Reported here by Hari krishna:
https://groups.google.com/a/chromium.org/d/msg/chromium-dev/XohqW3mcMME/WvEHucgSCgAJ
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We have been playing around serviceWorker functionalities. What we did is, we created a message event handler, that spawns another message event for every minute.

Example code shown below.
self.addEventListener('message', function (event) {
    var spawnNewMessageEvent = function (data) {
        return new Promise(function (success) {
            setTimeout(function () {
                var sw = self.registration.active;
                sw.postMessage(data);
                success("success");
            }, 30000)
        });
    };
    event.waitUntil(doSomething().then(spawnNewMessageEvent));
});