How to check that the user is online before sending a push in Chrome?

It is possible to check push api for Chrome that the user is online?
The problem: doing the chat for the site managers on a shift, we need to send a notice only to those managers who are now working, and indeed to know whether there are managers now in the network or not. This is something you can do via push api for Chrome
July 8th 19 at 11:38
1 answer
July 8th 19 at 11:40
I doubt that this is possible using push api
Here is an article about another way

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