https://www.partykit.io/ sort of? maybe?

For disappearing messages to work, your conversation partner has to promise they won’t take photos of their screen, and they have to promise to use an app that actually implements the feature instead of just pretending to, and the app developers have to promise to have implemented the code to delete a message when the service says it should

Is there actually a cryptographically-sound and physically-complete method for ensuring that a message is only legible for a temporary duration once it leaves your own device and is delivered to someone elses?

Hmmm, is CloudFlare known for being a bad actor in terms of privacy?

Setting that aside, no matter what you pick, you’ll be exposing your IP address, from which your ISP and/or general location may be derived

If you don’t trust CloudFlare with that information then you basically cannot trust anyone else, so maybe you’d need to run your own service and ping that instead now that you’re in a situation where you can only trust yourself 🤷

The other issue that comes to mind is that you’re only testing reachability to one address, which means you could get a false negative where that address stops working but the rest of the internet is actually fine