Firefox becomes the last major browser to fully support uBlock Origin

As Microsoft Edge prepares to enforce Manifest V3 and cut off Manifest V2 extensions, Mozilla has confirmed via Bluesky that Firefox will keep supporting uBlock Origin without restrictions. The distinction matters because Manifest V3 strips extensions of the APIs they need to detect and block ads effectively, degrading the core function of tools like uBlock Origin on affected browsers.

The split falls along engine lines. Edge, Chrome, Opera, Brave, Vivaldi, and Samsung Browser all sit on top of Google’s Chromium, and each inherits Google’s decision to retire Manifest V2. Firefox is one of the few holdouts running its own engine, and among non-Chromium options it stands alone here — neither Safari nor DuckDuckGo supports uBlock Origin either.

For users who rely on aggressive, no-compromise ad blocking, the practical outcome is that Firefox becomes the only mainstream browser where uBlock Origin still runs at full capability. Everywhere else, the choice narrows to the weaker uBlock Origin Lite or a browser’s built-in blocking, both of which trade away features and effectiveness.