Mozilla Firefox and Brave Keep uBlock Origin Alive as Edge Drops Support

Microsoft Edge is preparing to drop support for Manifest V2 extensions, a move that will effectively kill uBlock Origin on the browser. For many Windows 11 users, this removes the most effective ad-blocking solution from their primary web browser. However, the landscape isn’t as bleak as it might seem, thanks to strong commitments from Mozilla Firefox and Brave.

According to recent announcements from Mozilla and Brave, both browsers will continue to support uBlock Origin and other Manifest V2 extensions. This ensures that users who rely on advanced ad-blocking features have reliable alternatives that won’t disappear when Edge makes the switch.

Why Edge Is Dropping uBlock Origin

The root cause of this shift is the industry-wide transition from Manifest V2 (MV2) to Manifest V3 (MV3). Google, which developed the Chromium engine used by Edge, Chrome, and Brave, has been pushing for MV3 for some time. The new framework is designed to be more secure and performant, but it introduces significant restrictions for extension developers.

Specifically, MV3 removes support for the WebRequest API. This API is what allows ad blockers like uBlock Origin to dynamically intercept and block network requests before they load. Without it, extensions cannot filter content in the same way. While MV3 extensions can still block ads, they rely on static blocklists rather than dynamic interception, which is less effective against modern, complex ad networks.

Microsoft Edge has confirmed that it will follow Google’s timeline for deprecating MV2. This means uBlock Origin will stop functioning in Edge well before the final cutoff date, leaving users to find alternatives sooner than expected.

Firefox and Brave Stand Firm

In response to the news, Mozilla took to X to reassure users: “Firefox support for uBlock Origin is not going anywhere.” Firefox uses the Quantum engine, which is separate from Chromium. This architectural independence allows Mozilla to maintain support for MV2 extensions even as the rest of the industry moves on.

Brave has also committed to keeping uBlock Origin alive. The browser maker emphasized that it hosts MV2 extensions on its own servers, ensuring availability even if the Chromium standard fully abandons them. To enable these extensions in Brave, users need to navigate to Settings > Extensions > Manifest v2 extensions.

It is worth noting that Brave also includes a built-in ad blocker that is unaffected by the MV2 changes. This provides a baseline level of protection for users who prefer not to manage third-party extensions.

uBlock Origin Lite vs. Full uBlock Origin

For users forced to switch to Chrome or Edge, the only remaining option is uBlock Origin Lite. This extension is built for MV3 and does not require the WebRequest API. However, the limitations are real.

uBlock Origin Lite cannot dynamically intercept requests. Instead, it relies on pre-defined filters. While it blocks a significant number of ads, it struggles with:

Ads that load via JavaScript or iframes
Complex ad networks that change their structure frequently
Performance optimization for heavy ad pages

In practical terms, this means you might still see ads load, and your browser may not perform as smoothly on ad-heavy sites compared to the full version of uBlock Origin.

What This Means for You

If you are currently using Edge and rely on uBlock Origin, you have a few choices. You can switch to Firefox or Brave to keep the full ad-blocking experience. Alternatively, you can stay on Edge and accept the limitations of uBlock Origin Lite, or explore other MV3-compatible ad blockers.

For now, the choice of browser matters more than ever for privacy and ad blocking. Firefox and Brave are proving that they can maintain compatibility with powerful tools even as the industry standard shifts.

Source: Latest from Windows Central

Over to you: Are you switching to Firefox or Brave to keep using uBlock Origin, or will you stick with Edge and try uBlock Origin Lite?