Can Web Push Notifications not also be considered as an alternative?
They are quite different from SSE and WebSockets in some aspects. Using Web Workers for some core feature shouldn't be considered lightly. But the end result is pub/sub, so it's worth to check out.
Technically it would fit nicely. Unfortunately, it requires the user to explicitly give permissions to show notifications to the website, even if you don't show any notifications. This is a blocker for its usage in many cases.
I think you probably mean web Notification. Although it is always use with Web Push. And also it is generally rate-limited due to its default usage (display a message to user). On the other side, Websocket and SSE talks to program, there is just no rate limit thing exist.
They are quite different from SSE and WebSockets in some aspects. Using Web Workers for some core feature shouldn't be considered lightly. But the end result is pub/sub, so it's worth to check out.
https://developer.mozilla.org/en-US/docs/Web/API/Push_API/Be...