Yeah, we had been doing that initially and found that there are lots of imaginative ways to use e.g. refresh meta-tags that browsers do accept but we did not (e

Yeah, we had been doing that initially and found that there are lots of imaginative ways to use e.g. refresh meta-tags that browsers do accept but we did not (e.g. somebody might say content="0.0; url=https://example.com/"* https://example.com/"*) and more and more networks and agencies switching to JS-based redirects lead to a headless browser being easier in the end, despite dealing with these specific issues. A simple self.location.href = ...* is still doable (-ish, because I've seen conditional changes that were essentially if(false)... to disable a redirect, which we obviously didn't consider when pattern matching), but once they include e.g. jQuery (and some do on a simple redirect page) it got far too complicated.