsers.

This wouldn't be the first time that Mozilla has locked horns with Google. The company has previously accused Google, Microsoft, and Apple of "self-preferencing" and nudging consumers towards using their own browsers in a September 2022 report, citing numerous examples of consumer harm.

TOPICS

Will McCurdy has been writing about technology for over five years. He has a wide range of specialities including cybersecurity, fintech, cryptocurrencies, blockchain, cloud computing, payments, artificial intelligence, retail technology, and venture capital investment. He has previously written for AltFi, FStech, Retail Systems, and National Technology News and is an experienced podcast and webinar host, as well as an avid long-form feature writer.

Read more
Woman using a Windows computer with Microsoft Edge
Don’t panic – Microsoft’s Edge browser isn’t about to subject you to a flood of unblocked adverts (not yet, anyway)
Browser
The future of mobile browsers: time for a new model?
Google Chrome dark mode
Google updates Chrome extension rules to ban affiliate link injection without user action or benefit
Google Chrome Web Store for Enterprises
Google wants to give IT admins more control over what Chrome extensions you use at work
Google Chrome with Christmas theme in Windows 11
I've used Edge, Firefox, and Opera, and yet after ten years in tech journalism, I still come back to Chrome
Woman using credit card whilst sitting at a desk with a laptop and mobile phone in view
Best web browser of 2025
Latest in Software & Services
TinEye website
I like this reverse image search service the most
A person in a wheelchair working at a computer.
Here’s a free way to find long lost relatives and friends
A white woman with long brown hair in a ponytail looks down at her computer in a distressed manner. She is holding her forehead with one hand and a credit card with the other
This people search finder covers all the bases, but it's not perfect
That's Them home page
Is That's Them worth it? My honest review
woman listening to computer
AWS vs Azure: choosing the right platform to maximize your company's investment
A person at a desktop computer working on spreadsheet tables.
Trello vs Jira: which project management solution is best for you?
Latest in News
DeepSeek
Deepseek’s new AI is smarter, faster, cheaper, and a real rival to OpenAI's models
Open AI
OpenAI unveiled image generation for 4o – here's everything you need to know about the ChatGPT upgrade
Apple WWDC 2025 announced
Apple just announced WWDC 2025 starts on June 9, and we'll all be watching the opening event
Hornet swings their weapon in mid air
Hollow Knight: Silksong gets new Steam metadata changes, convincing everyone and their mother that the game is finally releasing this year
OpenAI logo
OpenAI just launched a free ChatGPT bible that will help you master the AI chatbot and Sora
An aerial view of an Instavolt Superhub for charging electric vehicles
Forget gas stations – EV charging Superhubs are using solar power to solve the most annoying thing about electric motoring