I haven't tried Brave, never understood the point of it. What does Brave + uBlock offer you that Firefox + uBlock doesn't?

I hope you mean uBlock Origin.

Brave and uBO share filter tech and we aim to make uBO unnecessary (this may require setting shields to aggressive). We do much more than any extension can do, and Google has made it clear they will further restrict extension APIs.

https://www.theregister.com/2019/05/29/google_webrequest_api...

https://brave.com/privacy-updates-7/ (latest in series)

What does Google restricting APIs in Chrome have to do with Firefox? I haven't heard of any plans like that from them.

Firefox has had same API as Chrome for a while.