Detect if a PWA is Visible with the Page Visibility API

Need to figure out when your PWA comes to the foreground? The modern web has you covered with the Page Visibility API.

document.addEventListener("visibilitychange", () => {
  const state = document.visibilityState;
  if (state === "hidden") {
    // your PWA is now in the background
  }

  if (state === "visible") {
    // your PWA is now in the foreground
    refreshData();
  }
});

Note: this API isn't specific to PWAs, it works for non-PWA websites/webapps as well.

Most documentation talks about how this event fires when switching tabs, but this also fires when a PWA is foregrounded/backgrounded.

Try it out yourself by going to https://visibility-api.netlify.app/ and adding it to your home screen.