Ad blocking extensions are really a "last defense" and can be slowly lobotomised as they are under browser vendors' control.
HOSTS files may also be simplest (I totally disagree btw), but I can't imagine they're anywhere near the most common.
That's exactly how DoH is being implemented, and it's why it has caused so much controversy.
That is correct, the IPv6 probes are embedded in the Chromium source, and are removed by the Ungoogled Chromium and/or Inox patchset [1].
[1] https://github.com/Eloston/ungoogled-chromium/tree/master/pa...
That's also a major difference to Ungoogled Chromium, where UC will request "https://..." by default if you just enter the domain.
So in the case of Enterprise Proxies that have no locally force-installed cert to sniff on internet traffic will likely end up with HTTP-everywhere being used. But usually employers that encourage such bad practices also install their snakeoil MITM certificates locally.
You might be thinking of the HTTP server push functionality. That was introduced with HTTP/2 and has been deployed for years already over TCP transports (i.e. totally unrelated to QUIC).
Due to how advertising networks work, I'd be surprised if anyone used server push in the way you fear.
there is such a poisonous mentality that has taken root, that is popular. no one at the ietf shares these delusional fears, & it's not because the ietf is a bought out shadow puppet. it's because in reality http3 brings what http2 brought but technically better which brought what http1 brought but technically better.
Did you have a good look at how the internet evolved in the last 15 years?
The IETF can invent HTTP/23 with DNS-over-whatever tomorrow, that doesn't change anything about the general state of the internet, which can best be summarized as a "burning pile of poop".
Do you really need any examples of how broken everything is? Do you really wonder that people have "grimdark fantasies" about what the "next cool web feature" will bring to us?