Service workers can be used to build a small chat message feature into your browser. This recipe demonstrates how to communicate between a page and the service worker by relaying messages between pages we are going to use to build our little chat app.
To get started with service workers, you will need to have the service worker experiment feature turned on in your browser settings. If you have not done this yet, refer to the Setting up service workers recipe of Chapter 1, Learning Service Worker Basics. Service workers only run across HTTPS. To find out how to set up a development environment to support this feature, refer to the Setting up GitHub pages for SSL recipe of Chapter 1, Learning Service Worker Basics.