[dingaling]

> Excluding leaks, the ISP does not see the hostnames

Unfortunately they can, either through the unencrypted hostname passed in SNI or in the cert returned by the server .

[codedokode]

In TLS 1.3 server certs are encrypted. And while browsers support ECH (Encrypted Client Hello) to encrypt SNI, almost no server supports it. Cloudflare has ECH disabled globally for some "issues" they do not disclose [1].

[1] https://developers.cloudflare.com/ssl/edge-certificates/ech/