It’s been a long time coming, but Google will finally close a loophole in its popular Chrome browser that enabled ad-blocking tools. Moreover, the change will have cascading effects on other web browsers, many of which use the underlying, open-source Chromium that powers Google’s Chrome.
The core issue stems from changes to how extensions communicate with browsers, such as what permissions they need and features they will use. This information is part of what’s called a manifest, and Google began the process of transitioning from Manifest V2 to Manifest V3 (MV2 and MV3) several years ago. The company pitched MV3 as an important upgrade that would improve security and performance for extensions. However, MV3 also replaced features from MV2 that enabled ad-blocking extensions, and the new MV3 version was widely considered less effective for ad-blocking.
After years of delays, Google finally made the jump to MV3 and even started auto-disabling MV2 extensions for Chrome users in 2024. But all the while, users could get around MV3 and continue using MV2 extensions by toggling hidden settings in Chrome called ‘flags.’ Now, Google is removing those flags.
Here’s what that means for users. First, if you were still using an MV2 extension via a bypass of some sort, that will eventually stop working. It’s not entirely clear when, but based on posts from a Chromium contributor spotted by Neowin, it looks like Chromium version 151 will get rid of several flags that allowed people to continue using MV2 extensions.
Moreover, this will have an impact on the many other web browsers that are also built on Chromium. Neowin notes that Microsoft’s Edge browser will likely follow suit. The publication initially said Opera would also phase out MV2 based on emails the company sent to developers, but later added an update noting that Opera still plans to support MV2 but is also slowly phasing out the older manifest. Likely other Chromium-based browsers will follow suit.
So, where does that leave users who want to run an ad-blocker? The easy option is to switch to one that complies with MV3, but generally, those aren’t as effective as their MV2 counterparts. (I’ve tried both MV2 uBlock Origin and the MV3-compliant uBlock Origin Lite and found both worked well enough, but the MV2 variant does offer many more features and customizability.)
If switching to MV3 extensions isn’t appealing, users can also switch browsers entirely. Firefox, for example, has committed to supporting MV2 extensions. Several Chromium-based browsers, like Brave, Vivaldi, and Opera, also now offer built-in ad-blocking capabilities that shouldn’t be impacted by the MV3 changes.
It will be particularly interesting to see what happens next for ad-blockers. Google Chrome continues to hold about 70 per cent of global browser market share, or about 52 per cent of Canadian browser market share, roughly unchanged since 2024. The MV3 change doesn’t appear to have caused a mass exodus to other browsers yet, and I’m not sure closing the final MV2 loophole will change much for Google.
Via: Neowin, 9to5Google
