Known as "Manifest V3" these are changes that have been announced in October 2018 by Google for the Chromium open-source browser engine, namely to the WebExtensions API.
The changes update how browser extensions interact with Chromium-based browsers, such as Chrome, Brave, Opera, Vivaldi, and, as of this year, Microsoft Edge.
At the time the changes were announced in 2018, Google said the main intent was to improve extension security, make extensions more performant, and give users greater control over what extensions do and with which sites they interact.
The announcement caused a huge backlash from both users, extension developers, and even other browser makers. Users, in particular, viewed the move as a dirty hit from Google —an advertising company— to sabotage the ad-blocking ecosystem.
Browsers like Opera, Brave, and Vivaldi were quick to distance themselves from the debacle and announced plans to ignore the Manifest V3 updates and allow users to keep using ad blockers.
Mozilla, which also implemented the WebExtensions API inside Firefox for compatibility reasons, also denounced Chrome's plans and said it would not be following Google's WebExtensions API update to the letter and that it would make some changes of its own to allow ad blockers to continue to work as intended.
Since then, the Manifest V3 changes have started rolling out in Chrome, with some of the grumbling having died down, although some ad blocker extension devs seem to have given up on their products' ability to reliable block ads once these changes reach stable versions of Chrome.
These changes have now also reached Microsoft's new Chromium-based Edge, where they are already live in beta and stable releases.
However, Microsoft said today that these changes wouldn't cripple ad blockers, a fear that many users had.
"We recognize the value of content blocking extensions and appreciate the role they play in honoring user's choice by blocking advertisements and enhancing privacy by blocking cookies and we want developers to continue to offer these capabilities," the Microsoft Edge Team said today.
"After an extensive review of the concerns raised by content blockers and the community, we believe that a majority of those concerns have been resolved or will be resolved before Web Request API is deprecated."
**The Web Request API is a function used by ad blockers that will be removed with Manifest V3.