Is this actually exploitable with the current set of browsers?<p>Looking at the documentation of the API [<a href="https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerRegistration/periodicSync" rel="nofollow">https://developer.mozilla.org/en-US/docs/Web/API/ServiceWork...</a>]<p>and it says in a yellow note at the top of the docs
This feature was mentioned as an idea in the SW explainer at some point, but as yet has not been implemented anywhere.<p>My guess is that is only an experimental feature currently