const es = new EventSource("https://localhost/sse");

es.onopen = e => console.log("EventSource open");

es.addEventListener("message", e => console.log(e.data));

// Event listener for custom event
es.addEventListener( "join", e => console.log(`${e.data} joined`))

https://github.com/tyrion/sse-websockets-demo

via https://sebsauvage.net/links/?CEiR6w
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