The WakeLock interface of the Screen Wake Lock API prevents device screens from dimming or locking when an application needs to keep running.

The system wake lock is exposed through the global Navigator.wakeLock property.

request()

Requests a WakeLockSentinel object, which returns a Promise that resolves with a WakeLockSentinel object.

The following asynchronous function requests a WakeLockSentinel object. The WakeLock.request() method is wrapped in a try...catch statement to account for if the browser refuses the request for any reason.

try {
  const wakeLock = await navigator.wakeLock.request("screen");
} catch (err) {
  // the wake lock request fails - usually system related, such being low on battery
  console.log(`${err.name}, ${err.message}`);
}