Well, there is a lot of panic about the change from Mv2 to Mv3, and also a lot of misinformation. It's correct that Mv3 adblocker are somewhat less effective (independent tests don't show much difference, but in change offer a way better security). Inbuild adblocker won't be affected and in other extensions not related to adblocking, it's irrelevant for the user if it is Mv2 or Mv3. Mv2 will disappear sooner or later, same as Mv1 in 2013. Some Chromium Browsers still support Mv2 extensions some time longer (Vivaldi, Opera, Brave), naturally all FF forks, probably until next year, but Mv2 is dying, yes or yes. Only problem exist for uBO, due to it's specific structure need to be practically remade from scratch to be compatible with Mv3, until now Gorhill only released uBO Lite Mv3, Meanwhile AdGuard and Adblock Plus already are in Mv3

Differences

Recent research and implementation data reveal several key advantages of Chrome's Manifest V3 (MV3) over Manifest V2 (MV2):

Security Improvements

• Enhanced extension architecture that limits access to sensitive data[^4]
• Disallows remote code execution, requiring all code to be contained within the extension[^5]
• Stricter privacy protocols that minimize data collection[^4]

Performance Benefits

• Optimized resource management through updated background processes[^4]
• More efficient performance through the new declarativeNetRequest API[^2]

Anti-Tracking Capabilities

• Recent studies show MV3 ad blockers blocked approximately 1.8 more trackers per website compared to MV2 versions[^6]
• Specific improvements in individual tools:
• Adblock Plus MV3 blocked 21.5% more trackers than its MV2 version
• Stands MV3 showed a 45.9% improvement in tracker blocking[^6]

Enhanced Combined Protection

• Using multiple MV3 ad blockers together significantly improved anti-tracking effectiveness compared to single blockers[^6]
• No reduction in ad-blocking capabilities compared to MV2, contrary to initial concerns[^6]

Sources:

[^2]: JShelter - What is Manifest v3 [^4]: Blocksi - Transition to Chrome Manifest Version 3 [^5]: Avanite - Manifest v3 and WebData Control [^6]: Privacy vs. Profit: The Impact of Google's Manifest Version 3