testing serviceworker fetch handler

you can visit this page again if

• you don't use chrome browser,
• you don't block third-party xmlhttprequests,
• you block javascript, or
• you type the url in the address bar.

in other words, you can't come here again via links from other domains if you block third-party xmlhttprequests using a chrome extension. that applies both webrequest and declarative net request.

this page installs a serviceworker with a simple fetch handler, which just fetches and returns as is (fetch(request).then(response=>response)). it shouldn't be a problem because the script file is in the same directory as this html, and it never modifies requests or responses.

when you come here next time, the serviceworker will have already been in your browser. and it will try to fetch this page (with a mysterious mode). i think it's a little weird, but i don't think it's a bug. what i think is a bug is what will happen next. chrome will report to its extensions that the initiator of the request is the referrer. i.e. if you come here via google.com, chrome will say something like, "hey uBlock origin, google is fetching this page. do you let the request go?" of course the code is not from one of the biggest companies in the world but from this tiny html page. so i filed a crbug.