Brave have said they’ll retain support for Manifest v2, but realistically that’s likely to be non-trivial amounts of work, and get harder as their upstream codebase moves away from it and the internals get switched over from the old webRequest mechanism.

They’ll have to patch things manually to keep it working, which is likely to get harder and harder. If Google want to make it hard for them to retain support, they can do so.

At some point they may not have the resources to keep doing that and might have to decide between forking the codebase and losing manifest v2. If they fork then they’ll have a load more work to do in backporting security changes etc.

They’ll also have to find a way to retain the old manifest v2 versions of extensions, as they’ll disappear from the Chrome store. Might mean maintaining a separate store. The authors might not care enough to maintain a Brave version of their extensions.

All in all it’s not great path forward for Brave. At best they’ll have an increased maintenance burden. At worst it gives Google the power to force them to drop Manifest v2 or be overwhelmed by maintenance. But this is what we get for handing an effective monopoly to Google.

Switch to Firefox!