Google Chrome Adblock changes explained: uBlock Lite & Manifest V3

Joel Loynds
man screaming as ublock, firefox and chrome logos, as well as the text manifest v3, float around him

As browsers begin to update to Manifest V3, ad blockers are in the process of updating. However, some developers aren’t confident that you’ll get the same performance. 

We break down everything you need to know, including which ad blockers work with Manifest V3 browsers.

We’ll also discuss the difference between what Mozilla is doing with Firefox, and why you should consider switching from Chrome.

What is Manifest V3?

man looking confused at pc

Manifest V3 is an updated version of the Chrome extension manifest file format. It contains the application programming interface (API) that allows browsers to work with extensions. Every browser will be implementing it, including Chrome, Firefox, and Opera.

Are all Chromium browsers getting Manifest V3?

squidward in the spongebob episode sb-192 looking at the spongebob clones with different browser logos on their faces

It’ll also come to any Chromium-based browser or Firefox fork, as the aim is to build a standard across every browser.

Browsers running Chromium including Brave, Arc, Edge, Opera, and Opera GX, will all be moving to Manifest V3. Waterfox and other forks of Firefox will also be moving to V3. 

Will Manifest V3 break ad blockers?

No, ad blockers have already been updated to support Manifest V3. However, it’s hotly contested that the V3 update will restrict some of the functionality of ad blockers.

A major drawback is the removal of “Web Request”. This feature allows ad blockers to block incoming domains, meaning that it can catch ads before they even load.

However, Web Request can be used maliciously, like acquiring user data. The move to Manifest V3 removes this element, forcing developers of ad blockers to work around the new system.

Without access to monitoring traffic, the new “Declarative Net Request” only allows developers to add a pre-made list of rules. Even more restrictive is the number of rules has been shrunk to 30,000. 

uBlock Origin needs 300,000 to function properly, hence why the Manifest V3 version is now dubbed “Lite”. 

uBlock Origin Lite vs uBlock Origin

ublock origin logos

Since the move to Manifest V3, the uBlock Origin developer has had to create uBlock Origin Lite. It runs very similar to Origin at its default settings but isn’t intended to be a replacement.

Breaking it down, here are the main differences between uBlock Origin and Lite:

  • Filter lists can only be updated with the extension
    • This means you can’t make your own filters or import external lists
  • No blocking of remote fonts and scripting
  • No dynamic filtering
  • No blocking of large on-page elements
  • No header filter options
  • No strictly blocked pages
  • No per-site switches

Part of this information came from Reddit and the FAQ.

uBlock Origin is the best ad blocker around. Its extensive filtering options and strict rules it uses make it an excellent option.

As of right now, uBlock Origin does work on Chrome as the developer has a workaround. Come 2025, it could be that Chrome and Chromium browsers might only have access to the Lite version.

However, Firefox will continue to use V2, which the developer of uBlock has already said will be updated as normal.

As of right now, these ad blockers are ready to support Manifest V3 browsers, like Chrome and Firefox:

This isn’t a definitive list, as many ad blockers are out there. We’ll be sure to update the list once we have more information.

Firefox to support older Manifest V2 alongside V3

firefox logo next to text saying manifest v2 and v3

Mozilla, the non-profit organization behind Firefox, announced last year how it’ll handle Manifest V3. While it has already implemented the update, it kept key parts of Manifest V2 that ad blockers relied on. 

However, there is a security flaw in doing so. Issues with malicious extensions have plagued the software for years.

Mozilla has admitted this, it finds it key to ensure compatibility across the board.

For now, it seems that ad blockers will work just as intended on Firefox and any forks that follow.

Does Google Chrome support ad blockers?

chrome logo

Yes, Google still allows ad blocker extensions on Chrome. However, now they’re having to run via Manifest V3, resulting in critical components having to be removed.

The average user might not even notice the difference. Some developers have stated that there’s no discernible difference between the versions. 

Others have written lengthy arguments about why the move is bad for the user. This includes breaking key components of ad blockers. 

Manifest V2 is set to be retired entirely by June 2025. Right now, some extensions – like uBlock Origin – are using a workaround. 

Manifest V3 became the default in Chrome in June 2024, with version 127.

Will Manifest V3 break Brave Shields and built-in ad blockers?

brave logo

No, as these aren’t reliant on the Manifest files and are built into the software itself, it circumvents any of the changes. Browsers like Brave will still function as expected.

Safari and Manifest V3

As Safari only works on macOS as of 2010, the ad-blocking situation is a little different. Safari is on Manifest V3 and has been for far longer than Google Chrome. 

Ad blockers on Safari act as a separate program, as well as an extension. In our testing, it seems like AdBlock for Safari wasn’t working for YouTube, but fine elsewhere. We had similar results with AdGuard and AdBlock Plus.

safari logo

It seems that Google’s new method of getting ads onto YouTube is working as planned. Some users have experienced ad injection into the video, leaving some with a 30-second-long black screen.

Others have experienced the reduced capabilities of ad blockers with Manifest V3. Blockers like AdBlock Plus are allowing ads through on browsers like Chrome and Safari.

Should you switch browsers from Chrome?

firefox logo with question mark

While we fully recommend Firefox, the wider browser scape is all running Chrome’s engine, Chromium. 

The other issue is that Firefox isn’t fully compatible with parts of the web. Some web apps require Chromium to run, leaving you potentially needing a Chrome-based browser at some point.

However, we do recommend Brave and Arc Browser, but you’ll need to get adjusted to its layout.

Arc is also planning on building its own ad blocker similar to how Brave has implemented Sheid.