Can the server access the client directly?

Question

I have a small requirement in PHP as shown below. Some things like chat.

For example, there are 2 users A and B.

When "A" clicks on the "Chat" link. "B" should automatically get one javascript popup.

Is there any way to do this other than the following. - One JS script runs continuously with AJAX. I do not want to constantly interact with the client server.

Is there any way to directly send the browser status to the browser?

Thanks in advance.

Answer 1

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Answer 2

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Answer 3

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