A do appreciate that browsers provide a standard way to ask for these permissions. For instance, I deny most of the "know your location" queries, but it is not

A do appreciate that browsers provide a standard way to ask for these permissions. For instance, I deny most of the "know your location" queries, but it is not infrequent that I do wish to use a Web service that asks to know where I am. Pop-up is a bad way, the above proposal for (admittedly some more clutter) buttons in address bar is better.