The graphene community in the past has pointed out Firefox’s incomplete content sandboxing implementation and suggested that other aspects of security are not up to chromiums standard. They pointed out other technical shortcomings as well, though I can’t recall them, I’m not sure how urgent they’d be.

This was several years ago, and I’m not sure if any of this has been addressed, but I don’t think I wouldn’t like to rely on manifest v3 compliant ad blocking.

I get the impression that Firefox may continue to lag in this regard. I don’t feel that people like us are made vulnerable by this, though I do worry a little bit about people like my parents.