A proxy can do very little to actually block ads compared to what a web browser can do. Web browser _is_ the right place, or at least it is the only place where

A proxy can do very little to actually block ads compared to what a web browser can do. Web browser _is_ the right place, or at least it is the only place where you can actually do something intelligent to block ads. For example, if you are blocking ads at a proxy, it is trivial for site owners to detect it and then your filtering proxy can literally do nothing to compensate. A huge chunk of all the filters in adblocking lists are basically to defeat anti-adblocking functionality...