In theory the answer is no, but in practice nobody really knows that, even Vivaldi devs. For example, Manifest V3: https://vivaldi.com/blog/manifest-v3-webrequ

In theory the answer is no, but in practice nobody really knows that, even Vivaldi devs. For example, Manifest V3: https://vivaldi.com/blog/manifest-v3-webrequest-and-ad-blockers/ https://vivaldi.com/blog/manifest-v3-webrequest-and-ad-block... > Will the Vivaldi Ad Blocker be affected by the Manifest V3 changes? I made some architectural choices early on that I believe should keep it functional, regardless of the Manifest V3 changes. Of course, there is always a possibility that the underlying Chromium architecture will change now or in the future, forcing us to do some extra work to keep this working.