Microsoft is beginning the retirement of Manifest V2 (MV2) extensions in Edge this month, with consumer completion targeted for the end of 2026 and managed-enterprise deprecation in early 2027.
Microsoft says that change is justified because 95% of the most-used MV2 extensions in the Edge Add-ons store have already moved to Manifest V3 (MV3). It counted 58 MV2 extensions with “meaningful usage,” only three of which lack a publicly available MV3 alternative.
Starting this month, some Edge users will see warnings in edge://extensions and on Edge Add-ons store pages. Over the following months, MV2 extensions will be disabled by default.
This shift mostly affects privacy tools that modify requests, headers, redirects, or responses. MV2 extensions will need to be redesigned or lose particular features. Extensions relying on persistent background activity must also adapt to MV3’s service worker lifecycle model.
The change affects some well-known privacy and content-blocking extensions. Among them is the classic version of uBlock Origin, one of the most popular ad blockers for Edge, with more than 13 million installs.
The change is intended to improve security and performance. MV3 replaces some long-running background code and broad request-interception behavior with more constrained, declarative mechanisms. But those constraints also remove capabilities that sophisticated privacy, content-blocking, and request-modifying extensions relied on.
Several developers have complained about the challenges of adapting to MV3. One of the main issues is the limit on the number of rules a browser extension can include.
The rules must fit within browser-defined ceilings. Chrome documents a guaranteed minimum of 30,000 static rules, a maximum of 100 declared static rulesets with 50 enabled at once, 5,000 session rules, and limits on regular-expression rules.
This does in no way mean that Microsoft is banning ad blockers. They simply need to find different ways to remain effective.
Building Browser Guard for Manifest V3
At Malwarebytes, we’ve already gone through the process of adapting our free Browser Guard extension to MV3 and came out better than we went in.
So, while Manifest V3 introduced meaningful improvements to browser security, it also created real challenges for security tools like Browser Guard.
Rather than scaling back, the Browser Guard team rebuilt its approach from the ground up, focusing on behavior, patterns, and faster response times. The result is protection that’s different under the hood, but just as committed to keeping you safe online.
You can download Browser Guard for Edge from the Edge Add-ons store.
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