I often find myself replying to claims that Brave, Edge, or other Chromium browsers effectively achieve the same privacy standards as Firefox + uBlock Origin (uBO).

This is simply not true.

Brave is an excellent product and what I used for a long time. But the comparison often ignores structural realities. There are important nuances that make Firefox the more future-proof platform for privacy-conscious users.

Manifest V3 permanently nerfs Chromium-based browsers #

The core issue is Manifest V3 (MV3). This is Google’s new extension architecture for Chromium (what Chrome, Brave, and Edge are built on).

Under Manifest V2, blockers like uBO used the blocking version of the webRequest API (webRequest + webRequestBlocking) to run their own code on each network request and decide whether to cancel, redirect, or modify it.

MV3 deprecates that blocking path for normal extensions and replaces it with the declarativeNetRequest (DNR) API: extensions must declare a capped set of static rules in advance, and the browser enforces those rules without running extension code per request. This preserves basic blocking but, as uBO’s developer documents, removes whole classes of filtering capabilities uBO relies on.

And Google is forcing this change by deprecating MV2.

Yeah, shitty.

Brave’s workaround for Manifest V3 #

To get around the problem, Brave is effectively swimming upstream against its own engine. It does this in two ways:

1. Native patching: It implements ad-blocking (Shields) natively in C++/Rust within the browser core to bypass extension limitations.
2. Manual extension hosting: Brave now has to manually host and update specific Manifest V2 extensions (like uBO and AdGuard) on its own servers to keep them alive as Google purges them from the store.

They wrote a great post about this too.

Brave is doing a great job, but it is operating with a sword of Damocles hanging over it. The team must manually patch a hostile underlying engine to maintain functionality that Firefox simply provides out of the box.

uBlock Origin Lite != uBlock Origin #

A lot of people also say, wait, we now have “uBlock Origin Lite” that does the same thing and is even more lightweight!

Nope.

It is “lite” for a reason. You are not getting the same blocking safeguards. uBO Lite is a stripped-down version necessitated by Google’s API restrictions.

As detailed in the uBlock Origin FAQ, the “Lite” version lacks in the following ways:

• No on-demand list updates: uBO Lite compiles filter lists into the extension package. The resulting declarative rulesets are refreshed only when the extension itself updates, so you cannot trigger an immediate filter-list or malware-list update from within the extension.
• No “Strict Blocking”: uBO Lite does not support uBlock Origin’s strict blocking modes or its per-site dynamic matrix. With full uBO on Firefox, my setup defines and exposes a custom, per-site rule set that ensures Facebook never sees my activity on other sites. uBO Lite does not let me express or maintain that kind of custom policy; I have to rely entirely on whatever blocking logic ships with the extension.
• No dynamic filtering: You lose the advanced matrix to block specific scripts or frames per site.
• Limited element picker: “Pointing and zapping” items requires specific, permission-gated steps rather than being seamless.
• No custom filters: You cannot write your own custom rules to block nearly anything, from annoying widgets to entire domains.

Firefox offers the best experience with uBlock Origin #

uBlock Origin is widely accepted as the most effective content blocker available. Its creator, gorhill, has explicitly stated that uBlock Origin works best on Firefox.

So while using a browser like Brave is better than using Chrome or other browsers that lack a comprehensive blocker, it is not equivalent to Firefox + uBlock Origin.

Brave gives you strong, mostly automatic blocking on a Chromium base that is ultimately constrained by Google’s MV3 decisions. Firefox + uBlock Origin gives you a full-featured, user-controllable blocker on an engine that is not tied to MV3, which matters if you care about long-term, maximum control over what loads and who sees your traffic.