[reconnecting]

I thought you wanted users to flag Cloudflare domains through a browser extension, which is why I got confused.

[Groxx]

I want to visibly indicate it on links / visits, for myself, so I can learn what the impact is and what might be worth avoiding. And how tightly bound use of it is - often these kinds of services are used/avoided by pockets that are somewhat closed (spam networks, indie webrings, etc), and I'd like to get a feel for where those pockets might be.

I assume there's some way to detect that mechanically, which is probably what you described. I just haven't yet seen anything that does this - hopefully it already exists, if not I should probably make it.

[reconnecting]

There are domain zone files, and they sometimes contain NS records. Cloudflare hosted domains are easy to identify via their NS records, which also makes Cloudflare customers an ideal target for phishing.

[Groxx]

(replying for myself, and for anyone else interested)

Actually I think this might not be too hard. Cloudflare has a relatively small, published list of IP addresses: https://www.cloudflare.com/ips/ and Firefox has a DNS API for extensions: https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/Web... (and kinda mostly not chrome, dev channel only: https://developer.chrome.com/docs/extensions/reference/api/d... )

That's not too hard to plug together, and Firefox even has stuff like `["offline"]` so you can avoid sending any requests at all.

[Groxx]

Neat: https://postimg.cc/dLmzHfhJ

So yea, that strategy seems to work. PoC functional, gonna clean it up later.