Yeah, that seems to be the case (confirmed with their little example at https://github.com/mdn/dom-examples/tree/master/server-sent-events https://github.com/md

Yeah, that seems to be the case (confirmed with their little example at https://github.com/mdn/dom-examples/tree/master/server-sent-events https://github.com/mdn/dom-examples/tree/master/server-sent-...). Once the connection is closed you can see things, but that's not particularly useful for debugging!