The Notifications API allows web pages to control the display of system notifications to the end user — these are outside the top-level browsing context viewport, so therefore can be displayed even the user has switched tabs or moved to a different app. The API is designed to be compatible with existing notification systems across different platforms.
The onerror property of the Notification interface specifies an event listener to receive error events. These events occur when something goes wrong with a Notification (in many cases an error preventing the notification from being displayed.)
The renotify read-only property of the Notification interface specifies whether the user should be notified after a new notification replaces an old one, as specified in the renotify option of the Notification() constructor.
The sticky read-only property of the Notification interface specifies whether the notification should be 'sticky' or not. When we say a notification is sticky, it means that notification is not easily clearable by the user. This is specified in the sticky option of the Notification() constructor.