The harm to me is the implementation is terrible - local or not (assuming no AI based telemetry). If their answer is AI then it pretty much means they won't make a non-AI solution. Today I just got my first stupid AI tab grouping in Firefox that makes zero intuitive sense. I just want grouping not from an AI reading my tabs. It should just be based on where my tabs were opened from. I also tried Waterfox today because of this post and while I'd prefer horizontal grouping atleast their implementation isn't stupid. Language translation is a opaque complex process. Tabs being grouped from other tabs is not good when opaque and unpredictable and does not need AI.