Service workers install themselves. If you install enough of them, could all these background processes grind the browser to a halt? Anthony Lindsay, Dublin AG: There are currently three background tasks run via service workers: push notifications, background syncs and periodic syncs. And each requires explicit user permission before it becomes available. Push notification delivery is controlled by the server, so spamming our users does run the risk of tying up their browser processes, running down their battery and depleting their mobile data allocations. Don’t do it. Background sync attempts to do something (eg send a message) once a network connection is available, so it should not be an issue. Also, periodic sync is being designed to avoid creating issues for our users, enabling us to set a minimum duration between synchronisation requests, limit its effect on the battery and avoid using cellular data.