Firefox is now the last major browser protecting uBlock Origin
One browser keeps the fire burning.
Firefox logo complete with support for uBlock Origin. Image by Cybernews.
- Microsoft Edge is phasing out Manifest V2, limiting the technology that powers the full version of uBlock Origin.
- Manifest V3 restricts extension capabilities, meaning ad blockers have fewer tools to inspect and block web requests.
- Firefox is keeping full uBlock Origin support, making it the last major browser to offer the popular ad blocker without the same compromises.
- The shift gives Firefox a potential privacy advantage, as users looking for powerful ad and tracker blocking have fewer mainstream alternatives.
Key Takeaways by nexos.ai, reviewed by Cybernews staff.
Microsoft is phasing out the technology that powers the full version of uBlock Origin on Edge, leaving Firefox as the last major browser still supporting it.
The news comes hot on the heels of Microsoft's decision that its Chromium-based Edge browser will begin phasing out Manifest V2.
Chromium is Google's open-source browser project, which provides the underlying technology for browsers including Microsoft Edge, Opera, Brave, and Vivaldi.
Manifest is essentially the rulebook that determines what browser extensions are allowed to do. Version 2 gave extensions like uBlock Origin broad powers to inspect and block web requests, while Version 3 puts tighter limits on those powers.
uBlock Origin uses Version 2 permissions to inspect pages and block ads, trackers, and other unwanted content before it loads.
Where did this all begin?
Google began the broader migration from Manifest V2 to Manifest V3 in 2020, with the phase-out of V2 starting in 2024, and other Chromium-based browsers following suit.
And as uBlock Origin has been around for 12 years now, along with competitors like Adblock (17 years), end users often have a strong sense of loyalty.
Users can still use other adblockers, but the original uBlock Origin requires capabilities that Manifest V3 restricts.
So, as Chromium-based web browsers have the lion's share of browsing habits, it will take the faithful few (of Firefox) to keep the uBlock Origin fire burning.
Has your password leaked?
Firefox stands firm
Posting on Bluesky, Firefox developer Mozilla said, “Our support for uBlock Origin isn’t going anywhere.”
This means Firefox doesn't have to follow every technical decision made by Google for Chromium.
Our support for uBlock Origin isn't going anywhere.
undefined Firefox (@firefox.com) August 10, 2026 at 11:21 PM
[image or embed]
In terms of other browsers, Safari doesn't support full uBlock Origin either. Apple's browser has its own extension system, meaning uBlock Origin can't simply be installed in its full desktop form.
DuckDuckGo's browser is in a similar position, with built-in privacy and adblocking features, but that isn't the same as running the full uBlock Origin extension.
The Lite version of uBlock was designed around Manifest V3 and is more limited, so some of the original's advanced filtering capabilities are missing.
Why this matters
Overall, this is all a question of browser control and extension power. Adblocking isn't just about annoying banners – extensions can block trackers, scripts, and other unwanted requests.
A powerful content blocker can also stop tracking technologies and potentially malicious or intrusive scripts from loading.
Chromium's dominance means Google's architectural decisions have consequences far beyond Chrome itself, but Firefox's continued support gives users an alternative to the Chromium ecosystem.
And even if Firefox's user base is declining somewhat, Firefox's support for uBlock Origin could well become a genuine reason to switch browsers.
