There are several nuances:
Chrome for Android . Push messages will run Service Worker and the web application, even if the browser is closed. This is a standard and ideal position on all platforms.
Desktop Chrome . Press Push and wake up the worker if the browser is still open. However, it will not work if the browser is closed. You can force the browser to stay open if you have the Chrome app installed, which runs in the background. In addition, we (the Chrome team) are developing how we enable this by default on Windows, Mac, and Linux.
Chrome for iOS : Push just doesn't work on this platform
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