[jeffrogers]

Are the QUIC HTTP/3 Connection Migration IDs an end run around limitations with cookies, ad blockers, MAC spoofing, and other forms of anti-tracking measures? My understanding is that these IDs survive network switching, sessions, etc.

[Matthias247]

QUIC connection IDs are transport level IDs, and are valid for as long as the connection is established. They will survive network path switches (by design to enable migration), but e.g. are not related any sessions on application level.

QUIC connection IDs can also change while the connection is active, so there no 1:1 relation between connection ID and connection either.